Light for Cities: Lighting Design for Urban Spaces. A Handbook 9783764382636

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Light for Cities

Ulrike Brandi, Christoph Geissmar-Brandi

Lighting Design for Urban Spaces. A Handbook

Birkhauser - Publishers for Architecture Basel· Boston· Berlin

Contents Foreword New light for urban spaces?

6

Introduction Trip to the city

8

Process Concept Development Players and objectives

25

Survey, analysis and concept

26

Feasibility study and financing

27

Committees and public relations

28

Lighting tests

29

Concept implementation in stages

30

Lighting and design guide

30

Efficiency and Performance Profiles Efficiency of new lighting systems: Prerequisites

32

"Lighting rnasterplan": Performance profile of a lighting designer

35

Implementation From concept to design

38

Production information

38

Standard award of contract: Specification and invitation to tender

40

Alternatives to standard award of contract: Staggered contracts

41

Post installation: Alignment of luminaires and control

43

Standards and recommendations: Possibilities and limitations

45

"Light pollution": Avoidance strategies

46

Lamps and Luminaires The right lamps for exterior lighting: Selection criteria

48

Luminaires, poles and attachment points: Requirements

50

Family of luminaires: Advantages

50

Luminaires as design elements: Prospects and potentials

52

Controlling urban light: Future prospects

53

2 Typology Travelling by Car Main roads and side streets

56

Bridges

59

Roundabouts

60

Traffic signs

63

Multi-storey car parks

64

Car parks

67

Petrol stations

68

Stop and go

71

On Foot Squares

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Footpaths and sidewalks

75

Trees

76

Facades and illuminated advertising

79

Shop windows

80

Underground stations

83

Boulevards

84

Design Principles and Techniques

86

Lighting paths and facades: Design techniques

90

3 Completed Schemes Boulevard: "BUrger" Bremerhaven

94

Historical Facade: Hamburg Town Hall

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Shopping Centre: London - White City

102

Airport: Terminal II, Munich

106

Historical Town: Einbeck

110

Riverside Walk: Jungfernstieg, Hamburg

112

Fountains and Monuments: Schonbrunn, Vienna

116

Park: Negara Bank, Kuala Lumpur

118

Square: Thomaskirchhof, Leipzig

120

Temporary Light Installation: Gasometer, Oberhausen

122

Urban District: Zurich Affoltern

124

Small Town: Lemgo

128

Large City: Bremen

132

Large City: Luxembourg

138

New District: HafenCity Hamburg

142

4 Developments Light and Shadow in the Public Realm: Past and Present

150

Appendix Selective Bibliography

158

Imprint

168

New light for urban spaces? Electric light has, since the beginning ofthe 20th century (in London around 1880) driven back the dark, and considerably changed the meaning ofthe night in our cities. The daytime world was extended into an emerging nightlife that held an inner attraction while being alluringly "dangerous". The illuminated night breathed a new beauty into the cities with a special aura. Now, at the beginning ofthe 21st century, we wonder about the character offuture public light. We need to analyse the existing light at the end ofthe 20th century as part of the process ofdeveloping an appropriate concept. This essentially comprises functional lighting and effect lighting - just as at the beginning of the century. Street lighting and pedestrian lighting are mainly functional in design and produce most public light. For a long time, outdoor lighting systems were designed by continually adding to the existing; new streets and buildings were constructed with more light. Technological progress ofthe networks, as well as luminaires and lamps, has been going on for decades. More or less tightly knit networks of"street lights" have developed over many years, their light now visible from space satellites. And conversely, "light pollution" prevents us from seeing a truly dark sky in many places. Effect lighting and event lighting is generally short-lived. It is most typically found on lit facades, monuments or other "stages" that obviously could, and still can, attract a lot ofpopular attention. The modern term for this type of lighting is light installation, unintentionally describing the temporary and theatrical nature oflight. It is closely related to the illuminated advertising boards that are an integral part ofall large cities. Because we take street lighting at night for granted we tend to forget the extent of the development with light that has taken place in the past 150 years. The function ofinner cities on the one hand, and the sprawl ofcities into the periphery or their conglomeration into regions, on the other hand, has been controversially discussed in recent years - and continues to be a topic of discussion. In Europe, city dwellers are putting a lot of effort into the restoration of their once very attractive centres. The refurbishment oflighting systems and the design ofnew light, mostly taking place in central urban areas, will always play an important part. The various reasons for this will be discussed. There are many prime examples, and a proportionately large number ofattempts to emulate these. An even larger number ofproposals are in the minds of responsible investors, marketing people, advertising groups, public authorities, power suppliers, supply industries and designers, residents and customers in the city. All this can culminate in masterplans for public lighting which, apart from defining general concepts, often put forward designs for specific urban districts. Alternatively, a number ofseparate initiatives for good lighting are formed.

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In the above context, this book serves as an actual guideline for better lighting in urban streets, gardens, squares and buildings. Firstly, the design process leading to new lighting must be discussed. Technical knowledge about lighting systems for external areas and their control is the second aspect. Good solutions for urban lighting require a creative imagination in order to rethink the mediocre and commonplace look oflight in the daytime and at night. At first it seems banal. But it is precisely the everyday occurrence ofartificial light that requires a small phenomenology with practical examples, and so the third field. Our fourth approach attempts to enhance further the wealth ofideas. How to set out on a new lighting design task is described as a narrative; our progress into the city entering an every-increasing density. The bird's eye view from the plane interchanges with the perspective of the pedestrian. A good design is not possible without looking in particular at the historical perspectives ofurban lighting, and at artificial light in a cultural context; we briefly touch on this subject. The appendix will entice the reader to delve deeper into the subject matter. Ulrike Brandi Christoph Geissmar-Brandi September 2006

Introduction : Tr ip to the city

8

It is only with the benefit of light, after all, that urban spaces become accessible at night. The symbiosis of light and its surroundings plays an essential role in architecture, as well as in landscape design and urban planning. In order to accurately connect different light situations with where they occur in urban spaces, we will follow a fictional lighting designer who, after having arrived on an airplane in the evening, drives into a city centre in the dark. This thought model or design scenario is not related to any specific European city, but is broadly transferable - in search of local equivalents.

9 lntrcd uction: Trip to the City

From the plane the passenger observes the city's sea oflights. He catches a glimpse ofthe structure of the city passing from a bird's eye perspective: a river around which the dense centre huddles, the transversals, sports fields and petrol stations bright as daylight, dark parks and industrial areas. The traveller sees the existing lights in the city laid out beneath him, in the configuration ofa lighting masterplan. He recognises the light gradations and local light hierarchies ofthe city he is now approaching.

10

Maybe he will see the runway identification lights close to the ground before the plane reaches the apron, an extreme version ofthe relationship oflightspace.

11

Introduction: Trip to the City

The apron is a space that bears no reference; essentially it is an area that is lit uniformly and glare-free, from extremely high masts. The light on the airport apron is almost more "mechanical" than the floodlight ofa stadium, bright and colour television-compatible - a special public place. The apron is public too, but people do not walk on it, it is only meant for rolling and manoeuvring. Ifhe does not have to board a bus to get to the terminal building, he enters into a "finger", a loveless metal shell that takes him to the gate. This is true ofall airports and it is surprising that such design flaws have not yet been addressed by anyone.

12

Escalators and moving walkways are always found in these passages. They are generally brightly lit with light close to the ground, most typically with fluorescent lamps. Recessed lights in the steps provide glare-free light and attract the attention of those moving up or down the stairs; often the light is reflected or refracted in the hard glass ofthe handrail.

13 lr-troduction: Trip to the City

The interior spaces ofairports have a hybrid character in terms oflighting. The habitually monotonous illumination ofits long corridors abruptly changes into complex displays oflight technology as soon as the passenger reaches the shops or enters the prestigious terminal area where the airlines present themselves. So immediately on leaving the plane there is a marked contrast between the well-tended ambience ofthe cabin and the subsequent space.

14

After his passage through the airport, our fictional lighting designer proceeds to his hire car in the car park. The car park is similar to the connecting pier between airplane and imposing airport building. Often only a door and several steps connect high-quality interiors and the unimaginative car parks. These are generally diffusely and inadequately lit. The next space he encounters is the interior ofthe car, greeting him with a whole array oflight gimmicks that fail, however, to produce a pleasant light atmosphere. Car interiors, including the usage of daylight, are the dinosaurs oflighting technology.

15 Introduction: Trip to the City

On leaving the car park, the headlights ofhis car produce a bright, clearly defined field ofvision on the tarmac, offering a certain sense ofsecurity within the immediate vicinity ofthe car.

16

The road leading into a city is generally lit across several lanes with bright and uniform sodium-vapour lamps at a height ofapproximately twelve metressufficient for driving. Urban sprawl extends along the roadside, with lone light points or illuminated advertising panels placing single accents. After a while suburbia begins. Here too, yellow-orange sodium-vapour lamps light the side streets. But the mounting heights are lower; street illumination is irregular.

17 Introduction: Trip to the City

Diversity is now added to the lighting of the road, still wide at this point: the mounting heights ofthe street lights are further reduced whilst the white fluorescent light emitted from the old lighting system presumably gives out the necessar y brightness. Traffic lights with their colours now enter the picture; and there are signals too . Footpaths lit from a height offour metres are supplemented by shop windows.

18

Some areas are lit disparately, such as pedestrian crossings, bus and tram stops and underground stations. In addition to this, illuminated and backlit signage appears. Generally, everything seems to be much brighter, but also more diffuse.

19

Introduction: Trip to the City

The car journey ends on driving into the concealed entrance to an underground car park ofa central business hotel. After checking into the hotel, a stroll through the city centre seems appropriate. The approach to the brightly lit Town Hall Square is via a narrow and dark side street. Such encounters with the urban squares ofParis were likened to entering a ballroom 130 years ago. The facade of the Town Hall is lit from two masts and from the rooftops opposite. Not many people are about in the square, although it is early evening. The traveller wants to visit a restaurant in one of the nearby shopping streets - and all on foot.

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After striving to get his bearings, he passes a brightly lit pedestrian zone. All the shops are closed, but their windows shine out. The zone is amply furnished with signs and bollards, and advertising panels on the facades reach up to the eaves. The lighting is not graspable - an unsatisfactory situation.

21 Introduction, Trip to the City

The traveller occupies a room at the top ofthe hotel. He no longer has an aerial view of a sea oflights - but rather looks at the light horizon ofthe city. Does it still have anything to offer?

22

The fictional journey into the city could have ended differently. However, it identifies the essentials of the model, placing urban light in a special relationship to the protagonist and the spaces surrounding him. Spaces through which everyone must pass; urban space is defined by an enduring rite of passage: in this fictional journey the traveller changes from car to aeroplane, from train to public transport, and finally he walks. The fictional journey to the city is a model for readers and designers. The model attempts to relate the changing environs of the traveller through the eyes of a lighting designer. For this trip, everyday experiences have been condensed into a comprehensible, short journey through the city's light structures.

23 Introduction, Trip to the City

Proc

Concept Development Players and objectives

The terms lighting masterplan, urban lighting concept and plan lumiere were newly coined in recent years in discussions about the future of (inner) cities; today, as the practical planning processes] evolve, so do the definitions of these terms. The players are urban planning departments, civil engineering departments, public utility companies and lighting designers whose projects are cities and urban sites ofdifferent sizes, as well as exhibition spaces and leisure parks. There is no preset course of action, as that defined by the Official Scale of Fees for Services by Architects and Engineers (Honorarordnung fur Architekten und Ingenieure HOAI) for the planning and construction ofbuildings, and so the parties involved must work out their own joint strategy. The initiative in these instances is usually taken by urban planning departments or entrepreneurs, often in response to pre-existing pressures: the public space has been criticised Integrated lighting concepts that take street lighting and building illumination into consideration strengthen the atmosphere of a city.

as being unattractive and "people are staying away". By the time the involved parties choose to employ "light" as a design element, they have already reached a number ofbasic insights, which will then lead to the commissioning ofa lighting masterplan or individual lighting projects. - New lighting on streets and squares creates visual impact and is therefore a promising course ofaction. - Existing systems are out of date or at the end of their economic life and need to be replaced. - Compared to other engineering and infrastructural projects such as the redevelopment ofstreets and squares, lighting improvements are among the most cost-efficient and sustainable measures. The probability of realising these improvements is therefore comparatively high and the long-term investments are profitable within a relatively short time span. Savings are gained by low power consumption and shorter maintenance intervals for the replacement oflamps. - Working with a comparatively large number of consultants, who often have diverging interests, requires extensive coordination and management. If proposals for positioning poles and overhead wiring include locations on private property, they must be submitted for permission. The "tastes" ofindividual business owners are diverse. A consistent design can therefore only be realised if consensus is reached with regard to integration into a specific scheme. Just one person not willing to cooperate can seriously upset the design process. On the other hand, consensus can bring swift improvements to the appearance of a street at night and have a positive effect on business. 1 Recommended as a primer on the topic, chiefly In relation to Europe: Klaus Selle (Ed.). Was ist los mit den offentl.chen Raumen? Analysen, Positioren. Konzepte, second edition, Aachen, Dortmund, Hanover 2003, distributed by Dortmunder Vertrieb fur Bauund Planungsilteratur

25

Survey, analysis and concept Once the desire for change has been acknowledged, the search for a sustainable concept can commence. A lighting designer, who has the relevant experience and is able to show design examples from other cities, could spark offinitial thoughts and ideas and be invited to give a lecture. The information contained in the lecture may provide the material for identifying sites from which the brieffor a concept can be formulated.

