Global Approaches to Reduce Light Pollution from Media Architecture and Non-Static, Self-Luminous LED Displays for Mixed-Use Urban Developments

Article (PDF Available)inSustainability 11(12):3446 · June 2019with 95 Reads
DOI: 10.3390/su11123446
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Abstract
Urban environments have become significantly brighter and more illuminated, and cities now consider media architecture and non-static, self-luminous LED displays an essential element of their strategy to attract residents, visitors, and tourists in the hours after dark. Unfortunately, most often, they are not designed with care, consideration, and awareness, nor do they support the visual wellbeing and circadian rhythms of humans. They also increase light pollution which has an adverse effect on the environment. The aim of this study was to estimate the scale of the negative impact of 28 non-static, self-luminous LED shop window displays within a real-life city context along the main shopping street Banhofstrasse in Zurich, Switzerland. An experimental field measurement survey investigation was performed to identify visual luminance with commonly available tools such as a luminance meter and a digital reflex camera for luminance photography. Moreover, the most important global approaches to reduce light pollution were evaluated in the form of existing guidelines, technical standards, and laws, all of which should be considered when specifying illuminated digital advertisements. A literature review and survey results both confirmed the extent of the problem and highlighted, too, the need to better measure, apply, and manage this new technology. The authors' proposal for improvements involve practical recommendations for the design and implementation of future projects which can positively guide and direct this growing trend.
sustainability
Article
Global Approaches to Reduce Light Pollution from
Media Architecture and Non-Static, Self-Luminous
LED Displays for Mixed-Use Urban Developments
Karolina M. Zielinska-Dabkowska 1, * and Kyra Xavia 2
1GUT Light Lab, Faculty of Architecture, Gdansk University of Technology (GUT), 80-233 Gdansk, Poland
2International Dark-Sky Association, Tucson, AZ 85719, USA; kyra.xavia@darksky.org
*Correspondence: k.zielinska-dabkowska@pg.edu.pl; Tel.: +48-583-472-315
Received: 1 April 2019; Accepted: 18 June 2019; Published: 22 June 2019


Abstract:
Urban environments have become significantly brighter and more illuminated, and cities
now consider media architecture and non-static, self-luminous LED displays an essential element
of their strategy to attract residents, visitors, and tourists in the hours after dark. Unfortunately,
most often, they are not designed with care, consideration, and awareness, nor do they support
the visual wellbeing and circadian rhythms of humans. They also increase light pollution which
has an adverse eect on the environment. The aim of this study was to estimate the scale of the
negative impact of 28 non-static, self-luminous LED shop window displays within a real-life city
context along the main shopping street Banhofstrasse in Zurich, Switzerland. An experimental field
measurement survey investigation was performed to identify visual luminance with commonly
available tools such as a luminance meter and a digital reflex camera for luminance photography.
Moreover, the most important global approaches to reduce light pollution were evaluated in the
form of existing guidelines, technical standards, and laws, all of which should be considered when
specifying illuminated digital advertisements. A literature review and survey results both confirmed
the extent of the problem and highlighted, too, the need to better measure, apply, and manage
this new technology. The authors’ proposal for improvements involve practical recommendations
for the design and implementation of future projects which can positively guide and direct this
growing trend.
Keywords:
light pollution; media architecture; media facades; non-static LED displays; LED screens;
illuminated digital advertisement; video displays; self-luminous surfaces
1. Introduction
In recent decades, urban environments have become significantly brighter and more illuminated
(Figure 1), and cities now consider lighting an essential element of their strategy to attract residents,
visitors, and tourists in the hours after dark [
1
,
2
]. Additionally, urban planners have realized that
dividing a city into separate districts for specific purposes, such as residential, commercial, cultural,
institutional or environmental land use, no longer works from a functional perspective for city
inhabitants. After business hours, one can observe that in commercial and institutional quarters,
these parts of a city can become dark and unwelcoming places with an absence of people in the
streets. To overcome this problem and inject more life into certain city areas, a new trend has emerged.
Mixed-use development integrates retail (i.e., shops and restaurants) enterprises which are often
located on the ground floor, with commercial and residential properties on the floors above. While
this change increases economic prosperity and socializing in the night hours to create livable cities [
3
],
increased light pollution can negatively impact the area and reduce the quality of life for residents [
4
,
5
].
