Intelligent lighting for darker skies

Heat-sensitive lampposts shine as and when needed

Prototype street lighting technology which will both improve the quality of night skies in urban areas, and cut electricity use, is raising high hopes among campaigners against light pollution.

The technology has been successfully tested in Toulouse, France, where the new lampposts have been installed over a 500 metre section of pavement. The ubiquitous computing (‘ubicomp’) lights are equipped with sensors that detect heat from human bodies. The heat causes the strength of the light to double for ten seconds – returning to a standard ‘dim’ mode when nobody is around. As a result, the night sky will be darker, and the energy consumption of night lighting cut by around 50%.

Alexandre Marciel, Deputy Mayor of Toulouse, is proud of the technology, developed by the Toulouse Highways Department. “Wherever there is a significant urban density, this could make a big difference,” he says.

There is growing awareness that unrestricted street lighting is not only a drain on energy resources, but can interfere with the migration patterns of birds, insects and mammals. John Meacham, from the Campaign For Dark Skies, called the technology “a splendid improvement, and a positive contribution to reducing our carbon emissions”, adding that “all city council lighting engineers should know about this”.

But street lighting is just a beginning for ubicomp solutions. Perhaps the nights are numbered for ever-bright shops and offices, too. – Lorna Howarth

21 January 2010

Lorna Howarth