1)

Concept stage: The circle ofdecision makers should be limited to the initiators, or better still, their representatives. Experience has shown that it is difficult to achieve results if too many people are involved in the decision-making process at the concept stage. One reason is the broad range of expectations associated with "different" light. It is difficult to theoretically "consider" light in advance and also to imagine its effect. Once a sustainable concept has been devised, it is

Aerial view of Marktplatz Leipzig, The lighting concept embraces surrounding areas.

usually persuasive enough to reach the required consensus in favour ofredevelopment. The concept stage is the best time to determine who should be the short-term or permanent client of the job and be in charge ofco-ordination, independent ofthe available funds at this point. + 2) Commissioning the concept: The procedure for appointing a consultant depends on the client's regulations. Public agencies can circumvent the constraints ofbudgets and public procurement laws and obtain greater freedom in the commissioning of contracts; private clients can generally formulate their own competition terms. In addition, there are standard competitions conducted according to professionallaws for architects and landscape architects. These consultants will then join forces with lighting designers to form competition teams. This option will inevitably broaden the scope ofthe task, diminishing the advantages ofa complete focus on "new light': On the other hand, such collaborations do make an integrated approach possible in the first place. To achieve good results, the design ofa concept should be by external appointment, since the know-how ofexperts at local authorities or operating companies is generally required to focus on existing situations and ongoing operations. Innovation, the ''big hit", must come from "outside", possibly from another city or a different country. However, there are few lighting design practices that are able to handle the design - in terms ofquality, precision and long-term perspectives - oflarge, expansive open spaces or entire city centres. Such design tasks require many years of experience and versatile practical skills. Since this is not part of

26

professional training programmes, consultants possessing the necessary expertise are rare. 3) Fee:

The fee for a masterplan is negotiable, as the existing fee scales do not cover the relevant performance profile. Time and good local knowledge are required for the compilation ofa convincing masterplan. It is not therefore advisable to radically reduce the consultants' input. Commissioning the work in stages is recommended. One of the advantages of a lighting masterplan is that it deals with only one "trade" in isolation and can therefore utilise and fully exploit all effects and potentials of the light medium.

Feasibility studies and financing The alignment of the undergroun d statio n beneath the market and the histori cal diamond-shaped paving pattern in the square deter mine the location of the tall li ghtin g masts.

Once a concept has been formulated, it is advisable to conduct a feasibility study.All facets of realisation are examined, and the study will then set out to describe and evaluate the details that would follow after the project has been implemented. A feasibility study is thus an ideal instrument for raising the necessary funds. It may state the relevant criteria for public subsidies, contain actual commitment of budget funds or help private investors to find appropriate commercial real estate and open space. A study on new lighting for public spaces will analyse the impact on neighbouring buildings, engineering structures, traffic and, finally, on the open space. It will compare the existing situation with future scenarios (possibly planned in several construction phases) and evaluate the advantages and disadvantages of

,, ,

the proposal. The description of the existing situation will include the past use

,

of the site .This is generally found below ground: the many existing service runs (electricity, gas, water, telephone and other services), inspection chambers, subsoil conditions, alongside the question oflong-established property and ownership rights must be considered. The study will also address compliance with rules, standards, orders, regulations and by-laws. In an interdisciplinary and comprehensive manner, each ofthe appointed consultants will illustrate the impact of the proposed light on every specific area, taking individual interests into consideration. Neighbouring buildings may be shown in a new light. Bridges, access and egress to underground stations may require new "light connections".Traffic flow for cars, bicycles and pedestrians may be aligned along entirely new routes, if the budget will allow for it - and thus require different light. Finally, the feasibility study must address the chang es proposed for streets and squares, planting, proposed materials, a change in colour and street furn iture, and how these affect the new lighting 27 Process: Concept Development

Neumarkt Dresden: The Frauenkirche is free-standir g in the square; traditional low lighting poles blend in with the surrounding facades.

scheme. Details ofwhat exactly needs to be included in the study depend on the specific site, just like the entire planning process. Currently, a number ofnew build-operate-transfer (BOT) models are being developed, aimed at competition in the power supply market. Since public lighting uses a constant amount ofpower during the night, when utilisation of power stations is low, it is attractive for power suppliers to enter into this competition. Such long-term contracts guarantee continuous and constant utilisation, with easily forecasted and contractually fixed values.

Committees and public relations

Public administration committees and indeed the public itself can only be won over with the triad of "urban lighting concept"- "feasibility study" - "financing". The professionally prepared service proposal turns into a political issue. It is now up to the confident clients to act. To what extent quick results and implementation are achieved varies from case to case, depending on individuals and political constellations, and the question ofservices previously rendered. Consultants can lend support and promote their concepts. The process may be time-consuming - as will the process ofthe subsequent lighting tests - and may lead to "repetition" in mediation efforts.

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Lighting tests

Lighting tests are very time-consuming procedures intended to demonstrate the desired effects ofa lighting scheme. However, unlike computer simulations and other costly methods, they have proven their worth and are an indispensable professional tool. These tests complement the feasibility study with a practical demonstration of a pilot project, during the detailed design stage for the execution or later. They are therefore not part of the design stage. On-site lighting tests sharpen the awareness of the parties involved; they not only demonstrate the desired light effect, but also show the urban space in the dark with the existing lights. During a lighting test, committee members frequently comment that they had never before noticed certain aspect of their cities - including especially attractive ones. It is interesting to examine light situations from a distance and from up close, to

explore the boundaries oftechnical feasibility and to select the optimum solution. Manufacturers ofluminaires - who provide the samples - and technicians or installation firms are involved at this stage. They position the luminaires to be tested and put them into operation. The sampling process provides an opportunity to establish first contacts with potential firms that may be invited to work on the project; these contacts often prove to be extremely informative as there are many regional differences throughout Europe. Lighting tests must be budgeted separately. Suppliers receive payment, the consultants a fee. Their work, which frequently requires extensive input, can only be planned at short notice.

Marktplatz Leipzig: Lighting tests for a lighting pole prototype in a blizzard

29 Process: Concept Development

The cost ofexterior luminaires, including poles and installation, is between 4000- 6 000 euro, sometimes even more. This is tenfold the costs ofinterior lighting, calculated per luminaire. Although exterior luminaires are generally intended to "stay for good", the effort expended for transportation, installation and aligning them is comparatively high, given the fact that this is merely a non-binding sampling scenario.

Concept implementation in stages

Investment costs for large-scale new lighting systems are generally too high to be implemented in the short-term. Hence, it makes sense to plan their implementation in stages, and to take the life cycles of existing lighting systems into consideration. It remains a time-consuming endeavour which cannot be achieved in a day. Depending on the project brief, and subject to budgets and available finances , it is not uncommon that the time-span for implementation ofa masterplan ranges from five to ten years. Naturally, it is easier to obtain a consensus among the parties involved for a smaller, more clearly defined urban site . Projects that extend over such lengthy periods of time require clients who possess sufficient determination and will to follow the job through to implementation. Independent consultants cannot influence future decisions. Hence, the success oflighting masterplans strongly depends on the continuity and perseverance of the parties involved.

Lighting and design guide

The lighting masterplan summarises and illustrates the overall lighting concept for a city. It provides structure and exemplifies the intentions of the lighting designer in a series of drawings and diagrams. It establishes classifications, sets up rules and allocates space for the light image ofthe city. A "lighting and design guide" is a powerful tool that can be used in conjunction with the masterplan. While such a guide does not furnish a plan description in the traditional sense, it does formulate clear rules for the implementation of the plan and for the correct use of the existing ambient lighting in the future. At present, few cities have such lighting and design guides; some do regulate the lighting for advertising panels, and others draw on the regulations for building conservation. The finished plans are only available to a select group ofpeople and read by even fewer. The prerequisites for the plan frequently undergo changes over the course of time. Drafting a clear, concise text composed in the style ofstatutes is

30

therefore a useful measure and also helps municipal authorities to implement the formulated goals. To facilitate the success oflong-term design concepts, overarching "guidelines" may be formulated for large projects. These are drawn up at an early stage and supersede the masterplan conceived by the specialist consultants. The objective oflighting and design guides is to commit individual specialist consultants to a set of overriding rules in order to achieve an homogeneous overall appearance. A masterplan, and for larger projects a lighting and design guide, which is binding to all specialist consultants should be an integral part of the contracts.

The lighting concept for the City of Hamburg shows important buildings and squares as well as the ramparts.

31 Process: Concept Development

Efficiency and Performance Profiles Efficiency of new lighting systems: Prerequisites

New lighting systems may become profitable within a short period of time. The initial job costing can be split into investment costs and operating costs . 1) Investments: What needs to be bought?

For a system that is designed for a lifespan of15-20years, sometimes 30 years, the investor or the city or the municipality requires: - a lighting scheme, new luminaires, including lamp s and pole s, their supply, fitting and putting into operation. Presumably the city or municipality has high operating costs it wants to avoid . Hence : 2) Operating costs: How can they be reduced or kept low?

To achieve this, the city needs to obtain good offers for the supply of power and for operation and maintenance or for both from one source (facility management by the power company).

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Lamps (euro) Luminaires (euro) Total installation costs (euro) Operating costs tor 6 years (euro) Burn time/day. w inter. 4 months (hours ) Burn lime/ day. summer. B months (hours) Average burn time (annual hour s) Lamp life approx. (hours) Power absorpti on incl. ballast {kW} Lamp replacement interv als (years) Eleclr icity costs 1st year reuro) Lamp replacement costs (euro) Electr icity costs 2nd year (euro) Lamp replacement costs (euro) Electr icity costs 3rd year (euro) Lamp replacement costs (euro) Electrici ty costs 4th year (euro) Lamp replacement costs (euro) Elect ricity costs 51h year (eur o) Lamp replacement costs (euro) Electr icity costs 6th year (euro) Lamp replacemen t costs (euro ) Total electricity costs for 6 years (euro) Total lamp replacement costs for 6 years (euro)

Average total annual costs (euro )

32

Total annual costs

Operating costs for new systems may be much lower. This is due to : - longer intervals between the replacement oflamps, and the resultant - longer maintenance intervals, - substantially reduced power consumption through efficient lamps. A significant cost reduction would be generated by longer maintenance intervals, immediately reflected in lower annual operating costs. In addition to the reduced operating costs, the city as investor, acting either in the private or in the public sector, would benefit from: - excellent, contemporary lighting in the public realm, - which improves the appeal ofareas slated for redevelopment, - and thus creates a better environment for living and for conducting busi ness . Anticipated costs can be estimated on the basis of the above information. The operating costs ofthe existing system will be known to the present operating company; those of the new system are easy to compute. The consultants will submit estimates for the necessary investment and operating costs. These are based on experience values that appl y to areas or street networks. More complex is the comparison between different lighting systems because their performance will vary. The generally accepted method (see above) is to put a figure on the quantity oflightutilised (lumen in lighting hours) and offset it against the cost. This does no t reflect benefits derived from light quality and indirect positive effects, but at least one is equipped with some quantifiable information. It is also worthwhile to obtain advice on alternative financing models, espe cially from pos sible prospective power suppliers. These companies benefit from a number ofadvantages. They generally accrue substantial reserves and have liquidity. It is in their interest to deliver a constant quantity of power over a long period of time, making plant utilisation easily calculable and enabling them to offer competitive prices on the open market. Consequently, power companies can m ake long-term investments into their own local markets and thus secur e a definite sale. One ofthe difficulties for cities and municipalities is that public urban lighting is not paramount for power companies within the context of the total power demand. Also plants work below capacity at night and thus are expensive. It is a political issue whether national and cheaper suppliers should better utilise their available capacities, or whether local suppliers should make the most of their expensive night hours. Accurate financing options can only be calculated for specific projects.

33 Process: Efficiency and Per form ance Profiles

This plans shows the existing luminaires in different colours in the City of Hanover in 2001.

34

"Lighting masterplan": Performance profile of a lighting designer There is no generally binding performance profile. The first stage ofthe performance profile should comprise the design of a lighting concept, the second stage a description ofservices during implementation. Here is a possible performance profile for the first stage:

1)

Transposing the lighting concept onto a lighting masterplan. Requirements: - The lighting masterplan describes the lighting concept for the site. - The lighting masterplan sets guidelines for the illumination ofa city, it identifies local features and links light themes. Apart from design proposals, the lighting masterplan will also include information on technical and economic aspects.

2)

Design services and deliverables of the lighting masterplan: - Site survey: the survey ofthe existing light situation is conducted with the help ofthe statutory authorities. It forms the basis ofall subsequent design work. Preliminary time schedules and first design ideas are formulated. - Design ofthe masterplan: definition ofprinciples for the different spaces (function and scale) ofroads, squares and facades in order to develop a homogenous scheme, also suitable for incremental implementation. A good working knowledge ofthe site is essential and helps in the identification ofits special features. - The greater the detail ofthe guiding principles - incorporating aspects such as light colour, illuminance, etc. - the more unified the final overall scheme will be. Matters ofsafety, efficiency, sustainability and future-oriented technology should also be considered - Lighting design guide for the masterplan: the lighting design guide establishes the rules for the site. It contains precise descriptions ofthe proposals for the site areas, including all necessary information (lamps, luminaires, etc.). Close collaboration with the city and other consultants is of utmost importance during this stage.

