Science Museum Group Journal Light as material/lighting as practice: urban lighting and energy Journal ISSN number: 2054-5770 This article was written by Joanne Entwistle, Don Slater 01-10-2018 Cite as 10.15180; 180906 Discussion Light as material/lighting as practice: urban lighting and energy Published in Spring 2018, The Material Culture of Energy Article DOI: http://dx.doi.org/10.15180/180906 Keywords Light, lighting, public realm lighting, urban design Introduction Light is a messy material that spills, bleeds and interchanges promiscuously with adjacent materials and spaces, often uncontrollably and in ways that constantly escape planning and design. Artificial urban lighting, the focus of our attention, is the by-product of many other practices, which it reflects and extends into a social space: public light may arise from the headlights of cars, people switching on domestic lights, the glow of televisions, or civic infrastructural provision. Whereas urban lighting planning and regulation attempts to forecast the energy consumption of public realm lighting on a technical basis (and both cities and manufacturers attempt to implement new LED and digital control technologies on the basis of a reductive technological rationality), this article will use material from Configuring Light research on public realm lighting to argue that deciphering energy consumption really does require equal attention to the material properties of light and the interlinked practices through which social spaces come to be lit. Our argument addresses these connections between materiality and practice. As a material, light has properties: it is a social material we all configure in everyday life and routine practices. In our homes we use overhead lights, lamps, possibly candles, etc., while lighting designers’ practices draw on many tools and techniques to light public spaces. However, the materiality of light is often lost because light is quite abstract and, unless we are lighting professionals, we often fail to recognise or understand its materiality, or simply not reflect on it. Indeed, despite its pervasive presence, light is perversely invisible: we just flick a switch. Understanding material and social lighting practices in an urban context is complicated by two dominant regimes for acting on light that tend to be split off. On the one hand, light is routinely treated as a purely technical matter, as an economic and
Transcript
Science Museum Group Journal
Light as material/lighting as practice: urban lighting and energyJourna l ISSN numbe r: 2054-5770
Thi s a rti cl e wa s wri tte n by Joa nne Entwi s tl e , Don Sl a te r
01-10-2018 Ci te a s 10.15180; 180906 Di s cus s i on
Li ght a s ma te ri a l /l i ghti ng a s pra cti ce : urba n l i ghti ng a nd e ne rgy
Publ i s he d i n Spri ng 2018, The Ma te ri a l Cul ture of Ene rgy
Arti cl e DOI: http://dx.doi .org/10.15180/180906
Keywords
Light, l ighting, publ ic realm l ighting, urban des ign
Introduction
Light is a messy materia l that spi l l s , bleeds and interchanges promiscuously with adjacent materia ls and spaces, often
uncontrol lably and in ways that constantly escape planning and des ign. Arti ficia l urban l ighting, the focus of our attention, i s
the by-product of many other practices , which i t reflects and extends into a socia l space: publ ic l ight may arise from the
headl ights of cars , people switching on domestic l ights , the glow of televis ions, or civic infrastructural provis ion. Whereas
urban l ighting planning and regulation attempts to forecast the energy consumption of publ ic realm l ighting on a technical
bas is (and both ci ties and manufacturers attempt to implement new LED and digi ta l control technologies on the bas is of a
reductive technological rational i ty), this article wi l l use materia l from Configuring Light research on publ ic realm l ighting to
argue that deciphering energy consumption real ly does require equal attention to the material properties of light and the
interl inked practices through which socia l spaces come to be l i t.
Our argument addresses these connections between materia l i ty and practice. As a materia l , l ight has properties : i t i s a socia l
materia l we al l configure in everyday l i fe and routine practices . In our homes we use overhead l ights , lamps, poss ibly candles ,
etc., whi le l ighting des igners ’ practices draw on many tools and techniques to l ight publ ic spaces. However, the materia l i ty of
l ight i s often lost because l ight i s quite abstract and, unless we are l ighting profess ionals , we often fa i l to recognise or
understand i ts materia l i ty, or s imply not reflect on i t. Indeed, despite i ts pervas ive presence, l ight i s perversely invis ible: we
just fl ick a switch.