Sustainability 2019,11, 3446; doi:10.3390/su11123446 www.mdpi.com/journal/sustainability
Sustainability 2019,11, 3446 2 of 33
Sustainability 2019, 11, x FOR PEER REVIEW 2 of 34
Figure 1. Guangzhou, China: cities now consider creative lighting an essential element of their
strategy to attract residents, visitors, and tourists in the hours after dark. Source: Signify’s figure.
In 2009, an approved European 2020 Strategy for climate change and energy recommended the
following: minimizing greenhouse gas emissions to 20% lower than 1990 levels, the use of 20% of
energy coming from renewable sources, and a 20% increase in energy efficiency that involves the
employment of effective technologies such as LEDs [6].
As LED lighting is considered more energy efficient, adaptable, and cheaper to operate than
older light sources, it is already in use in street lighting retrofit projects [7–9], historical urban settings
[10], facade illumination [11,12], landscape lighting [13], in trials for a smart city [14], and as animated
LED video advertisement displays in different forms applied to buildings [15]. According to market
estimates and forecasts, the future trend of global LED video display technology will grow around
35% over the next decade, reaching approximately $73 billion by 2025 [16]. Certainly, when applied
and controlled properly with suitable relevance to the building’s architecture and/or the urban realm
in which they are introduced, media architecture and non-static, self-luminous LED displays can
positively add to the nighttime image of a city by creating a visually stimulating atmosphere [17]. But
adequate guidance is necessary and one should acknowledge not all cities and towns need visual
clutter. Times Square, Piccadilly Circus, and Shinjuku each have their own historical relationship
with bold advertisements that create a one-of-a-kind place of identity that attracts tourists, but it is
worth noting that these areas do not contain residential dwellings (city accommodations should
provide adequate darkness at night for the health and wellbeing of its inhabitants).
Researchers and practitioners within the field have provided some insights into the body of
knowledge of these new urban elements, from technology and prototyping [18], policy and design
issues [19,20], social interaction [21], displayed context [22], to design challenges [23], aesthetics [24],
and more. Alas, there is still very little research on the environmental and health impacts of outdoor
media architecture [25]. Therefore, while research exists to assist our understanding of this trend and
its numerous applications, more studies are required to help better apply and manage the use of this
recently developed lighting technology.
This is pertinent because the majority of non-static, self-luminous LED displays today are
excessively bright and without any controls in place [26,27]. This diminishes the nighttime landscape
here on Earth, whilst also substantially adding to the sky glow above cities. Light pollution, also
known as obstructive light, prevents astronomical observations and disconnects humanity from the
night sky as well [28]. In particular, LEDs emit excessive luminance and generate unwanted glare
[29]. Also, their high-intensity light restricts the pupil in the human eye, thus dark adaptation is
prevented, making it impossible to detect all but the brightest stars in the sky (while the sky may
appear almost black, the fine detail of the night sky becomes invisible) [30,31].
Figure 1.
Guangzhou, China: cities now consider creative lighting an essential element of their strategy
to attract residents, visitors, and tourists in the hours after dark. Source: Signify’s figure.
In 2009, an approved European 2020 Strategy for climate change and energy recommended the
following: minimizing greenhouse gas emissions to 20% lower than 1990 levels, the use of 20% of
energy coming from renewable sources, and a 20% increase in energy eciency that involves the
employment of eective technologies such as LEDs [6].
As LED lighting is considered more energy ecient, adaptable, and cheaper to operate than older
light sources, it is already in use in street lighting retrofit projects [
7
9
], historical urban settings [
10
],
facade illumination [
11
,
12
], landscape lighting [
13
], in trials for a smart city [
14
], and as animated
LED video advertisement displays in dierent forms applied to buildings [
15
]. According to market
estimates and forecasts, the future trend of global LED video display technology will grow around
35% over the next decade, reaching approximately $73 billion by 2025 [
16
]. Certainly, when applied
and controlled properly with suitable relevance to the building’s architecture and/or the urban realm
in which they are introduced, media architecture and non-static, self-luminous LED displays can
positively add to the nighttime image of a city by creating a visually stimulating atmosphere [
17
].
But adequate guidance is necessary and one should acknowledge not all cities and towns need visual
clutter. Times Square, Piccadilly Circus, and Shinjuku each have their own historical relationship with
bold advertisements that create a one-of-a-kind place of identity that attracts tourists, but it is worth
noting that these areas do not contain residential dwellings (city accommodations should provide
adequate darkness at night for the health and wellbeing of its inhabitants).