The performance profile for the proposals of the second stage follows on from that of the fist stage: 1) Design and coordination of lighting proposals of the masterplan:

Finalising the proposals: illustrating the lighting design guide with CAD drawings, precise specification ofluminaires and lamps, compiling quantities and costs. Generally this step relates to specific site areas because 35 Process, Efficiency and Performance Profiles

implementation will be incremental, possibly extending over several years. - Lighting test: lighting tests are a trial run ofthe lighting design in a specific part ofthe site. They provide an impression ofthe effect ofthe proposed light on the actual site. It is standard practice to quote for lighting tests for two typical areas. Special services:

- Contributions to publicity work, for example appearance at press conferences, lectures, interviews, - visualisations, - computer models or simulations, - economic efficiency calculations of the proposed systems, - design services for custom-made luminaires. 3) Fees:

- The fees are based on experience values obtained from similar projects ofa comparable size. They are calculated as a lump sum. - Fee proposals also include hourly rates and daily rates. These serve as the basis on which special services are charged, should the client require these (for example repeated presentations, additional lighting tests, etc.). - Services for "design" may be charged according to the Official Scale ofFees for Services by Architects and Engineers (HOAI).

36

Competition entry for the City of Regensburg: The available budget allows for a competition and first pilot projects.

37 Process: Efficiency and Performance Profiles

Implementation From concept to design

The design provides detailed information on the various lighting themes. These may include a hierarchy ofstreets and paths, spatial appearance ofsquares, light falling onto and reflected offfacades, the integration ofparks and the treatment ofoutstanding buildings, as well as the appearance from afar and from up close. Any further course ofaction depends on whether the proposal is for a new system as part ofa new development (such as a leisure park), or whether an existing site is being redeveloped. The fate of the project will be determined (internally) by the degree to which the design intention and detail could be defended at the design stage, and later during implementation, concurrently and interdependently with regard to: - design, composition - cost - technology and finally, at the - initial operation and implementation stage, a step that follows project execution, but is founded in the design. Since lighting design proposals are not self-contained, but tend to continue over longer periods, it may be advantageous for the success of the project if the consultant is retained beyond the point of completion and into the initial operational phase. Implementing the ideas from design, costs and preparation ofproduction information through to the technical aspects and bringing the system into operational use in a detailed and concurrent manner is difficult in practice and success depends on the quality ofthe appointed firms. Still, this is the approach most likely to achieve a successful outcome. The common practice of outsourcing tasks such as project management and cost control frequently results in grave errors. "Project managers" generally lack specific knowledge oflighting design and the related organisational matters often exceed their skills.

Production information

Detailed drawings of exterior lighting specify the precise positions ofluminaires. They state the exact number, the selected luminaire type (often specifying a manufacturer) and the light colour, as well as technical requirements such as control units and ballast. This information is the basis for tendering or ordering products, and includes their subsequent installation.

38

Plans for Whit e City

39 Process: Implementation

Producing these detailed CAD-generated drawings is a complex task because the plans need to be translated into a smaller scale down to the last detail. Possible outlets and mounting positions are an important point of reference during this design stage. Entirely new lighting systems generally require plans drawn from scratch. It is not uncommon, however, to work with existing site plans and to "im provise".

Provided that all parties are in agreement and do not lose sight ofthe technical requirements for the proposed light, this method may also produce good results. Once again , local characteristics, the willingness ofthose involved to communicate and the scope ofthe consultant's commission are critical factors for the quality of the schem e. The subsequ en t sampling plays a vital role in this. Should there be a breakdown in communication, there is a risk that high-quality products and services for which tenders have alread y been issued may be exchanged for supposedly cheaper technology, and that the entire process will come to a halt. The end result would be a poorly executed exterior lighting scheme. This should be avoided on all accounts, especially at this advanced stage in the design process.

Standard award of contract: Specification and invitation to tender

The software that is currently used usually extrapolates the number oflamps, luminaires and technical equipment required for the specifications directly from the detailed drawings. Consequently, every undetected mistake in the detailed drawings entails a later addendum to the specification and thus a possible conflict. Before the specifications are compiled one needs to make sure that all drawings have been approved by all parties, and that everyone has added their binding information to drawings ofthe same issue. The interface between the services provided by consultants such as landscape architects, electrical engineers, lighting designers and project managers, must be precisely defined at this point. Every luminaire, including technical equipment and pole s or mounting, must be described in detail. Manufacturers provide the relevant descriptions which need to be carefully checked by the lighting designer. Drawings and tender documentation must be consistent. The tender documentation, including the specifications, will contain preliminaries describing all tender conditions. These must be counter-signed by the tenderer.

40

The transfer of data to the tenderer (and his submission) takes place via default LN 03

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mence.

Tesis Bodeneinbauleuchte

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digital interfaces. Once the contract has been awarded, construction may com-

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Alternatives to standard award of contract: Staggered contracts

The above-mentioned "standard method" relates to project-specific tenders. If, however, the implementation ofthe masterplan is to take several years, as is the case in many cities, it does not make sense to continually revise the specifications ofthe luminaires selected for the masterplan, or to repeatedly re-specify in conjunction with other urban lighting measures. The plan will comprise a catalogue ofluminaires (commonly preceded by sampling) or at least define luminaire types - a selection of ten to 20 different types ofluminaires is reasonable. Tender negotiations may be held directly with the manufacturers. As with standard tendering, it is advisable to be well prepared. These meetings are timeERCO

consuming because ofthe complex calculations involved and because staggered contracts are generally a challenge to manufacturers. It has become customary - as for the "standard award ofcontract" - to keep the

contract for the supply ofthe luminaires by manufacturers or wholesalers separate from the fitting or installation contract. It may be in the interest ofthe cli75

floodlight

HIT-DE 70W

ent (especially if this is a city) to involve local firms; sometimes the investor hopes for price advantages. One recurring problem is the "gap" on the building site. Luminaire suppliers and installation firms have separate contracts with the client for isolated services, lacking a common goal. The liability for the supply ofluminaires ends at delivery. All problems, such as theft, additional delivery or false information are at the expense ofinstallation or down to the client. As a result, a smooth execution ofworks is a rare occurrence. Itis thus recommended to supply and fit from one source; also to stagger payments prior to completion in line with progress, leaving the final payment until after the

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Data sheets for specific luminaires

41 Process: ImplementatIOn

42

Post installation: Alignment of luminaires and control

Two important tasks remain: the time-consuming alignment ofluminaires (if this could not be carried out as part ofthe installation) and the possible programming ofcontrols. Supervision is part ofthe lighting designer's services, as it is immediately relevant to his design. Both tasks are time-consuming because they have to be carried out at night. Cherry pickers (access platforms) and skilled electricians are needed for the alignment ofspotlights. The programming ofcontrols should be done in consultation with manufacturers' experts, as no control works at first attempt. Since the control system will work throughout the night, it must be tested for the full length ofits operating time and possibly re-tested after a successful trial run. Following this, the system is operational. Now it is up to the client to utilise and publicise it. He holds onto aspirations ofusers enjoying the public space, ofbringing out the poetry of the place and of the operators drawing benefit from the good performance ofthe new technology.

Existing pattern and picturesque situations

Park islands and footpaths in Wallring

Redevelopment and new light arrangements new arrangementof green

mounting height 10 m approx..

park paths. low mounting

colour temperature neutral to

heights. colour temperature

spaces. temporary - possibly

warm white

neutral white

coloured

mounting height 4-7 m approx.. colour temperature warm white

trees in moonlight. colour

lighting design of new

temperature neutral white

squares

facade lighting. colour

transitional zones Wallring

temperature warm white

lighting of edges greenish/bluish

light attractions buildings/squares. temporary - possibly coloured or differentiated white

light accents as orientation points. colour temperature warm white

Masterplan Oldenburg: The masterplan illustrates the overall lighting concept for the city; individual projects may be implemented consecutively.

43 Process: Implementation

Urban situation of the new Mercedes Benz Museum in Stuttgart

44

Standards and recommendations: Possibilities and limitations

It is obvious that lighting systems have always been ofpractical benefit: they

offer orientation and safety in the dark. The illuminance required for lighting a variety ofareas is defined in standards, and is easily calculated. While adhering to these rules is not necessarily a technical problem, they often present a challenge to the aesthetics ofa scheme. Standards are almost exclusively concerned with calculating the levels ofbrightness and the uniform distribution or emission oflight. Standards are quantitative and cannot address qualitative aspects ofexterior lighting; they are merely recommendations. Since standards were primarily developed for road traffic safety, they are largely based on visibility studies for drivers and only rarely on information relating to pedestrians. First and foremost, the objective is to integrate urban lighting of streets, squares and facades into a harmonious whole. For clients and consultants, standards and recommendations only become relevant in cases ofliability disputes. Courts oflaw rule and abide by the current standards of available technology and, in case of doubt, may take the values quoted in the standards as authoritative. As a matter ofprinciple, standards should be considered at the onset ofa proj ect and discussed with the client. They are part of the trade. If the client or the designer should find the standard a "hindrance" to the specific design intent - it would produce the wrong result, for example, or it might not accurately reflect the situation - they can come to a (written) understanding and jointly develop alternative solutions. Some cities deliberately disregard standards to save power and cut costs by reducing lighting points or switching lights off for the night or during parts of the night.

45 Process: Implementation

"Light pollution": Avoidance strategies

The fact that new lighting systems "can do more" than old systems is due to innovations, mainly in lamp technology, and increased knowledge ofthe influence oflight on the immediate surroundings or the environment as a whole. One important objective is to avoid light pollution. Many ofthe old devices are insufficiently glare-reduced and have no reflectors or bad ones. Often their light shines in all directions resulting in "stray light". The most common example is the globe luminaire, extremely popular over a long period of time for its restrained design. But even they shine against the sky. In many regions of the world, bright light fog impedes on the view of the night sky. The International Dark-Sky Association (IDA) was founded in 1988 to promote the protection of the night sky and fight against light pollution. We are all familiar with satellite images ofthe Earth dotted with glowing urban conglomerates. Contemporary light is directional and cut off"towards the top", preventing the loss oflight and of power. High-quality light will also be glare-reduced, to the greatest possible extent. Although anti-glare devices reduce the efficiency ofa luminaire, this is a small price to pay for directional light that is nearly glare-free. Acceptance ofnew systems is almost always compromised by the presence (or the perceived presence) ofglare. Hence, it is important to find the optimal balance between the desired light effect upon surfaces, elevations or objects on the one hand, and acceptable, albeit minimal glare from as few directions as possible on the other hand. This also applies to light immission. It occurs, for example, when private spaces such as front gardens or facades are lit too brightly from public light sources, causing more light to fall into a home. Non-directional light or light causing glare is one ofthe main reasons for the poor quality oflight in our cities today (exacerbated by the longevity ofthe lighting systems). From this perspective, better light is not a question ofideas or temporary installations, but one ofindependent designs combined with the skilled application oftechnical innovations. To appreciate this, we need to recognise that less light is often better than more.

46

Light emission in Europe and the resultant invisibility of the stars

47 Process, Implementa tion

Lamps and Luminaires

The right lamps for exterior lighting: Selection criteria

Lamps form the heart ofa lighting concept. Their technical properties have a marked impact on the light ambience; they emit brilliant or soft light, cold or warm, strongly demarcating or diffusely flowing light. The light they cast has different colour temperatures (warm white up to 3300 degrees Kelvin; neutral white 3300 to 5 000 Kelvin; daylight white above 5 000 Kelvin) and different colour rendition indices (Ra). Lamps also determine the functionality of the entire lighting system: a group offluorescent lights may be switched on instantaneously, whereas the various metal vapour lamps require some time to reach the operating luminous flux, especially on hot re-ignition. Lighting systems are attractive only as long as they work; the economic life of lamps plays a significant role in this. The longer the life, the greater the chance oflamps being replaced at the right time, and the less labour-intensive and costly are maintenance operations. Many German cities are currently trying to extend maintenance intervals for street lighting from two to four years. To a large extent the lamps employed determine the operating efficiency of lighting systems, not just in terms ofinvestment costs (fluorescent lamps cost a fraction ofmetal-vapour lamps), but also in terms ofproduct life and luminous efficacy.The output oflow-pressure sodium-vapour lamps (often seen above pedestrian crossings, in a monochrome yellow light) is approximately 100-180 lumen/watt, a fluorescent lamp approximately 80-100 lumen/watt (but with white light) and a tungsten halogen lamp approximately 15-22 lumen/watt. (This is why they are hardly ever specified in public lighting schemes). There is a conflict between the efficiency and the quality oflight emitted by a lamp: the better the light quality (essentially the colour rendition and the colour temperature), the lower the luminous efficacy.Finding the right balance between these opposites is one ofthe goals ofgood lighting. Lamps also influence the design ofthe luminaire. Their shape and size determine the luminaire head - all lamps used in the public domain require control gear that needs to be accommodated in addition.

