LUNNE

The master planning of sustainable urban nightscapes requires a parsimonious use of artificial light at night (ALAN) to meet societal needs for safety, mobility, economic and social life, while limiting energy consumption, and negative impacts for humans, for the climate and for biodiversity. But in order to promote light sobriety, lighting modifications must be acceptable to the public, and technically feasible. As the suppression of ALAN is not always an acceptable option, it is necessary to understand the constraints and the needs of the different actors in order to promote sustainable urban lighting. The development of Smart Cities and the possibilities brought by the LED technology opens up new strategies to reduce ALAN while controlling its impact on ecosystems and on the quality of life. The LUNNE project addresses several scientific challenges associated with the reduction of ALAN: 1) A more appropriate quantification of the impact of ALAN reduction strategies on ecosystems, through the development of new indicators at different spatial scales. 2) A better knowledge and quantification of the impact of these strategies on people (mobility, safety, nightlife). 3) A better understanding of the obstacles and levers to the acceptability of these urban lighting policies. All three dimensions will merge into multi-factor indices and specific methodologies, providing urban communities with decision-making tools to consider the specificities of their territory when they adapt their lighting. The impact of lighting modifications will be studied by combining the collection of behavioural data in urban observatories, the collection of subjective and social data through surveys, the collection of photometric data through measurements, and the implementation of computational models.