Understanding materia l and socia l l ighting practices in an urban context i s compl icated by two dominant regimes for acting on
l ight that tend to be spl i t off. On the one hand, l ight i s routinely treated as a purely technical matter, as an economic and
environmental cost that i s subject to purely materia l calculation in terms of measurable quanti ties of l ight at a speci fic cost
per unit. This approach is encapsulated in the idea of standards: standards schematise socia l practices and spaces into
conventional forms for which minimum l ighting levels can be recommended (Busch, 2011). These standards are then
introduced, uni formly, in myriad settings as i f they were scienti fic and universal , often ignoring the many di fferent forms of
socia l l i fe in which they are implemented. Indeed, some of the blandness of l ighting in many ci ty streets and publ ic spaces (ugly
masts , too bright and flat l ighting, for examples) comes down to this tendency to impose a s ingle standard of l ighting on to
spaces uni formly, regardless of the variations of socia l l i fe that might actual ly characterise these spaces or streets . For
example, a pedestrianised shopping street in a ci ty l ike Derby (see our study, Entwistle et a l , 2015) does not have to be blasted
with l ight ramped up to ‘motorway standards’ from inhumanly ta l l masts in order to make the space safe and secure; i t i s
normal ly more effective to attend to the ways in which speci fic types of socia l actors use and interact in this space and how
l ighting can support their practices .
On the other hand, and conversely, especial ly in ci ty branding and place marketing practices within and without municipal
governance, l ight i s routinely and increas ingly treated as an aesthetic matter. Place-marketing strategies of this i lk tend to
reduce the materia l properties of l ight to sensuous imagery, ‘to-be-photographed’ spaces for ci ty brochures. As cri tiqued by
Jul ier (2005) these images display a fami l iar concern with architectural form and ‘landmark bui ldings ’ found in many s imi lar
place branding materia ls . As Lee (2014) argues, drawing on Taylor (1988), the emergence of the skyl ine as a favoured
perspective in nineteenth-century New York has to do with how people began to approach the ci ty by rai l and road. General ly,
then, this imagery is concerned with the ci ty from a distance, a photogenic perspective, ‘as seen from Marina Bay’, or from any
of the high-rise hotels , condominiums and office towers skirting the ci ty. This distinct perspective is meant to be both
experienced and photographed, a memorable ‘image of the ci ty...’ (Lee, 2014, p 147).
The potentia l of l ight as ‘affective’ materia l cannot be denied (Edensor, 2012; 2017) and is one reason why l ight festivals – such
as Glow in Eindhoven, Fête des Lumières in Lyon and Vivid in Sidney – are prol i ferating around the globe. Yet the problem here is
that the materia l properties of l ight are reduced to representations that standardise the ci ty or place identi ty, and are often
treated as part of spectacular display rather than everyday practice: l ighting is once again separated from the actual socia l
practices of diverse people who use that place.
This dual i ty – l ight i s ei ther a technical or aesthetic matter – divorces l ighting and i ts energy costs from socia l practices .
General ly, l ighting immediately becomes an economic and technical equation to be solved within a functional ist and
technocratic framework. This tendency is increas ing with the technological shi ft towards LED and ‘smart’ l ighting systems. For
example, municipal i ties widely ci te energy cost savings of up to 85 per cent (eg, The Cl imate Group, 2012) to be achieved by
implementing LED streetl ighting, projections that are based mainly on the cost per lumen technical ly required to produce the
same l ight levels as older technologies . This ignores the actual socia l patterns of energy demand, some of which are generated
by the technology i tsel f. There is a healthy, i f as yet unresolved, debate about the ‘rebound effect’, for example, whereby the very
cheapness of LED running costs leads ci ties to instal l far more and far brighter l ights than required, thereby squandering the
energy gains made on a purely technical bas is (Tsao & Waide, 2010; Jenkins et a l , 2011; Schleich et a l , 2014; Winther & Wi lhite,
2015) (see also http://advances.sciencemag.org/content/3/11/e1701528). Lighting des igners (in our research), as opposed to
planners and engineers , tend to be sceptical about gains over older technologies , particularly s ince their focus is on the lowest
l ight levels needed to support socia l practices . Indeed, l ighting des igners have a host of strategies for l ighting in energy efficient
and aesthetic ways that cut across the dominant schism by vi rtue of an understanding of the special materia l of l ight and what
i t can do in socia l space. In other words, what we have found is that energy and economic cost i s actual ly a l l too vis ible, even
obsess ive, in l ighting planning; what gets obscured are the socia l i ssues and the ways des igners can des ign with the socia l in
mind. Our research would suggest that debates about energy tend to result in technocratic ‘solutions’ that miss out the
fundamental point of a l l energy use and consumption: how i t i s practiced, socia l ly embedded and used. Therefore, to unpack al l
this we need to examine precisely what sort of materia l l ight i s and also what we mean by ‘socia l practices ’.