48

Outdoor lamps:

Electrical power (watt) from - to

Luminous flux (lumen) from - to

Luminous efficacy (lumen/walt) Colour rendition from - to

Colour temperature

18 - 15

1,350 - 5,200

75" - 93"

18

WW,

Tabular fluorescent lamps three-band lamp 0 26

nw, tw

Compact fluorescent lamps 2

2-tube lamp

18 - 57

1,200 - 4,800

67 - 88

18

WW,

nw

3

2-,4- and 6-tube lamp

5 - 57

250 - 4,300

50 - 75

18

WW,

nw

50 - 1,000

1,800 - 58,000

36 - 58

28,3

ww, nm

ww

Mercury vapour 4

ellipsoid

High-pressure sodium lamp 5

with double burner

50 - 400

4,000 - 55,000

80 - 138

4

6

with T-cap

35 - 100

1,300 - 5,000

39 - 52

18

ww

7

with xenon

50 - 80

3,600 - 6,000

72 - 75

3

ww

8

tubular

35 - 1,000

1,800

51 - 130

4

ww

18 - 185

1,800 - 32,000

- 130.000

Low-pressure sodium 9

tubular

100 - 178

Metal halide lamps 10 tubular (without illustration)

250 - 2,000

20,000 - 200,000

69 - 100

lA,18

nw, tw

11 with T-cap

35 - 150

3,400 - 14,000

87 - 95

18

ww

12 douple capped

70 - 400

6,300 - 36,0000

90 - 91

18

ww

0.7 - 1.5

18 - 27

13 - 23

18

LED 13 LED

Lamps (not to scale) 1

Three-band phosphor fluorescent lamp

2 3

Compact fluorescent lamp Compact fluorescent lamp

4

Mercury-vapour lamp

5

High-pressure sodium lamp, with double burner

6

High-pressure sodium lamp with T-caps

7

High-pressure sodium lamp, with xenon

8 9

High-pressure sodium lamp, tubular

11 12

Metal halide lamp

13

LED

Low-pressure sodium-vapour lamp Metal halide lamp, double capped

49 Process: Lamps and Luminaires

Luminaires, poles and attachment points: Requirements

The term "luminaire" originated in the field ofartificial lighting and is imprecise in the context ofurban light. When the term luminaire is employed for external applications supported on a pole or suspended, it frequently denotes the luminaire head alone. On the other hand, the "fasteners" always present a challenge for innovative solutions during the planning processes: although inconspicuous from a technical perspective, these components are essential and must be distributed correctly. How and where can new luminaires best be mounted? This question relates to power outlets, that is, places where electricity is readilyavailable. Often these are not where they are needed for the new system. A decision must be made on whether to re-position existing poles and overhead wiring and the predetermined mounting heights, distances and maintenance schedules, or whether a compromise with regard to positioning and attachments for the next 20 years would ultimately be more sensible. The latter choice does, however, go hand in hand with a technically less than ideal lighting solution. While the range ofavailable luminaire heads is wide, there is little variation in the selection ofpoles on the market, which are frequently mass-produced standardised products without notable aesthetic qualities. With the exception of historicising models, the common approach of contemporary solutions is to make objects in the public realm as inconspicuous as possible. Some designs ofrecent years seem to forgo even this and simply incorporate light at ground level or seek eccentric pole solutions. In the hands of designers, the grey lamp standard has been transformed into an urban sculpture. Both approaches seem to be a passing fad offashion. "Construction kits" for luminaires and accessories, including poles, offer a promising alternative. This "modular" approach to the installation ofluminaires has in recent years been adopted by the lighting industry; production and distribution has become more flexible. A multitude oftechnical solutions is now available which relevant manufacturers can easily insert into various luminaire types. By employing this method an experienced lighting designer can Outdoor luminaires (not to scale)

precisely define the light for each specific location without having to revert to serial products, and still be able to rely on continued support from the manufac-

1

Catenary luminaire

2,3

Flexible spotlight

4

Floodlight

5

Kofler luminaire

6

Globe luminaire

7

Pole-top mounted luminaire

8

Bollard luminaire

9

Indirect luminaire with spherical cap reflector

10

Pole mounted luminaire

11

Whip luminaire

12

Recessed floor light

50

turer.

Family of luminaires: Advantages

To draw on a "family ofluminaires" is a tried and trusted method. The basic idea is to provide the city with a lighting system that is homogenous in appearance,

The mounting heights define the atmosphere, but also the cost effectiveness of a project.

while at the same time gaining technical advantages from a coordinated group ofluminaires. It is much easier to maintain and operate such a "family" than a multitude ofdifferent luminaire types. Moreover, the quantities required over a number ofyears enable manufacturers to make attractive offers. Developing a family ofluminaires, issuing a tender for it and integrating it into the townscape, requires careful planning and deliberation by the lighting designer. The luminaires will represent one of the few homogeneous characteristics of the site. Hence, they give identity and have a unifying function. A family ofluminaires may also include a standardised pole for different lamps ofvarious wattages and mounting heights. Arranged along differently dimensioned grids and fitted with luminaires they unite to form a continuous framework. The groups should comprise luminaire positions from ground level up to 16 metres in height and thus cover the entire range ofconceivable lighting technology, beginning with bollards at a height of one metre and offering a variety ofpole heights (4, 8,12 and 16 metres respectively). Poles can also accommodate additional functions within the town or on the site. One can either allocate a special location for each function (traffic lights, road signs, information boards, fire alarms, technical information, etc.) - as is commonly done in Germany - or bundle these functions in one place, on suitable poles, as in New York City. The "centralised" solutions are generally confusing, whereas "decentralised" solutions lead to an unattractive "forest of signs" or "over-designed" proposals. The ideal family ofluminaires should cover as many standard lighting functions as possible. A set ofhierarchies relating to mounting height and emittance characteristics, also referred to as light distribution, emerges in accordance with the use to which each luminaire is put. These hierarchies are then applied to the entire site or project area. The masterplan thus lists a comprehensive catalogue oflight scenarios which serve as the basis for creating a varied and harmonious overall design. This includes the matching oflight colours in the "white" range oflight. Colours change from cold, daylight-like tones to warm tones, similar to those ofan incandescent lamp. Where warm colours dominate, in low, pedesStandard luminaire heads for poles developed for a specific project.

trian areas, the light will appear natural and intimate. Colder light colours are

51 Process: Lamps and Luminaires

suitable for high mounting heights and produce uniform, anonymous light for road traffic areas.

Luminaires as design elements: Prospects and potentials

Poles and luminaires in the public realm occupy a rather ambiguous position. Benches, bollards, litter bins - all these elements ofstreet furniture have clearly defined functions and are comparatively easy to construct. They can be positioned fairly independently within the city. Luminaires, on the other hand, require electricity, they must be placed in specific locations and they are absolutely indispensable. The city will still function without seating and bollards, but not without lights at night. Hence, public lighting spans across a wide and branching urban network that has grown over time. It is one of the details that characterises urban life'. Each city creates its own light with its own luminairesthe difference becomes obvious at second glance. The appearance ofpublic lighting in Paris differs from that in London or in Hamburg. It is therefore local

~============8

in character. The design and installation of characteristic luminaires and poles could, if the city chose to promote itselfthrough light, represent an opportunity "in the detail". It could be one ofthose last finishing touches that reinforce a unique idea. Since the appearance ofurban streets is strongly influenced by the large number ofluminaires, a comprehensive scheme would contribute to improving the streetscape in the long term and also help to raise its profile. Introducing a customised luminaire that operates on the available, existing technology would be a highly attractive approach. This could be worthwhile for cities and for manufacturers, if fixed quantities are agreed over several years. Next, more attention should be given to the poles; they could be more than mere supports for luminaires, but could double as traffic lights, luminous signs and information posts. This would save installation costs and keep the city-

Competition entry for New York City. Poles take various elements: Lights, traffic signals, street signs, litter bins.

scape simpler and less cluttered. To introduce a pole ofoutstanding design quality, with all the necessary technical gear, would provide a new stimulus in the monotony ofthe existing tried and trusted lamp standards. Traditional lanterns fitted with modern lamps can be found in many cities. The glass sides of these luminaires expose naked lamps producing glare. They represent a technical contradiction to their historical housing. Without sophisticated anti-glare lamellae, diffusers or reflectors, such luminaires do not work properly and spoil the effect oflight in the urban setting.

1 On this topic, see Virginia Comer's observations in the slim volume: Virginia Comer: Streetlights Urban Details Los Angeles. 2000, self-published

52

An alternative to installing location-specific systems is the use of"invisible" luminaires, in which both the luminaires and the poles are designed to be as inconspicuous as possible so they tend to be overlooked. The rationale behind this approach is the elusive dream ofcreating a timeless design. Many of the luminaires on the market today are either historicising or trendy in design; it remains to be seen whether they will still be popular in ten years' time.

Controlling urban light: Future prospects

In the future, light in cities, just like that in buildings, will be largely centrally controlled and, at the same time, locally managed. It will be possible to set the times and time frames for the operation oflighting systems, while simultaneously controlling the "local" brightness or darkness. The costs for such improvements are difficult to estimate at present. For over a century, analogue networks have been built and safeguarded. The power load is distributed across a vast area and to a large number ofconsumers. Frequent voltage fluctuations make it difficult to control whole systems. As a general rule, switching options for existing electric circuits are limited to onl offsettings that do not really offer control. Local networks are often activated or switched off via twilight switches.' Also time switches are employed so that parts ofthe system may be switched off during the second halfof the night, when there is little traffic. The technical implementation ofnew digital control systems ultimately rests with local power companies. Future light scenarios, such as twilight lighting, night time lighting, event lighting and security lighting, should be defined by the lighting designer.

2 In Germanythe valuesare stipulatedby DIN5044, part 1.Current regulationscan be foundat www.baunetz.de/arch/ bauregeln/index.htm.

53 Process: Lamps and Luminaires

We are all familiar with this experience: a few places catch one's eye, time after time, or they are part of one's local context - whether by choice or not. Places and landmarks, encountered by chance that nevertheless influence our behaviour. We may find ourselves moving in one direction or another, simply in response to a preference or perhaps because something is not quite right with the light at night ... What follows is an illustrated presentation of these hotspots of perception, offering starting points for possible improvement of light in cities through concrete solutions. They invite spontaneous contemplation of every-day lighting phenomena that affect city dwellers.

55

Travelling by Car

Main roads and side streets

Away from the large traffic arteries, we enter into the domain ofthe "hoods" where the inhabited and inhabitable city unfolds along the side streets. Immediately, a sense ofbelonging arises - an issue not to be disregarded when planning new urban quarters. The quality ofliving and the safety ofa neighbourhood increases proportionally to the degree ofidentification felt by the residents.The provision oflight plays an important part in a neighbourhood. Light should produce a feeling ofsecurity, generate a sense ofbelonging and exude comfortable warmth, similar to that in our own living rooms. A lot can be achieved with low lighting points, but this would increase the number of luminaires that need to be maintained. Warm white lamps, such as metal halide lamps, are suitable. Their light is less dingy than that cast by (yellow) sodiumvapour lamps. Another factor to be considered is that lamps should emit light at low elevations. Streetlights must not shed bright light into nearby living rooms. Finally, aesthetics playa part in choosing a luminaire: its shape. It is regarded a professional blunder to select luminaires on the basis ofform rather than functional merit, although optimised technology and attractive design often go hand in hand. When re-designing the lighting ofa neighbourhood, however, it may be expedient to select distinct poles and luminaire heads. This is not to suggest that every historic quarter should be equipped with reproductions ofluminaires in the style ofSchinkel.

56

57

Typology, Travelling by Car

58

Bridges

Bridges are most often erected at exposed locations. It is in the nature of the thing and inadvertently marks them as desirable objects for illumination. Illuminated bridges are eye-catchers, especially when they can be seen from a distance. Obviously, investments for lavishly luminous bridges are high. As a rule, illumination is restricted to the outline or contour ofthe bridge, since it has no surface area to speak of, except for the road itself. But ifthe light is directed onto the piers or pylons, this may result in the height or width ofa bridge being overemphasised. Illumination of the load bearing structure, in addition to the road lighting, is generally more unobtrusive. Narrow-beam spotlights attached directly to the structure offer the best solutions. Specific structural features must be taken into account, in particular with large bridges. They can seriously hinder maintenance operations. Attachment points must be easy to reach. Small bridges across streams and rivers are frequently too brightly lit. Atmospheric reflections upon the dark water should not be destroyed by too much emphasis on the bridge structure. Small bridges in parks or across moats in European cities are often welcomed as objects of illumination - and overdone because there is little else. The mere presence ofa bridge in a park is no reason to illuminate it.

59 Typology: Travelling by Car

Roundabouts

An ingenious invention: the roundabout. It was first tested for urb an traffic in New York City and Paris approxima tely one hundred years ago and has been employed ever since. The fact that roundabouts eliminate many of the dangers of tr affic is widely accepted today. Consequently, Europe has seen a full-scale inv asion ofnew roundabouts in past years. The more useful the periphery of the circle, the more superfluous is its centre. An obvious treatment would be to furni sh the island with artistic designs offlower borders, large sculptures or traffic fixtures. A further practical solution is the erection of high lighting masts th at illuminate the passing traffic from the centre. The current pr actice oflighting has reverted to giving favour to the periphery of the roundabout - the junction with approach road s. It accentuates the crossroads an d, alm ost as a side effect , lights the roundabout, chiefly as a result ofthe standard rad ii applied to roundabouts: the intervals between luminaires are closer than on straigh t roads and "uninten tion ally" increase the luminance.