Researchers and practitioners within the field have provided some insights into the body of
knowledge of these new urban elements, from technology and prototyping [
18
], policy and design
issues [
19
,
20
], social interaction [
21
], displayed context [
22
], to design challenges [
23
], aesthetics [
24
],
and more. Alas, there is still very little research on the environmental and health impacts of outdoor
media architecture [
25
]. Therefore, while research exists to assist our understanding of this trend and
its numerous applications, more studies are required to help better apply and manage the use of this
recently developed lighting technology.
This is pertinent because the majority of non-static, self-luminous LED displays today are
excessively bright and without any controls in place [
26
,
27
]. This diminishes the nighttime landscape
here on Earth, whilst also substantially adding to the sky glow above cities. Light pollution, also
known as obstructive light, prevents astronomical observations and disconnects humanity from the
night sky as well [
28
]. In particular, LEDs emit excessive luminance and generate unwanted glare [
29
].
Also, their high-intensity light restricts the pupil in the human eye, thus dark adaptation is prevented,
making it impossible to detect all but the brightest stars in the sky (while the sky may appear almost
black, the fine detail of the night sky becomes invisible) [30,31].
Sustainability 2019,11, 3446 3 of 33
When such displays are visually too bright compared to the surroundings, they also negatively
impact the movement of pedestrians and drivers [
32
]. Additionally, light trespass may enter the
interior of residential properties at night, causing distress and insomnia [33].
As there are no worldwide established standards and recommendations regarding how to correctly
design, apply, and verify the impact of media architecture and colorful, non-static, self-luminous LED
displays in an urban context [
34
], research in this field seems to be novel and significant. Furthermore,
immediate action is required by the international authority on light and illumination—the International
Commission on Illumination (CIE)—to provide guidelines to reduce the impact of artificial light at
night (radiating from these lighting features) on all end users (humans, flora, and fauna), and to
encourage respect for the nighttime urban landscape, while at the same time, supporting business and
event advertising, and ensuring easy navigation and wayfinding in cities.
Ideally, there ought to be a balance between these conflicting developments. But how can
improvements be made when the approved research methodology islimited and measuring instruments
to evaluate the luminance (how bright an illuminated surface will appear) of non-static, self-luminous
LED displays are unavailable? Only recently in 2018 did the CIE establish a Technical Committee (4–58:
Obtrusive Light from Colourful and Dynamic Lighting and its Limitation) [
35
] to provide guidelines
for the implementation and usage of colorful and dynamic lighting in outdoor applications. It aims to
limit obtrusive light to allow astronomical observations, support human health, and to protect the
nighttime environment. The CIE is also now looking into the development of metrics and suitable
methods that will help to limit or prevent obtrusive light from such lighting systems.
The first aim of this research study is to raise awareness about global light pollution in mixed-use
developments in large cities from media architecture and non-static LED displays, and to provide an
in-depth account of existing global light pollution laws. With such displays becoming more common
in urban environments, this material is not only relevant and necessary, it will help shape the future
landscape and nightscape of our cities and towns.
Moreover, based on the presented case study of Zurich’s Banhofstrasse shopping street, which
has experienced an unprecedented 43 fold increase in the installation of video LED displays since 2015,
suggestions are proposed on how to improve the existing situation with guidance that contributes new
knowledge to the field. The authors also highlight the possible diculties involved with measuring
non-static, self-luminous LED displays with commonly approved and available devices such as a
luminance meter and digital reflex camera for luminance photography.
The second aim of this research study is to establish eective design principles that contribute to
the development of environmentally sustainable regulations for the design and application of non-static,
self-luminous LED advertising. It is not only lighting designers and illuminating engineers who will
gain from this research; those involved in the design, planning, and approval process will also benefit.
This includes light artists, architects, urban planners, landscape designers, sustainability consultants,
biologists, ecologists, and planning ocers (representatives of local planning authorities). Last but
not least, this research will help improve the enjoyment of cities after dark. This includes improved
walkability, navigation and wayfinding in urban spaces, and most importantly, the facilitation of
conditions that better support quality sleep for residents, tourists, and visitors alike.
This paper is organized into eight sections. Section 1: demonstrates how the research fits within a
larger field of study and highlights why it is important. Section 2: provides definitions and an extensive
background study of global approaches to reduce light pollution. Section 3: defines the research
hypothesis. Section 4: describes traditional methodologies and new methods and protocols to evaluate
the luminance of non-static, self-luminous LED displays. Section 5: provides a precise description
and summary of the experimental results. Section 6: discusses the findings and their implications,
and explains how they can be interpreted via their perspective of the working hypotheses. Section 7:
provides the study’s limitations. Finally, Section 8was added to provide a synthesis of the key points
and recommends new areas for future research, as Sections 7and 8of the study are long and complex.
