Abstract: Over the past decades, lighting professionals have influenced the experience of the night by brightly illuminating streets, buildings, skylines, and landscapes 24/7. When this became the accepted norm, a dual perspective on night-time was shaped and the visual enjoyment of visitors after dusk was prioritized over natural nightscapes (nocturnal landscapes). During this time, researchers of artificial light at night (ALAN) observed and reported a gradual increase in unnatural brightness and a shift in color of the night-time environment. As a consequence, ALAN has been identified as a relevant pollutant of aquatic and terrestrial habitats, and an environmental stressor, which may adversely affect a wide range of organisms, from micro-organisms to humans. Unfortunately, lighting professionals and ALAN researchers usually attempt to solve today’s sustainable urban lighting problems distinctive to their fields of study, without a dialogue between research and practice. Therefore, in order to translate research knowledge as an applicable solution for the lighting practice and to minimize the impact on the environment, a collaborative framework involving a transdisciplinary process with lighting professionals is crucial to potentially bring the practice, research, production, decision-making, and planning closer to each other. This paper presents a framework to help reduce the existing gap of knowledge, because appropriate lighting applications depend upon it. Access to less light polluted nightscapes in urban environments is just as important as access to unpolluted water, food, and air. This call for action towards sustainable urban lighting should be included in future lighting policies to solve the urgent environmental and health challenges facing our world.

Abstract: Lighting is a vital environmental element that affects people's outdoor activities and the creation of liveable neighbourhoods in cities. The use of appropriate lighting at night in public spaces can benefit people's social well-being. This research examined the effects of urban morphological characteristics on outdoor night-time lighting behaviours by analysing 11 urban neighbourhoods that reflect the variety of the prevailing urban morphological patterns in the city centres of Shenzhen. A set of urban morphological descriptors were analysed and two lighting parameters were evaluated by on-site measurement. The results revealed that the low-density high-rise modern neighbourhoods presented very high outdoor illuminance levels, but extremely low occupant use at night, and consequently, remain significant potential of light pollution and energy waste. By contrast, urban villages with high-density mid-rise patterns possess limited outdoor lighting facilities but exhibited very high nocturnal neighbourhood vitality. This type of neighbourhood presents a “demand-oriented and energy-saving” lighting behaviour during the night-time through the use of light spill from the nearby indoor light sources. Multivariable linear regression indicated that morphological characteristics significantly contribute to the illumination distribution within urban spaces. Together, building coverage ratio, floor area ratio, tree coverage ratio and ground surface albedo explain 88% of the variability of night-time site illuminance uniformity. With adding the dimension of urban morphology, this research tries to extend the scope of urban nocturnal lighting studies and provides insights into the setting of more specific criteria for urban design, so as to contribute to healthy city initiatives.

Abstract: Outdoor lighting offers many benefits to its users and is often considered a necessity for an active lifestyle when living in modern society. Sustainable outdoor lighting should fulfil the functional needs of the users, be cost- and energy-efficient, and result in minimal environmental impact. So far, a limited number of studies have been able to present clear strategies on how to plan and use outdoor lighting to ensure that it contributes towards sustainable development. Therefore, this study aimed to answer the following questions: (1) How many of the previously established sustainability indicators are already used by municipalities in their lighting planning? (2) Which types of indicators are not used by municipalities? Another aim of the study was to further develop the framework of sustainability indicators by adding new indicators that were identified from lighting plans of Swedish municipalities and the existing literature. In this study, lighting master plans from 16 randomly chosen Swedish municipalities with varying population sizes were analyzed. The results show that few sustainable indicators are used by the municipalities’ lighting plans, especially in the social dimension. The existing framework of sustainability indicators was developed by adding new indicators. Furthermore, 28 new indicators were identified, eight originated from new studies and the literature, and 20 originated from the municipalities’ lighting master plans. This study shows that there is a need for guidelines and recommendations for working with outdoor lighting from a sustainability perspective, especially in the social dimension of sustainability, where most of the new indicators were identified.