60

61 Typology: Travelling by Car

62

Traffic signs

In the age ofsatellite navigation, illuminated traffic signs appear like the shining accomplishment of a past and unremitting traffic euphoria. They have developed into ubiquitous icons, brought into the cities by growing traffic volumes during the last century. On their own they seem comparatively harmless, like the luminous stop sign found at a road junction. Accumulated, for example on masts, they take the shape ofskyward-reaching sign trees. The large-scale signage on gantries reaches almost cinematic dimensions along our modern expressways. Traffic signs, illuminated like lanterns from within, stem from more prosperous times. They have the advantage ofbeing glare-free and evenly lit across the surface; the fluorescent lamps are high-maintenance, however, and replacing them involves the time-consuming assembly ofthe luminaire body. This is why signage erected and lit by spots was introduced. The largest signs are found above and alongside motorways. Retro-reflecting signage was introduced specifically for situations where the distance between sign and driver is short. Modern headlights are sufficiently bright to make the signs, often mounted at eye level, legible. Luminous signs introduced a specific colour range to the urban night. In France, this is an unassuming black and white; in Germany, the nominated RAL colours dominate, adding a new layer to the urban scenery. What are the trends? Contemporary approaches attempt to significantly reduce the forest ofsigns in the city centres. The excess ofprohibitions' commands, information or other signage on any corner should be cut to a minimum. Their effect is too limited and the appearance too intrusive. At major intersections and interchanges and along expressways, however, illuminated signs are here to stay. They are the Buddhist Pop Art ofmodern road traffic: illuminated and memorable.

63 Typology: Travelling by Car

Multi-storey car parks

On film they attract much interest: multi-storey car parks guarantee tension. These inhospitable interiors, constructed ofsteel and reinforced concrete, are the ideal setting for criminal action, for getaways, ambushes, labyrinths ofchill and fear. These associations are by no means unfounded for car parks are about as appealing as bunkers. Motorist driving in and out experience them as temporary tunnels because of the difference in light levels. Slow driving helps the eye to adapt to sudden darkness or, conversely, to blinding brightness. During the day, the lights in the interior are brighter than at night. There should be no "dark corners" in multi-storey car parks to ensure visibility ofpedestrians at all times. More light is also required for designated parking spaces for women. Some car parks are more susceptible to glare - from the perspective oflighting technology - predominantly in areas where sunlight enters the decks and falls directly onto the driving lane. Artificial lighting levels must be twice as high in these areas than in other places.

64

65 Typology: Travelling by Car

66

Car parks

Car parks are much sought after and for their users the starting point for visits to the city. Even now, no one really attends to the light in these spaces. Light emitted from as few sources as possible, mounted at the greatest conceivable height, would be the most economical solution. If there are residential buildings around the car park, compromises regarding mounting heights must be made. Good examples no longer employ diffuse orange-coloured sodium-vapour lamps, but utilise metal halide lamps, which have better colour rendition and a warmer light colour. Access and egress points are clearly marked with light and, in the best case, low light will lead to them, even over a long distance. In the worst case, the optics are ofinsufficient quality. Car parks are often the poor cousin ofexterior lighting design. This can also be said ofthe design quality ofpoles and luminaire bodies. Car parks demand a lot ofimagination on the part ofthe lighting designer.

67 Typology, Travelling by Car

Petrol stations

They have evolved into distinctly lit landmarks, not only for drivers. Conspicuous green bands of colour, blue or orange bands against the night sky catch the eye. But it is not the silver lining on the horizon that we see. Far from it: justas the overall appearance ofpetrol stations exudes cheap plainness, the lighting conveys a lack of design investment. Offering neither orientation nor variation, it is simply and plainly as bright as possible. Driving into a petrol station is like driving into a light aisle. Steps for initial improvements would be to introduce unobtrusive light in order to integrate these structures into the urban environs, and to make the terminals more user-friendly by directing light at the petrol pump and the waiting cars, rather than against the night sky. This would also contribute to the visual enhancement of cities. Flying over urban areas at night, one firstly notices sports fields and then petrol stations, their extraordinary illumination bearing no relationship to their significance within the urban fabric.

68

69 Typology, Travelling by Car

70

Stop and go

A lonely cone oflight in the darkness, in the middle of the countryside, constantly moving forward. This image ofa car moving through the night is fascinating because it holds many associations. In the city, however, this imagery is reduced to a limited vocabulary. Breaking, starting, rolling, accelerating and stopping transforms the moving car lights into a chain reaction offew signals. At the front of the vehicle are directional lights for orientation, at the rear red warning lights. When the flow of a line of cars ceases - in a traffic jam or at traffic lights - the all too familiar long queues of these old "lanterns" form into a flashing parade oflights.

71 Typology: Travelling by Car

On Foot

Squares

Public lighting originated in the urban squares and along main roads, in the important spaces of European cities. First illuminations were sensational displays, intended also to demonstrate the grandeur of cities at night. The illuminated squares of Paris resembled the halls ofVersailles, bathed in magnificent candlelight. At that time, nocturnal light was at a premium. It was almost entirely dark, hence the effect. Today, few urban squares live up to these expectations, as the facades defining the spaces usually have brightly lit shop fronts and illuminated advertising panels which determine the light atmosphere. Good lighting will not turn around this commercial trend - which does have a certain appeal- but with the deliberate treatment ofdarkness it may achieve a great deal for traditional city centres. The square itselfmust be sufficiently lit, so that people will want to walk in it and linger in its brighter areas. The characteristics ofthe city centre, however, shape the night-time illumination along the square's periphery and contours; with restrained facade illumination (reflections should not light the square) and a few brighter accentuations ofthe urban architecture. Artificial light has not been available for long - it is an instrument that needs to be employed carefully, an addendum to the manner in which flaneurs and consumers experience the city. It could become special once again. At night, new lighting should not come immediately to the fore; instead, its ongoing presence should revitalise urban life. Although accomplishing this while satisfying individual interests is one of the most difficult tasks, it will achieve the most sustained reward for all parties involved.

72

73

Typology, On Foot

74

Footpaths and sidewalks

Footpaths in European cities greatly differ from country to country. Lighting that is especially designed for pedestrians is a rarity and most footpaths and sidewalks are therefore illuminated by existing street lighting. Paths in public parks - or in pedestrian precincts - are sometimes lit especially for pedestrians. Special lighting is often applied to the boundary between public and private spaces. As soon as one leaves the street to approach a private building, one should be able to see the building and its entrance. The light on the way needs to be as low and direct as possible. Ideally, it should be grazing light directly above the ground. This ensures that light does not disturb the pedestrian's view onto the ground and into the distance - even though it fulfils its function (5-7 lux are the recommended value). Light directed at the ground does not cause glare or obscure the view. Ofcourse, more fittings are required than in a lighting scheme that is based on the common, wide-angled luminaires on columns above three to four metres in height. The usual traffic lighting on streets and paths is intended for cars, not for pedestrians. Although we have been getting around on foot for as long as we can remember, this might be the very reason why so little importance is attached to it and to the lighting of these areas. The conventional light in pedestrian precincts is primarily designed for safety ; danger and passers-by should be recognised as early as possible. Additionally, light should provide orientation. This is now increasingly achieved through the use ofrecessed elements which have become smaller, less expensive and more durable with LED technology. The first models powered by solar energy, independent of electricity circuits, are available for orientation light Light points, lines, hatches or nets may be "drawn" with light in pedestrian areas. As an aside, [the artist] Daniel Buren succeeded in doing just that with his installation at the Palais Royal in Paris; in fact he showed us how to do it 20 years ago.

75 Typology: On Foot

Trees

Rustle - rustle. This is the sound ofautumn in Walt Disney's comic strips. Bare trees reveal their natural structure ofstem and branches. It is fascinating to see the grown order of a tree contrasting the clearly structured facades and squares. This is why it is popular to light trees . Light on trees is usually emitted by buried luminaires. This is the method currently established for lighting trees. When using buried luminaires one needs to make sure that they are not positioned along lines ofmovement. The glass can be hot. Some time ago, the technique of training spots from a distance was common practice. It gave the tree a sculptural quality and cast interesting shadows. A third alternative is to place the lights on the branches lighting the tree from within. This is the most beautiful lighting option, but the fixing ofluminaires is often difficult, the necessary wiring unsightly and the supply line conspicuous. Light colour is an important aspect oflighting trees. Most suitable are neutral white halogen metal vapour lamps (HIT). Warm white or sodium-vapour lamps make the tree and its leaves appear grey. If one chooses buried luminaires, it is important not to place them too close to the trunk. The growing roots could displace the fittings , and trees do not like the heat. If the surroundings are dark, a little light is sufficient. When seen from a distance, the subtle lighting of trees in open spaces and parks can be extremely attractive. The site will gain in "depth", the trees will compose the silhouette. Trees planted in clumps can be visually grouped together using low lighting near the ground and thus transpose the design intention ofparks or courtyards "into the night".

76

77 Typolcgy: On Foot

78

Facades and illuminated advertising

Illuminated advertising is an invention ofthe electrified and modern city. Unique at first, now found everywhere, it is firml y imprinted onto the modern urban imagery. Almost all that shines from buildings at night is advertising. It seem s that no one wants to do without the variety that has developed over time. In the beginning it was the attractive and almost forgotten neon light with glass tubes and high-voltage systems. In spite of their triumphant advance in many European cities, illuminated ads are subject to planning approval, and rightly so. They are prohibited in some districts. Noone wants to see ads reflected in LakeZurich or in Hamburg's Alster. The use oflight for advertising purposes should therefore be regularised with the specific ambience and location in mind. What if facades are turned into advertisements, when the external skin ofa building mutates into some sort of screen? In German cities one occasionally encounters vast advertising boards behind glass, lit and mounted in the interior of the buildings - a practice that cannot be prohibited. Plasma and LED screens can now cover entire elevations. In Seoul , elevations are being plastered in screens to such a degree that they demote the facades of Piccadilly Circus in London, Times Square in New York or the squares ofShibuya in Tokyo , into museums ofilluminated advertising. While neither the screens nor the messages are very bright, the cinematic scale - reminiscent ofthe renaissance of drive-in theatres - tends to displace architecture. The built language of the city is dying. When individual facades that are suited for light experiments are transformed into a "luminous" theme, the results can be alluring indeed. The same is true for strategies that utilise light deliberately in conjunction with architecture and the urban image . In recent years, there have been a few notable attempts to animate high-rise buildings with individual lighting scenarios, although not all of them have been successful. In Hamburg, illuminated goal posts were placed on high buildings on the occasion of the Football World Cup 2006. A little gimmicky, but these things happen. In Europe, respectable light experiments mostly involve facades, but the Chinese love light to be "on top", in all colours. As long as we have a choice and buildings in their own right are the centre ofsuch experiments, rather than the light on them, such approaches may succeed. Unlit, monotonous granite facades, with their formally chartered claim to perpetuity, cladding steel skeleton structures, are hardly beautiful. Large-scale lighting schemes offer a vibrant alternative.

79 Typology: On Foot

Shop windows

One simple, basic rule applies to the general lighting ofshop windows. The horizontal plane, the ceiling, produces the basic illumination while accents are placed on the vertical surfaces, the walls . In principle, there is nothing to be said against this formula. But its calculation is based on an isolated point in the centre of the space. It omits important factors beyond the four walls of the premises. Neither does it consider the different light conditions in the day and at night, nor what is in front ofthe shop. Seen from outside, from the shopping street, display windows compete with one another. Competition reinforces the tendency to assume that attractiveness increases with light levels . This is often coupled with over-dimensioned illuminated advertising on the facade ofthe building. The effect on the passing consumer is distracting rather than enticing. Given the unanimous consent among all the merchants in a district, a lighting design guide could be commissioned and presented. Another conceivable idea is to formulate an agreement that sets limits for the brightness of displa ys and restricts advertising icons to facades or to high locations only. The light quality achieved in this way would be an inexpensive and quick way ofimproving any high street. Shop windows with strong, predominantly horizontal light that is not directed at the walls appear marginally brighter than the ambient lighting. This avoids reflections. Some light should also be visible in the depth ofthe premises. These soft transitions with light accents present the goods more effectively than sheer brightness. The choice oflight colour is determined according to the goods on display. A shop for technical products will hardly use soft, expensive narrow beams ofhalogen light; and vice versa , a fashion store would rather do without up lighters fitted with cold white lamps.

80

81

Typology: On Fool

82

Underground stations

Underground stations are not places where one wants to linger. The common, typical tube-like architecture ofsuch subterranean spaces for rail traffic are very low and long, often displaying the laboured efforts of design accents on walls and a recurring rhythm ofpillars, furniture and signage. The only promise of some entertainment lies in studying the advertising boards. The choice and execution oflighting - in most stations without any daylight at all- underlines monotony; seemingly endless strips offluorescent luminaires placed along the platforms are boring for the observer and make orientation difficult because ofreduced contrast perception and adaptation. The exclusive use of direct light ofgreat luminance levels further diminish the visible height of the space and make it appear even deeper. Generally, the monotony in the selection oflight sources, the type oflight and light colours precludes contrast-rich, accentuated lighting that sets up a hierarchy ofspaces. The spatial geometries of these tunnels, in particular, represent an as yet undiscovered challenge for creating good lighting design for users below ground and there is also ample room for improvement in above-ground stations as well.