Sustainability 2019,11, 3446 4 of 33
2. Background Research
An extensive background study was undertaken for a period of six months. This involved
investigating the global approaches to reduce light pollution from media architecture and animated
LED displays. Our research consisted of a thorough review of published lighting standards, guidance
and policies, books, scientific research papers, reports, and realized case studies, and also involved
personal interviews with tram drivers and passersby within in the area researched.
2.1. The Importance of Correct Definitions
When a new field emerges, as in the case of media architecture [
36
], and when no clear
interchangeable definitions are established by professionals that can be commonly adopted by
the general public, one ends up with dierent interpretations and meanings [
37
]. A definition permits
mutual understanding of a topic when a particular subject is discussed and debated. In the context of
this paper, in order to fully absorb and understand the content, definitions for the following four terms
have been provided: (1) media architecture; (2) non-static LED advertising; (3) visual light clutter; and
lastly, (4) light pollution (Table 1).
As more research and knowledge relating to the field of lighting have become available, the
definition of media architecture [38] requires an update.
Table 1. An overview of new definitions. Source: authors’ elaboration.
Definition Proposed Description
Media Architecture
Media architecture is a new emerging field within exterior illumination, where
dynamic graphics, text, images, and spatial movement are displayed on elements of
the built environment, properly integrated within architectural structures and/or
buildings within public spaces. Modern digital technologies allow for adaptation
and interaction with users. The main function of media architecture is to
“communicate specific information” in an active, dynamic, and interactive form via
high-quality visual and artistic content. Media facades and digital outdoor media
displays that emit light are a vital component of media architecture and the
digitalization of cities, forming part of the original and intellectual enrichment of
the urban environment with cultural, social, and economic implications for the
immediate surroundings. Such installations are usually permanent in nature, but
can have variable, temporary content. Well-designed media architecture should not
only enhance the environment, it should also be biologically and ecologically
responsible, minimizing its impact on the nighttime landscape, and the health and
well-being of human residents, wildlife, and/or flora and fauna.
Non-Static LED
Advertising
Non-static LED advertising can be defined as a means of promoting just about
anything in a publicly or privately owned space. It can also be used commercially
for marketing purposes (light art installations). The systems use LEDs and feature
dierent resolutions, colors, luminous intensities, and lighting controls. They can
be installed on a temporary or permanent basis, and content can be dynamic or
static, in low or high resolution, and in the form of text, images or video sequences.
Due to the technological advancements in the development of the brightness of
LEDs, such display systems can also be used outdoors during daylight hours.
There are dierent types of digital advertising platforms: signs, logos, lettering,
shop windows, screens or media facades [39].
Visual Light Clutter
Visual light clutter in the urban environment at night (Figure 3) is defined by the
authors as the state in which too many items lead to a degradation of the
performance of a visual task at night. This occurs when the human eye cannot rest,
as it is constantly scanning, moving, and absorbing information from an
environment with an excess of light sources, coupled with sudden changes in
luminance levels and contrast. All of these factors can cause an extreme sense of
chaos and disharmony in the urban realm.
Light Pollution
. . . every form of artificial light in the wrong place at the wrong time which
creates sky glow, glare, nuisance, and other relevant causes of environmental
degradation including some properties of artificial light which emit
non-environmentally friendly or inappropriate light” [
40
]. Typically, light pollution
consists of four forms: sky glow, glare, over-lighting, and light trespass.
Sustainability 2019,11, 3446 5 of 33
Today, it is also important to dierentiate between media architecture and commercial LED video
advertising, which is often inadequately integrated within a building envelope and works as an add-on.
Keep in mind that the location of media architecture is usually decided by the architect of a particular
building and other consultants in order to eliminate any potential safety conflicts in critical trac
zones, for example, intersections where the increased attention of pedestrians, cyclists, and drivers of
cars, buses, trams, and other vehicles is required. To reduce the negative impact on the environment
and the health and wellbeing of residents, appropriate design and controls are necessary.