Fi rstly, l ight i s a relational materia l . We do not perceive l ight directly but only in the ways i t interacts with other materia ls and
surfaces – by reflecting, colouring, texturing, shadowing and so on. To even begin to calculate what levels of l ighting and energy
are des ired, the des igner has to cons ider the workings and interactions of a l l the materia l surfaces in a space as they are
assembled through diverse and overlapping practices .
Secondly, l ight has a fluid qual i ty that makes i t di fficult to control , and which makes the very idea of l ighting des ign and
planning a bi t of a fiction. Lights spi l l s and bleeds outs ide of i ts intended area, flooding adjacent spaces, overlapping with
neighbouring des igns and schemes. Light wreaks havoc with the idea of a l ighting master plan, which is eas i ly disrupted by a
shop’s bright s ignage or a pass ing car, or other planning decis ions taken, as happened in our study of the l ighting masterplan
of Derby ci ty centre. The same day the l ighting des igners del ivered their master plan to the Counci l they were told that the
Marketing Derby office were about to instal l huge LED screens a long the ring road around the ci ty centre which would bleed out
vast levels of l ight, undermining their careful l ighting plan. This bleeding plays a s igni ficant part in the ratcheting up of l ight
levels in ci ties : an over-l i t area casts adjacent spaces into comparative darkness , making them feel too dark and thus ‘unsafe’,
and putting pressure to increase their l ighting in order to compete. In energy terms, this l ighting ‘arms race’ i s clearly
unsustainable, as wel l as detrimental to human and animal wel l -being.
Thirdly, the relational and fluid qual i ties of l ight are compounded by the fact that most l ighting arises as a by-product of socia l
practices which are not intended as ‘des ign’ or ‘planning’: people switch on l ights to do stuff in their homes, i l luminating the
street outs ide, whi le car headl ights and street and shop s ignage are part and parcel of the mix of private and publ ic socia l
practices with l ight that combine in myriad ways with the practices of counci ls and planners in their streetl ighting and safety
regulation. More than s imply disrupting plans and des igns, we’ve come to think of a l l this l ighting as related in an ‘indexical ’
way to the practices that give rise to them: the l ighting that makes up a scene arises as a by-product of practices which i t
supports , whi le at the same time structuring the relationship between that practice and adjacent ones.
Fourthly, i f l ighting is relational , fluid and indexical , then i t i s more l ike a temporal event than l ike a materia l s tructure, and
l ighting des igners use a language that i s often quite theatrical : l ighting involves narrative, pathways, scenes, trans itions and so
on. Lighting des igners , as opposed to, say, architects , understand space as emergent: a space is l i t in terms of complex and
largely uncontrol lable relations between many di fferent materia ls , spatia l zones and socia l practices that rely on, and often
produce, l ight. Des igners general ly ta lk about ensuring that a space ‘works ’, that the l ighting should make the space navigable,
legible, convivia l , safe and so on. This a lso tends to focus attention squarely on what people are trying to do in a space, and the
confl icting things they may be up to, and giving a materia l order or cultural form to the space in which those practices are
carried out.
What does a l l this mean for energy consumption? It i s notable that every l ighting des igner we’ve worked with has not only been
committed to instal l ing less light and working with more darkness but routinely characterised their relationship with cl ients as
a struggle to ‘l ight less but more intel l igently’. We take this to mean that a lower energy approach to publ ic l ighting needs to
work not only through the socia l practices i t i s meant to sustain, rather than hiding the socia l behind the technical or aesthetic;
i t must a lso work through a knowledge of the materia l properties of l ight as they are understood by des igners to structure a
socia l space. Lighting des igners have at their disposal a range of techniques and strategies that involve lowering the l ight
levels , l ighting strategical ly to mark out socia l ly s igni ficant features in a space (a tree, a statue, and so on), to increase
legibi l i ty and navigabi l i ty of that space in ways that make i t feel safer and more secure. Such l ighting is des igned for the space,
much l ike a stage des ign, as opposed to a technical ly engineered l ighting solution of whacking up a bright l ight, as i s so often
the case when publ ic l ighting is merely engineered. Contrast the two pictures of Museum Square in Derby (see Figures 1 and 2).
The top image demonstrates the ‘motorway l ighting’ discussed above, a large, bright overhead mast blasting down bright l ight
and casting the surrounding areas in relative darkness , making the space i l legible. The picture below is an image of the l ighting
des igners Speirs+Major’s publ ic mock-up for the ci ty counci l and publ ic, showing how the square could be l i t with the same
lux/l ighting level but in a more even and socia l ly meaningful way that picks out the features in the space and therefore make i t
more legible and navigable: both l ighting scenes involve the same energy cost.