83

Typology: On Foot

Boulevards

Rome was to Antiquity what Paris was to the 19th century, New York to the 20th century and, possibly, what Shanghai or Mexico City are to the 21 st century: the embodiment of the city. Cities are characterised by a network of streets. In city centres some streets are displayed in their full local splendour. Modern boulevards leading into the centres take on a representative function; they are a European invention of the 19th and 20th centuries. Their width facilitates the differentiation of public light in three zones: light for traffic, light for pedestrians and light on buildings. Each ofthese types oflight has a different function that should not compete with, but complement the others. Light on the street must be uniform, just like light on footpaths, only a little brighter, warmer and "denser"; shop windows should be individually designed, the light on facades and illuminated advertising should be as homogeneous as possible. Great importance is attached to the design of boulevard luminaires. The luminaires selected for these areas are special, as is the planting and seasonal lighting at Christmas, for example. Likean urban square, an attractive boulevard is almost an internal space with carefully staggered "luxury lighting" that sets it apart from the dark surroundings . Its single light points join up to form lines and, finally, avenues oflight into the rising dawn - whose steely grey extinguishes its splendour for a few hours.

84

85 Typology, On Foot

Design Principles and Techniques What is the significance oflight in cities today? Which specific requirements should it fulfil? Who needs it? First ofall, light is important for drivers at night. A large proportion ofurban illumination is street lighting. Accordingly, the majority of citizens perceive the city at night in the light ofits tarmac routes - journeys made by car. Every evening cars join a swelling and receding stream which late at night ebbs to reveal the streets and junctions in a flat and uniform light. What are the actual light conditions citizens move around in today? Is the treatment oflight symptomatic of the behaviour ofpeople? Probably not. Light is still a contemporary issue, especially if it should be improved. As soon as it gets dark outside, most urban people are surrounded by "light sludge": the regular street lighting in front oftheir homes primarily noted for its largely undifferentiated brightness, and the generally diffuse, sometimes flickering light inside their flats. The television set often takes on the function ofa campfire, a light people like to gather around, like in ancient times? This paradigm is the false reasoning ofmany ofthose people who are concerned with light. More luminaires automatically produce more light and, hence, better business. As with cars - there are simply too many in the city. Still, they are fun. However, this does not improve conditions. Improvement will not happen unless urban light is designed with care, and in specific areas perceived to be special and designed to levels over and above high standards. In working towards this goal the available options of designing with light must be fully exploited. Because light can substantially improve the existing situation and remain fascinating this provides a definite opportunity for the wished-for and long overdue revitalisation ofurban life. Light should be offered to the urban dweller and invite him "to be in the city". Two partly conflicting strategies may be adopted to achieve this. One is aimed at the promotion ofcontemporary event culture, the other at the enduring differentiation of urban lighting, practically an endorsement of the townscape. Both approaches offer significant potential for urban lighting. Events draw people into the city and make it vibrant. Unlike traditional performances at the opera, theatre and cinemas, event visitors actually participate in the activities, sometimes they are the event. Well-known examples are the "Love Parade" or the "Christopher Street Day" celebrations. Such mega events are pure publicity and they are focussed on city centres. The impact of this "festivalisation" ofurban life, as critics name the phenomenon, is also felt at night.'

Waterfall at the EXPO 2000 in Hanover: Water and light produce a vibrant effect. Unfortunately more and more German cities shun the running costs of fountains and water features.

1 Extremely convincing argumentation by Gerd Held: Stadtbeleuchtung, In: Regina Bittner (Ed.J:Urbane Paradiese. Zur Kulturgeschlchte modernen VergnUgens, Edition Bauhaus, Campus Verlag Frankfurt/NewYork 2001. Reader for the exhibition "Paradies der Moderne" at the Stlftung Bauhaus Dessau 2001. Excepting Schivelbusch, Held Is one of the few who attempted to explore the topic of urban illumination from the perspective of cultural history.

86

Temporary "event lights" act as a catalyst for activities, spurring the participants on. These lights are often coloured and highly mobile, like in the theatre. The city and its squares are transformed into a stage, the facades form the - admittedly unchanging - backdrop. There are in -between forms in which event illumination is firmly built-in and repeated every night, or at preset intervals. The illumination ofthe Eiffel Tower in Paris illustrates this. Presently, Parisians are transforming their landmark into some kind ofglittering lollipop for five minutes, on the hour, every hour. Before the glittering starts, the tower is bathed in a red and yellow light. When asked, many Parisians voice their approval. They don't mind the tower being temporarily turned into a colourful plaything. The second approach refines urban lighting to increase its intensity. The seminal idea is to bring to an end the current practice ofseparating the lighting of roads and pedestrian areas, facades, shop windows and advertising panels. The objective is to obtain an integrated appearance which is characteristic ofthe local environment. This is more sophisticated than simply playing with colours, and much more difficult to put into practice. Principally, the lighting designer moves along a two dimensional design strand. He works with the dimensions of time and space. Artificial light for exteriors is mainly relevant at night. Evenings, mornings and seasonal changes bring many recurring transitional situations. The light shifts. Furthermore, the need for seasonal light arises. On the large scale, access to urban spaces is gained via the city's traffic arteries. Reducing the scale brings up questions ofpotential perspectives and differentiation. Reducing the scale even further will theoretically take the perspective right down to the scale ofan individual's body and his immediate environment. It could be an urban space which can be grasped "on foot", or a car in a traffic jam - all are common urban situations. New lighting should "reinvent the night" for the visitor to the city. This, though slightly exaggerated, is the actual objective. Marketing people would present this as a desire to prolong the time people spend in the city. Revitalisation ofthe renowned nightlife ofthe "Roaring Twenties" immediately brings to mind the legendary times ofpublic light that we now see repeated in China and the "Tiger States" ofAsia. Light ad infinitum. Recent newspaper articles report that Shanghai is thinking about switching offthe illuminated advertisements because of insufficient power supplies to run them. Such global trends are real. They are based on our fascination with brightness, our desire to turn night into dayundoubtedly an attractive prospect. Well thought-out design, however, is based on darkness, the opposite. It conceives light reciprocally, not glistening, colourful, bright, competing, but as an Funfairs and their "high" attractions create a distant impact with light.

87

Typology, Design Principles and Techniques

initialisation into the changing times ofday and the seasons. This is not to say that the city should be dark. It means that the lighting designer will not only meet the requirements of urban spaces, but also consider those of the natural light conditions. The contemporary lighting consultant's design concept does not stand in isolation, but aim s to devise a scheme that integrates the citizens, the city and the times of day. Anyone designing with light should, at the outset ofa project, appreciate the day and night cycles ofthe site. The best starting point is twilight. Lights are turned offin the morning; long shopping hours have shifted most of the city's activities to the time around nightfall, into the "blue hour", or later, depending on the season. In the early The roof of the station lor ecour l "hovers"

even ing , urb an lighting can be applied selectively to the most important urban

above the bus stop and fo r ms a t ranspar-

squares and buildings, the well -known focal points of the city. The next step

ent counter part to the stati on hall.

sho uld concentrate on ped estrian areas, access and egre ss points, creating "gateway situations" that indicate the direction in which the flux of urb an life is moving. Finally, the street ligh ting is switched on. Lights set in gradu ally, rendering the n ight attractive an d safe. Onc e it is completely dark, the planned hierarchies ofl igh t are fully sw itch ed and orientation is no problem. The immediate surro undings can be overlooked at all times, there are no dark corner s. Above, from the first or second storey onward s, light becomes noticeably reduced, defining a clear but sheltering overhead space. Most of the attractive luminosity is a result of reflections on different materials, including the paving. Lamps emit gradations of white light. Some light is emitted from the interiors ofbuildings . The levels should be homogenous, the shop windows not glaringly brighter than the space outside them. Most importantly, they should not cast direct light into the street. Colour can be added by the light on the goods on display. During the course of th e night, th e accent lighting th at st arted the seque nce ofillumination fades. The overall lighting that instils a sense ofsafety rem ains until dawn. Thi s is a po ssible scenario for complete 24-ho ur cycle of day and night. Chri stmas lights have always been the archety pal seasonal, temporary illumination linked to time ofyear and commercial sales periods. It is very cost inten sive to run, but enjoys increasing popularity w ith the public. Many pos sibl e design theme s have been aired: recently, temporary lighting ofpools, wa ter features and fountains, or parks has once again become popular. It offers a reminder of a permanent Baroque staging that, 250 years ago, would have been produced for a single evening using thousand s of candles I . In a seasonal cycle they represent temporary illuminations, preferably repeated, with alternating switching times. On the other hand, fixed illuminations for seasonal amusements, such Glow ing heart s at the Tivoli in Copenh a-

as ice rinks or temporary pools and beaches , may become special attractions.

gen: Light in g desi gn and light art have been an inher ent part of th e park sin ce the 1920 5.

88

3 Prior to the 17th century, parties and theatre productions almost always look place during the day.

Potential design details can only be discussed after examining the second approach to good lighting in cities, the spatial dimensions. It denotes the essence of the design scenario light - space, that is, the disruption in the movement of a passage into the city and the respective potential afforded by this. The disruption is marked by the traveller's changed mode of transport, from driving by car (aeroplane, train, public transportation) to walking. The opportunities arising from it are limited to the inner cities and certain shopping districts. These are, at present, the spaces and districts in which, subject to the will ofthe municipalities, chambers of commerce, public private partnerships (PPP)or Germany's proposed business improvement districts (BID), new urban lighting is to be established and intelligently planned. Essentially, they are the old market squares in a new guise. Regrettably, the design oflight for exterior spaces is divided into two areas, The water jets in this field of fountains

street space and pedestrian space. But this is exactly the wrong thing to do; it is

can be switched off when the market is

precisely this separation that must be overcome. The design should accomplish

held in front of the Town Hall in Miltenberg.

a continuous concentration in density ofthe light effect. The intensity oflight could increase towards the centres. Not to say that everything should become brighter or garish. The key concern is nuances oflight, its presence in streets and squares in a relative sense. The existing light is sufficient to make the existing environs adequately visible so that anyone walking the streets at night is able to see his immediate surroundings, metre by metre, and feel at ease. From a distance, light in the centres must be sufficiently bright to set them on display and to exert a constant pull. Also, light demarcates previously defined areas. The inclusion ofstrong local light should be possible in exceptional situations or "randomly" without disrupting the overall appearance. Existing installations and systems are a world away from this.

A small fountain in Hamburg Bergedorf creates a cosy atmosphere.

89 Typology, Design PrinCiples and Techniques

Lighting paths and facades: Design techniques

Every luminaire has an IP rating denoting its protection measures against moisture, dust and other influences. Several lamps and some types ofballast only work in a limited temperature range and will not start in frosts, for example. Suitable luminaires are oftwo groups: luminaires that light ground areas and luminaires that light facades. Additionally, light is emitted from buildings and shop windows, which is more difficult to control.

differentiated facade illumicatenary luminaire

City of Braunschweig: The black plan illustrates the functional illumination in the square and adjacent streets in conjunction with

facade lighting.

90

•

pole luminaire, mounting height 3.5-4.5 m

pole luminaire for street lighting, mounting height ca. 7 m

nation

light from the interior

tree

water feature

1)

General lighting for traffic areas

The quality oflight is largely determined by the mounting heights and positions ofluminaires. Luminaires may be installed on poles , on overhead wires or on buildings. Poles are the easiest solution, they are generally accepted, but tend to be "in the way ", and they have few sensual qualities. In most cases overhead wiring permits the best positioning ofluminaires. But wires are difficult to place because the building owner's permission must be obtained for their installation and it is not always possible to find suitable anchorage points across long distances. Obviously, the maintenance ofluminaires in the middle ofthe road is more difficult than ofthose along the edge. Luminaires mounted on facades provide a simple solution for narrow streets. Where exactly luminaires are positioned in the traffic area is ultimately a question of design and cost. The technical requirements are clear-cut. The greater the spacing between masts and the higher the luminaires are mounted, the more anonym ous, general, tiring, but also glare-free the light will be. A variation in mounting heights and luminaire positions helps to animate the townscape. 2) Lighting for facades - light close up

Old lighting systems were used to simply brighten facades or towers with high wattage floodlights from a great distance. The more the better. The result was often impressive, but flat because the texture of the facade was no longer discernible. In a reversal ofthis technique, narrow-beam spotlights were placed close to the building. A lot ofshadow and drama was createdfrequently resulting in a lighting kitsch never intended by the architects, as it distorted the proportions offacade elements. Sophisticated solutions combine focus sed light on the facade, em itted from a distance by gobo beams, with distinguished light th at is relat ively weak and mounted directly on the building. A pos sible alternative is to appl y light very close to the facade using fibre optics . It is especially effective on light-coloured elevations .

