Switching off all lights outside operating hours, including illuminated signs

Why switch off all the lights during periods of inactivity? Lighting is often one of the largest energy consumption items in buildings. Switching lights off during periods of inactivity therefore reduces energy consumption and, as a result, the environmental impact of the premises. In addition, this eco-gesture helps fight light pollution, which is harmful to animals and humans. Indeed, light masks the cycles of natural light and is therefore likely to alter individuals’ behaviours and biological rhythms. Moreover, light pollution impairs the quality and duration of sleep and causes a decrease in the “sleep hormone”, melatonin, which can affect, among other things, anti-inflammatory, antioxidant and immunostimulating properties. Since 7 October 2022, illuminated signs have been subject to a regulation aimed at protecting fauna and flora: they must be switched off between 1 a.m. and 6 a.m. (Hours may vary depending on the activity and on decisions taken by the prefect.) How to switch off all the lights during periods of inactivity? To switch off all the lights during periods of inactivity, here are a few suggestions: • Use timers or motion detectors in circulation areas or little-used areas. These devices can be programmed to switch the lights off automatically after a period of inactivity or when no one is detected in the area. • Use central switches: group the lighting switches of each area or room and use a centralised switch to turn them all off at the same time. This makes it easier to switch off the lights at the end of the day or when the area is not in use. • Invest in smart lighting systems, such as presence-detection lighting or lighting controlled by building management systems, which can be programmed to switch the lights off automatically when no activity is detected. • Encourage individual responsibility by making employees aware of their own responsibility for saving energy and encouraging them to switch off the lights when they leave a room. It is important to create a company culture focused on sustainability and energy efficiency. By combining these different approaches, the process of switching off the lights during periods of inactivity is made easier. How to find out the annual cost of lighting? Here is the calculation method: Lighting power (in W) x operating time (in hours) x number of days per year / 1000 = consumption in kWh x cost per kWh (€0.27 excl. VAT*) = annual cost of lighting. *Cost given as an indication; it depends on your subscription.

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France