ENVIRONMENTAL experts are to explore ways of reducing carbon emissions from Oxfordshire's street lights in a drive to reduce the county's so-called 'footprint'.

Carbon dioxide is the key greenhouse gas believed to be responsible for climate change and 'footprinting' is a way of measuring how much of the gas is being emitted.

Figures obtained by The Oxford Times showed old and unnecessary street lights, traffic lights and illuminated signs across Oxfordshire cost the county council £3.8m a year to run and maintain - and make up nearly 20 per cent of its total carbon dioxide emissions.

Experts think one of the ways the council could cut emissions is by turning off unnecessary lights and switching from old-style filament bulbs to eco-friendly, long-life lights, which use less electricity.

The move to cut carbon dioxide emissions forms the basis of the council's Carbon Management Plan - an action plan detailing how savings could be achieved - set to be launched next month.

And it comes after a recent unanimous vote by Oxford City Council to explore the possibility of turning off some street lights between midnight and 5am.

City councillor Paul Sargent said: "Most light pollution is caused by ageing and poorly-positioned lightning and it's time the city and county councils put their own houses in order."

County Hall has already set itself a target of switching off lights in 100 street signs a year, where regulations permit the change.

Now, the Conservative-run county council has pledged to spend £450,000 over five years to help reduce its carbon dioxide emissions.

A spokesman said: "County Hall has pledged to reduce carbon emissions from its own buildings and activities by 2012, a commitment that has attracted a further £300,000 from the Carbon Trust."