Catenary road light ing in Bremen

91 Typology: Design Pr inciples and Techniques

l me

Boulevard: "BUrger" in Bremerhaven

Atmospheric lights for consumers

"Burger" in Bremerhaven, by WES & Partner, is a new, stretched out boulevard inviting people to stroll along its wide footpaths and befitting planting. Uniform roofcanopies define the upper limit ofthe new scheme and act as a common denominator. These continuous glazed roofs also provide shelter from bad weather and create the right scale for pedestrians. It is along these lines that the brieffor the lighting was formulated; shining in all facets ofnight-time illumination until late in the evening. Private advertising or floodlit buildings do not disturb the independent character ofthe outdoor mall, which is further supported by the secondary reflector system ofmast luminaires specified for the "small boulevard". In addition, grazing light near the ground lights the road, which is closed for traffic. The resultant alternating rhythm ofintervals generates order. The light integrated into the glass canopies corresponds with the light emitted from shop windows. This turns the pedestrian area close to the shops into a Parisian passage, which at night is defined by a 'space with light". The no longer very attractive buildings obtain a certain elegance extending their flair up to the church square, which has its own light character.

Btlrgerrneister-Srnit-Strafie in Bremerhaven had lost its lustre. Here, the design for its redevelopment.

94

The new lighting concept also lights up the surroundings: An illuminated water feature and a luminous glazed roof emphasise the length and generous dimensions of the boulevard - citizens feel safe at night once again.

'.

....•..

:

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95 Completed Schemes: Boulevard

The shining field of fountains and a light band across the church square introduce a playful element.

96

The black plan shows the key areas of the lighting concept for "Burger" Bremerhaven. The church square and market place are important features.

The combination of low grazing light with indirect light from poles provides the functional lighting of the boulevard.

97 Completed Schemes, Boulevard

Historical Facade: Hamburg Town Hall

Hamburg Town Hall in a new light: Significant improvements are: three dimensional appearance of the facade; bright base and ground floor (no glare); the power consumption of the lighting system is reduced by half.

98

Contrast on a big scale

The Town Hall of Hamburg forms the south-western boundary to the Rathausmarkt square. It can be seen from Monckebergstrafse, and at a greater distance from the Lombard and Kennedy bridges that span the Binnenalster lake. It plays a prominent role in both near and distant views ofthe city at night. In a "hierarchy oflight", a ranking ofthe brightest to the darkest buildings, the Town Hall would clearly be placed at the top ofthe list. Until recently, it was floodlit from the rooftops ofbuildings on the opposite side. This type oflight gave it a flat appearance and let the base ofthe building sink into darkness. The concept combines two new lighting techniques: - A soft, wash oflight from masts. This is ofa smaller scale than the light from the former floodlights and, with the use ofgobos night templates") produces variations in the bright-dark gradient. Lighting before 2004

- Luminaires mounted close to the facade create contrast and shadow that emphasise its three-dimensionality and complement the soft wash oflight. Together, both types oflight create a balance between the expansiveness on the one hand and the richness in contrast on the other. The roofis bathed in a wash ofcalm light; luminaires are placed between the numerous dormers. The tower is equally visible from a distance; its front is lit with luminaires positioned close to the facade and a wash oflight across its face, the sides receive a wide wash oflight. The power input ofapproximately 8 kilowatts (138 spots) for the front and side elevations offers a considerable energy saving compared to the 16 kilowatts (12 spots) used by the previous system that lit the front of the building only.

Detail of lighting before 2004

Measuring the luminance level of the tower during a lighting test

99 Completed Schemes: Historical Facade

Elevation of Hamburg Town Hall with luminaires

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Montage showing extracts from lighting tests

Supertight Compact(03)

Super light Compact(Db)

Recessed floor light

light band (recessed ceiling lumi ·

naire) in east entranceto underground stat io n: 3 x 80 W - - lighl from handrail / Positions for luminaires on Jungfernstieg

Black plan showing site boundaries

114

east entrance

POSIS

The tranquil and generous steps receive soft light from recessed side-emitting fibre optics. Low, directional light at the side-face of the steps illuminates, at a reduced intensity, the service access and ramps to the Alster. The extensive open space at the water's edge represents the entree to the lake. The calm area is kept as dark as possible to prepare promenaders for the main theme ofthis space - water. To put into practice the basic design idea, illuminance levels had to fall short of the recommended values for piers. A line ofLED,positioned 2.8 metres from the water's edge, acts as a visual indicator. In the continuation ofthe scheme, it is proposed to maximise the distance between lighting masts in the road area for design reasons. The resultant advantages ofkeeping Reesedammbriicke and the entrances to underground stations free oflight poles constitutes a conflict with the technical requirements for optimum illumination.

View of the inhomogeneous lighting along Jungfernstieg seen from Ballindamm before redevelopment

The neighbouring Alster Arcades

11S Completed Schemes: Riverside Walk

Fountains and Monuments: Schonbr.mn, Vienna

Palace Gardens Schonbrunn: The light-

Neptune Fountain in the centre of

ing concept picks up the Baroque axes to

the Palace Gardens: The fountain

avoiduniform illumination.

is bathed in coloured lights for cer-

tain events.

116

Baroque splendour

The buildings of the Viennese Palace Schonbrunn are sited across the extensive and geometrically laid out grounds. One central axis and secondary axes connect small and large buildings, lending the Palace its genuine Baroque layout. This is precisely where the lighting concept comes in; it is primarily concerned with making visible the spatial proportions. The central axis between the Palace and the Gloriette lies outside the grounds, leading along Schlossallee to the Technical Museum. Two entrance obelisks greet visitors approaching the Palace. Eagles perched on their tops frame the Gloriette that lies on higher ground to the north. Selective lighting brings out the long vistas and three-dimensionality ofthe overall site . Two symmetrically laid out fountains in the forecourt ofthe Palace place visual accents - the light on two central sculptures. The main axis extending between the fountains receives subtle light to avoid severance ofthe two. Some light is directed onto the arcades along the sides to draw attention to the park beyond. The visual differentiation ofthe north elevation facing onto the park underlines its effective illumination. While the lateral wings are bathed in bright light, the central section is subdued to make the entrance beneath the grand staircase shine even brighter. The Neptune Fountain is located in the centre of the gardens, between Palace and Gloriette. Lateral axes lead to other monuments: two fountains, one obelisk and a pavilion. The aesthetic charm ofthese monuments is emphasised by individualised lighting that, in a combination ofa bright and friendly atmosphere and visual accents , put into practice the main principles of the lighting concept. Underwater luminaires make the Star Fountain appear transparent and expansive while the Round Fountain receives selective lighting directed at its sculpture. Located on higher ground, the Gloriette "hovers" above the site. The illumination places emphasis on the exposed position by accentuating its elevation. It also picks out the architectural refinement ofthe building: the columns are individually lit, the facade, like that ofthe Palace, receives differentiated levels oflight, and the interiors are animated with light making the ceilings appear bright. The overall impression culminates in the shining transparency of the Gloriette.

117 Compleled Schemes: Fountains and Monuments

Park: Negara Bank, Kuala Lumpur

Design for the exterior lighting and facade illumination at the Bank Negara in Malaysia; plan and elevation

118

Light designed to encourage communication

Negara Bank ofMalaysia invested in a large training and research centre for the continuing education of not onl y its employees but also stafffrom other banks in Asia. The building layout is generous; it accommodates up to 400 people a day who are participating in courses ofvarying duration and attending conferences. The main building comprises offices, a library, a numismatic museum, a gallery for modern Malay painting, language labs, lecture theatres, communication areas and seminar rooms. The client attached great importance to easy communication, encouraging users ofthe building to strike up conversation and meet informally. Different external areas have been designed for diverse and communicative ways ofutilisation. Large square in front of the main entrance

The building is located on top ofa verdant hill which is reached via one of the winding roads typical of Kuala Lumpur. Here, an expansive square opens out, extending visually up to the main entrance. Medium-high walls enclose the sides of the space . In order to provide variable illumination for night-time events the square receives ambient illumination directed downwards from a system of reflectors on the roof overhang. The reflectors are made offilm with the optical characteristics ofa spherical indentation area. The light atmosphere is generated using recessed luminaires in the surrounding walls creating more elaborate zones along the edges of the square. Here, areas of planting with small pools and seating are found. Water shown on the plan shines: the pools are equipped with side-emitting optical fibres and water floodlights . Four tall multi-functional masts pro vide the ambient illumination in the front, away from the building. Additional spotlights can be mounted for events that require stage or effect lighting. Side courtyards as intimate external spaces

The west courtyard is affiliated to a small restaurant and furnished with tables. Likea pergola, a suspended net with sm all lights at the nodes creates a visual roof, limiting the height ofthe courtyard. There is always sufficient light irrespective of the arrangement ofthe tables. Light lines in the paving emphasise the graphic pattern of the landscape scheme. The east courtyard does not receive any general lighting with the exception of the diagonal bar. Luminaires are integrated into the furniture and a few spotlights are trained on the planting. The large entrance hall shines onto the outside, defining the atmosphere of the external areas.

119 Completed Schemes: Fountains and Monuments

Square: Thomaskirchhof, Leipzig

Bach's church square

The masterplan for the enclosed Thomaskirchhofin Leipzig, bustling with visitors, bars and restaurants, demanded a new lighting concept. The hitherto random, glaring and flat illumination ofthe southern church elevation was replaced by a combination offour light scenarios: a subtle wash ofwarm light from luminaires mounted on houses opposite, light close to the facade, backlighting of the church windows and lighting of the square and footpaths from existing Schinkel luminaires. All these factors work together to enhance the sculptural architecture, to integrate the church facade into the ensemble of the Site plan of Thomaskirche in Leipzig

square and to provide a more restrained, gentle and sensitive light.

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121 Completed Schemes, Square

Temporary Light Installation: Gasometer, Oberhausen

View into the 116-metre tall gasometer in Oberhausen. The luminous water cone is 50 metres tall and lit on the inside and outside. Stars are projected onto the skin of the gasometer.

122

Mystical water-light sculpture

Exhibitions in the former gasometer, a structure ofmore than 100 metres in height, benefit from its spectacular dimensions. At the "Blue Gold" exhibition on water, visitors were guided over three levels: a desert-like entrance area with warm light creating atmospheric sunsets; above it video waterfalls on a 360

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panorama. The centrepiece on the third floor was a water-light sculpture, a 50-metre tall light cone with water running down its sides. The dark surroundings ofthe cone shone in a cold glow, reminiscent ofthe northern lights. They transformed into various whitish-blue coloured light scenarios to culminate in a brightly glowing crystal. Three types oflight alternated: a star-shaped area of fluorescent lamps shining from the inside made the cone appear transparent. As these were dimmed and the spots on the outside around it started up, the cone became solid - as if it were covered in a matte metal material. Also, the underwater luminaires generated a picture ofmoving light reflections. The transitions between the different light scenarios were the most spectacular.

Section through the gasometer in Oberhausen showing three exhibition levels: ground floor: history of water, first floor: film installations, second floor: shining water cone with starry sky

123 Completed Schemes: Temporary Light Installa tion

Urban District: Zurich Affoltern

Light culms for a new identity

Plan Lumiere is the title ofthe lighting masterplan for the city of Zurich. It will, in future, furnish the entire area of the Swiss city with a new lighting concept. Presently it is being put into practice in smaller sub-projects. One ofthese is the district ofAffoltern, located within the catchment area of Zurich. The former village Affoltern has lost some its character in recent years with the construction ofnew building developments. The light scheme helps in providing the area with a new identity by enhancing its public spaces with light. New lighting has been especially created for pedestrians and cyclists in the area around the railway station. But also further afield new lights appear. Low light poles ofa height offour metres illuminate squares, streets and entrance points within the district. These include gateways, entrances to underpasses and the shopping centre. The luminaires break the monotony ofthe main roads and help to create a pleasant environment. Light points at ground level lead into the neighbourhoods, their numbers increase at junctions. Selective spots direct attention to special situations, give identity and atmosphere. Pedestrian areas have even lower poles with a mounting height of three metres and wide spacing. They produce a warm and calm light ambience. Additionally, light points on tall buildings highlight distinct details characteristic of the local neighbourhoods. These facilitate orientation and recognition from a long way away, and further promote the specific identity of the district. Changing light scenarios on traffic structures, such as ramps and underpasses, serve the same purpose. Light picks out new meeting places. For example, the building facade opposite the station could be used for projections to be viewed by passengers on the platforms.

Aerial view of Zurich Affoltern showing the viewpoints of the photographic survey

124

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125 Completed Schemes: Urban District

The environment ofAffoltern is marked by its heterogeneity. Congested and busy areas alternate with romantic corners. The lighting design attempts to respond to this diversity with a surprise. The luminaires are, in their original form, not usually specified for use "on land". They typically mark out waterways. LEDlamps are fitted in the luminaires' heads and run on solar powered storage batteries. They do not require conventionally generated power, neither in summer nor in winter. This feature, and its related design quality, is typical of the scheme and amazingly up to date. The luminaires are constructed from a conventional pole and a fibreglass rod at the tip ofwhich the lamp is fixed at a height ofseven metres. This makes the luminaire virtually vandal proof. It is easy and economical to erect since no power supply is required. Photovoltaic cells on the projecting "leaf' at the top of the steel pole supply the necessary power to (recyclable) storage batteries. Streetlights are generally static in appearance. In Affoltern, the light markers on the fibreglass rods move in the breeze. They sway to and fro like reeds in water, where these luminaires usually would be found. But here they are a poetic allusion to the rural environs of the village. The luminaires can tilt approximately one metre in each direction; the rod cannot turn any further, but will not break. In Europe, this suggests bamboo and thus the luminaires were named "light culms". They are painted the colour of the local grasses and are ofa slender and miniature-like appearance that only modern materials can conjure up in such a stunning manner. A true surprise on all fronts.