Additionally, high-quality visual and artistic content should be provided and applied by
professional designers who also define and set dierent technical parameters. This may include
the appropriate pace (number of frames per minute) to allow enough time for identification and
absorption of the communicated message. While media architecture can become a well-known
landmark for both tourists and locals alike—it is important to stress that although media architecture
can incorporate elements of digital outdoor advertising, LED outdoor advertising is not media
architecture per se (Figure 2). Both media architecture and non-static LED display advertising can add
to visual light clutter if it is poorly designed (Figure 3).
Interestingly, with time and exposure, some people become “immune” to advertising information
and overload, and as a consequence, barely notice advertisements. This questions the overall impact
and substantial cost of such marketing modes employed in the late hours of the night.
Sustainability 2019, 11, x FOR PEER REVIEW 5 of 34
Today, it is also important to differentiate between media architecture and commercial LED
video advertising, which is often inadequately integrated within a building envelope and works as
an add-on. Keep in mind that the location of media architecture is usually decided by the architect of
a particular building and other consultants in order to eliminate any potential safety conflicts in
critical traffic zones, for example, intersections where the increased attention of pedestrians, cyclists,
and drivers of cars, buses, trams, and other vehicles is required. To reduce the negative impact on the
environment and the health and wellbeing of residents, appropriate design and controls are
necessary.
Additionally, high-quality visual and artistic content should be provided and applied by
professional designers who also define and set different technical parameters. This may include the
appropriate pace (number of frames per minute) to allow enough time for identification and
absorption of the communicated message. While media architecture can become a well-known
landmark for both tourists and locals alike—it is important to stress that although media architecture
can incorporate elements of digital outdoor advertising, LED outdoor advertising is not media
architecture per se (Figure 2). Both media architecture and non-static LED display advertising can
add to visual light clutter if it is poorly designed (Figure 3).
Figure 2. Times Square, New York, US: LED outdoor advertising is not media architecture per se.
Source: Andre Benz/Unsplash’s figure.
Figure 3. Visual light clutter of Shinjuku—one of Tokyo’s business districts at night. Source: Perati
Komson/Shutterstock’s figure
Figure 2.
Times Square, New York, US: LED outdoor advertising is not media architecture per se.
Source: Andre Benz/Unsplash’s figure.
Sustainability 2019, 11, x FOR PEER REVIEW 5 of 34
Today, it is also important to differentiate between media architecture and commercial LED
video advertising, which is often inadequately integrated within a building envelope and works as
an add-on. Keep in mind that the location of media architecture is usually decided by the architect of
a particular building and other consultants in order to eliminate any potential safety conflicts in
critical traffic zones, for example, intersections where the increased attention of pedestrians, cyclists,
and drivers of cars, buses, trams, and other vehicles is required. To reduce the negative impact on the
environment and the health and wellbeing of residents, appropriate design and controls are
necessary.
Additionally, high-quality visual and artistic content should be provided and applied by
professional designers who also define and set different technical parameters. This may include the
appropriate pace (number of frames per minute) to allow enough time for identification and
absorption of the communicated message. While media architecture can become a well-known
landmark for both tourists and locals alike—it is important to stress that although media architecture
can incorporate elements of digital outdoor advertising, LED outdoor advertising is not media
architecture per se (Figure 2). Both media architecture and non-static LED display advertising can
add to visual light clutter if it is poorly designed (Figure 3).
Figure 2. Times Square, New York, US: LED outdoor advertising is not media architecture per se.
Source: Andre Benz/Unsplash’s figure.
Figure 3. Visual light clutter of Shinjuku—one of Tokyo’s business districts at night. Source: Perati
Komson/Shutterstock’s figure
Figure 3.
Visual light clutter of Shinjuku—one of Tokyo’s business districts at night. Source: Perati
Komson/Shutterstock’s figure
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    Designing historic building floodlighting belongs to fairly complicated tasks. Apart from a purely technical imagination and adherence to floodlighting principles and methods, aesthetic aspects should also be taken into account. Predicting the effect, which will be created, is a very difficult thing. It is often impossible for us to check, owing to the dimensions of the illuminated structures, number of the used lighting equipment and its installation capabilities. Here comes 3D computer graphics. The paper presents a case study of floodlighting Palace of the Commonwealth in Warsaw, Poland. A few concepts of illuminating the palace have been described, the analysis of effects has been made and the concept that after some consultations was selected for implementation has been demonstrated. All the floodlighting designs are shown in a form of the photorealistic visualization of lighting with a description of the intended and obtained effects. Apart from the visual evaluation, the level of the building luminance was carefully monitored under the project. © 2017, LLC Editorial of Journal “Light Technik”. All rights reserved.