The environmental consequences of using alternative lighting technologies are increasingly well established. The global financial crisis of 2007/2008 and concerns over greenhouse gas emissions and energy security provide strong incentives to reduce the intensity and duration of public and private lighting. To minimise the effects of artificial light on natural and semi-natural ecosystems mitigation opportunities should be taken wherever possible.
Our work has identified several broad options that may be adopted by planners and lighting engineers to mitigate adverse ecological effects of light pollution, including:
- preventing areas from being artificially lit
- limiting the duration of lighting
- reducing the trespass of lighting into areas that are not intended to be lit (including the night sky)
- reducing the intensity of lighting
- changing the spectral composition of lighting
These options often have clear additional benefits in terms of energy consumption, carbon emissions and aesthetics. From both aesthetic and ecological perspectives, maintaining and increasing natural unlit areas is likely to be the most effective change.