126

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The persuasive argument for the light culms was that they receive power from photovoltaic units on the "leaves" and storage batteries, making them independent of electric power supply.

127 Completed Schemes: Urban District

Small Town: Lemgo

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The inner city ofLemgo in North Rhine-Westphalia has an historical-contemporary ambience. Stone and timber-frame buildings dating back to the Late Gothic and Renaissance periods alternate with exemplary modern architecture. The street pattern, squares and prominent buildings determine the appearance of the former Hanseatic town. Naturally, the design concept for an integrated and artistically conceived lighting scheme should emphasise the qualitative characteristics ofthe town centre. Five zones are ofspecial relevance: - The axes at right angles to the pedestrian zone, or rather the main shopping street aligned with the town gates. - The large sections of the existing ramparts that surround the town centre, now as a public park. - The public squares, two ofthese are located close to the point ofintersection ofthe main axes. - The historical towers which serve as eye-catching points of orientation, even from a distance. - The former town gates, important routes into the town centre.

In the pilot project on Waisenhausplatz. light emitted by facades of public buildings plays a major role.

129 Completed Schemes: Small Town

The masterplan allocates individual light ambiences and moods to the five areas, all ofwhich integrate into an harmonious, coherent overall scheme. In the shopping areas, for instance, low light directed onto the ground from a height ofthree metres determines the general light effect. An important factor is the lighting ofshop windows which was coordinated with public lighting . Subtle light on the surrounding historical facades displays refined and rich detail; light from the side alleys marks vibrant points along the main axis. Even lower than in the shopping area are the light levels on the ramparts, illuminating special places. Here, darkness is preserved as a qualitative space in its own right while light on trees or groups ofplanting makes it safe to use the park. Furthermore, prominent buildings, like towers or town gates are emphasised and made easily recognisable. They are not brightly lit, but instead receive subtle , inviting light that provides balanced points of orientation. Two large squares hold great significance for the public life ofLemgo, the Marktplatz and the Waisenhausplatz. Their central location matches the vibrancy ofthe place. Public transport routes run in all directions from here. The market square especially is a success in terms ofaesthetic design. Not only due to the juxtaposition and blending ofhistorical and modern architecture, the balance ofold and new, but also due to footpath links and the composition The pink facade of Gesanghaus

ofbuildings and spaces in the overall appearance of the square. Consequentially, the lighting concept attempts to underline existing spaces in their complexity rather than isolating them as single elements. On a small scale, the complexity ofthe square is exemplified by the detail of the adjacent Town Hall; its facade turned out differently from the main body of the building because it was constructed in different phases over a long period oftime. The light attempts to carefully respond to these subtleties. From close up it is soft on the surface, subtly emphasising the quality of the architecture instead oftraining a flattening beam onto it. In addition, some small, aesthetically attractive windows are lit in the interior using minimal high-efficiency lighting in adjoining rooms. On the opposite side ofthe square, the windows of homes are lit, their lights seem to go on and off at random. Another public building, the Ballhaus, is only illuminated to show the charming architectural detail of the facade. Incidental light shining beyond the facade is blocked. All functional lighting is reduced to the lowest possible level to minimise interference with the sense of space. The surface ofMarktplatz receives different accents emitted from spotlights on poles; each of the light points is mounted at a different height. The sole exception is a water feature in the centre of the square that replaces the former historical fountain. The interplay oflight gives the square an animated appearance and increases its attraction. An axis extends across Kramerstrafse, from Marktplatz to nearby Waisenhausplatz. Here, the light ambience is similar to that ofMarktplatz, only the

130

functional lighting recedes further into the background in favour offacade lighting and shop windows. One selective light on the back elevation ofBallhaus, and the windows ofseveral public buildings lit from within lend the space an intimate atmosphere. Waisenhausplatz has two further features: firstly, a direct relationship with the market square is set up owing to an attractive view ofthe church spires. Secondly, at twilight the bus stops on Waisenhausplatz generate an animated play oflight, their roofs are transformed into light objects. Transparent glazed areas that seem to be randomly scattered across the square are pleasant to behold; they appear like immaterial luminous rectangles. The option ofchanging the colour ofthe light fed into the glazed roofs should be carefully and sparingly handled.

131 Completed Schemes: Small Town

Large City: Bremen

Light music

The face ofa city changes in the course ofnight and day. The warm, red autumn sun almost makes its facades glow, the clear winter air lets a row ofbuildings appear more three-dimensional than in damp, misty weather conditions that seem to mould shades ofgrey. This is reversed at night: windows shine to the outside, the public realm extends into houses, illuminated advertising panels compete with one another, and the lighting on streets and paths provides order and orientation. The evening and night-time appearance of the city significantly contributes to the degree in which citizens and visitors feel comfortable and like to go out.

People bring life to the city, visit the centre and identify with the place, but only if pertinent criteria are fulfilled. The 0 bjective ofthe lighting masterplan was to present the qualities of Bremen's inner city in the proper light, to place accents, introduce structure, facilitate orientation, create change and order and, in doing so, provide a pleasant atmosphere that typifies Bremen. The concept presents an integrated approach to the lighting design ofBremen's inner city. Prior to implementation of the proposed principles, it was important and also necessary to reach a detailed agreement between the involved parties. The scheme retained its message and put into practice its desired effect, even though some aspects ofthe proposals could not be realised (for example, lighting windows from the interior). In the first instance, the principles of the masterplan should be pursued to the greatest possible extent. Sightlines

A walk through the city centre of Bremen presents the visitor with a wide range of beautiful, historical buildings. The lighting scheme builds on the great density ofsignificant facades and, by lighting specific viewpoints, guides people from one site to the next. Firstly, this is accomplished by the broad lighting offascinating gables and facades and secondly, by providing smaller-scale illumination for central buildings, such as the church Liebfrauenkirche, the Cathedral and the Town Hall. Light guides the visitor through the streets and onto small, intimate squares, like that around Liebfrauenkirche for instance, and reinforces the unique charm of Bremen's city centre. Each street and each square opens out onto adjacent squares and streets, the city centre is perceived as one entity. Streets

The street spaces in the city centre can be divided into three categories: pedestrian areas, pedestrian streets with delivery access and streets predominantly for motor vehicles. Each ofthese categories has a different focus and is designed accordingly. Light poles for a mounting height offour metres illuminate the pedestrian areas, such as Stintbrucke and GrofSeWagenstrafSe as well as Kleine Wagenstrafse. This height creates a pleasant and clear atmosphere in the street - good visibility

132

Site plan of the city centre of Bremen showing all elevations on which light is applied to form spatial boundaries or which define the character of a street

Bremen was the first city to consistently plan "functional" and "design" lighting. Conflicting light effects do not occur and costs can be kept to a minimum.

133 Completed Schemes: Large City

of the light sources with the regular spacing ofpoles make it easy for pedestrians to judge distances. Hakenstrafse receives overhead wiring at a height ofeight metres because this best suits the function of the street. Light poles along one side ofthe street serve the mixed areas, like LangenstrafSe, SandstrafSe and MuseumstrafSe. In addition, important and architecturally interesting buildings are flood lit.The street space widens towards the top and presents new focal points that catch the eye ofpassers-by. The areas ofMarktstrafSe and WachtstrafSe receive overhead wiring at a height ofeight metres as they are mainly used for vehicular traffic. The light points trace the alignment ofthe road and facilitate orientation. Here, too, light picks out several important and architecturally relevant buildings and creates an interesting urban environment. Squares

There are two types ofsquare in Bremen's city centre. Firstly, the large squares with vehicular traffic, and secondly, smaller squares for pedestrian use only. Tall masts with mounting heights of9.S metres provide direct light for the large squares, like Domhof, Domsheide and Am Dom. Spots fixed to these masts cast light onto surrounding facades and objects in the square. Unlike the low lighting points used in the streets, the illumination from a height lends these squares a generous character; it makes the space appear extensive. Spots mounted at the top offacades provide light on the small-scale squares around the Town Hall and Liebfrauenkirche. The light sources are not in the pedestrians' field ofvision, but cones oflight distribute a uniform brightness over the area. To create a transition between bright street lighting on ObernstrafSeand the small squares and narrow streets, illuminance levels are staggered in different zones. This permits the wash oflight and light emitted by luminaires mounted close to the Town Hall and Liebfrauenkirche elevations to occupy the foreground, as intended. Selective spots provide soft light for Markus Fountain and the sculpture of the Town Band of Bremen. Facades

The vertical planes offacades make a significant contribution to the sense of space in squares and streets. Two complementing light principles are applied: the broad, calm light from a distant light pole or from opposite houses and the small-scale accentuated illumination ofcornices and projections on the facade itself. In combination both these principles make the facade appear generous and at the same time three-dimensional and structured. Town Hall The Town Hall, located in the city centre, displays its facade in all directions. The elevation facing the market, seen from the middle-distance, receives a wash oflight: light mounted close to the facade directed onto ornaments and figures, light on the gables and on the arcades. The roofis of the copper-green The Town Band of Bremen next to the Town Hall at the entrance to the small

variety that looks bright. Illuminated windows lend the Town Hall an animated appearance. On the elevation facing Obernstrafse, identical principles apply, in

Schoppensteel area, which is kept rather dark.

134

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135 Completed Schemes: Large City

luminosity is the response to the relatively bright shopping street. Towards Schoppensteel, the light is adjusted to suit the small scale ofthe space. It is more reserved and transforms the formerly dark area into a pleasant environment. Directed light places special emphasis on the small stairwell-tower and the Town Band of Bremen; they are the dominant features on this side of the Town Hall. The bright windows and the illuminated roofare intended to be viewed from distant Domhof. The same principles as for the other building elevations apply to the elevation facing Domhofand the back of the Town Hall. Bright windows and light on several figures (Windsbraut, for example) structure the facade and display it. Here also, a wash oflight and light on the gables bring out the distant effect. The Glocke

The austere gable elevation with its doorway arches is the central feature of the lighting scheme. A soft wash complements the lights mounted close to the facade, aligned along the vertical direction of the gable. Smaller spots light the entrance, the windows shine from within. The roofs receive a wash oflight emitted from the cornices and the back of the stairwell gables. Facade of Bremen's Tow n Hall : We found

places to mount luminaires on the roof, balconies and beneath the arcades. Not

Liebfrauenkirche

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dows (especially on the entrance elevation) and it is constructed oflarge boulders , making it appear more solid. Spots mounted on a mast erected between the trees light the walls. The existing overhead wires were removed. The rose window shines from the inside, just like the lateral windows. The tiled roofis not lit , it only reflects the stray light ofthe urban surroundings. The green roof of the tower appears like a sign of the church. The gables and recessed windows receive light from fluorescent luminaires that give depth to the facade. Cathedral

The Cathedral with its many copper roofs and two widely visible towers dominates the city centre from many viewpoints. The roofs are lit. The lights on the inside of the Cathedral windows and the facade illumination present a distinct character. The entrance portal receives direct light to bring out the shine of the gilding above the doors. Spots mounted on poles in the courtyard, Domhof, illuminate the historical building and its side entrance. The wash oflight on the front of the Cathedral makes it widely visible and emphasises the power of the church. Large-format projections on facades: building facades may serve as screens for projections of all kinds ofmotifs from large-format projectors (Pani, for example). Buildings are thus visually transformed into entirely different structures. Projectors can be temporarily fixed to opposite buildings, or to poles. Coloured light on facades: coloured light on facades completely changes their appearance and effect. Coloured architectural spotlights may be temporarily fixed to opposite buildings, to poles or mounted on the building to be lit. An additional option would be to adapt existing lighting systems (for example, floodligh ts) by inserting colour filters.

136

Laser light show

Laser light sh ows are events for special occasion s. With the use oflaser lights squares and streets may be transformed into theatrical settings. Moving lights: "intelligent" spotlights, so-called "moving lights", open many design pos sibilities. Spotlights may project moving coloured beams or gobos onto facades and the ground. Th ese systems can be installed on buildings and on masts.

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137 Completed Schemes: Large City

Large City: Luxembourg

Distinguished light management for a special flair

The topography ofLuxembourg is impressive: steep cliffs heightened with battlements, deep river valleys, winding roads and gigantic bridges, views across the valley onto the mountain ridge opposite along with the view onto the roofs of a neighbourhood 70 metres below - all this offers picturesque charm. The town, expanded throughout history, and in which important European institutions are based, is open to citizens and guests. The layout ofstreets and squares has a special Luxembourg flavour offering a high quality oflife. The aim of the lighting masterplan is to strengthen these characteristics. Blessed with sunshine and warmth, the people ofLuxembourg make the most of their public spaces: restaurants and cafes enliven the squares, people go for walks in the parks, but also use them to sit, play and have picnics.

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