STREET lights will be permanently removed from 40 sites around Bucks after a trial - including on seven roads where accidents during darkness have gone up.

Three sections of the A413 and two parts of the A40 will go dark permanently despite small increases in collisions during the three year experiment.

The Wycombe Road (C100), running from the M40 Handy Cross roundabout junction to Marlow Bottom, and the A416 Amersham to Chesham are the other sites where crashes went up but will lose their illuminations nonetheless.

The lights were turned off to save money and energy.

Buckinghamshire County Council said its trial saved £260,818 in energy costs, carbon emissions savings of 1,625 tonnes of CO2 and reduced energy consumption of 3,108,797kWh.

Removing the lights will now cost about £850,000.

In the long run, however, officials said they would be saving about £4million in maintenance costs.

Cllr Peter Hardy, Cabinet Member for Transport, explained why lights are going for good at the seven sites where there has been a rise in accidents during darkness.

He said: "Each collision taking place at these sites was fully investigated with all contributory factors being carefully considered before the recommendations were made to me. It was apparent that the lack of lighting was not a factor in these collisions."

The council's study showed that the number of recorded injury collisions at the switch off sites during darkness, when averaged across all sites, have reduced by 26 per cent.

Collisions increased at 11 sites, reduced at 26 sites and there was no change at the other nine sites.

The other four sites where crashes went up will have their lights put back on.

There were 259 responses to the consultation on the switch off, which officials described as 'wide ranging'.

The report stated: "Many respondents confirmed their support for the aims of the trial, namely to reduce costs, energy use and light pollution.

"Other respondents reiterated concerns or opposition previously expressed either about the trial generally or about the impact of the trial at specific locations.

"There is no consensus for or against the trial and this supports the decision to look at each site on its own merits before deciding what the final decision is at each trial site."

The council estimates it will save £435,429 in energy costs between now and 2016.

Work to implement the switch off begins later this year.