Transport officials are bidding to join up with other councils in a joint bid to save more than £100 million on street lighting.

West Sussex County Council is hoping to get approval for the £58million Private Finance Initiative (PFI) contract with the Department of Transport (DfT).

If the bid is successful the authority would be tied into a 25-year agreement with Southampton City Council and Hampshire County Council.

West Sussex council believes the contract could save it £122 million over 25 years because of grants the PFI arrangement would attract.

The proposed contract would commit a private contractor to replace more than 50,000 lighting columns which are over 15 years old in the first five years.

Replacing the old street lights with new modern lights will reduce the impact on the environment by reducing the discharge of greenhouse gases and the effects of light pollution.

Energy saving changes include changing illuminated traffic signs and bollards so they can be switched off during the day, rather than being continuously lit up.

A spokesman for the Automobile Association said: "It looks like a good thing. We are always concerned about PFI agreements because the bind people into a contract for such a long time.

"The main thing we are concerned about with street lighting is authorities are looking for ways to better turn them off.

"Some authorities are discussing switching the street lights off between midnight and 4am.

"We have grave concerns about that, not only from a driver's point of view.

"Pedestrians knocked over during the night are invariably drunk, and these moves make them harder for drivers to see.

"Street lighting is also a prominent crime deterrant.

"Our main concern is that whether or not the new system will allow the council to turn the lighting off much easier, allowing them to go down that route."

Current targets of 98 per cent of lights operational and a five-day response time for repairs will remain the same.

The investment follows a review in 2000 of street lighting in West Sussex.

The council discovered major investment was needed to replace ageing and broken street lights.

In July 2003 a previous Private Finance Initiative (PFI) bid was unsuccessful.

The DfT has asked West Sussex, Hampshire, and Southampton Councils to submit an outline business case by the end of March 2007.

The department will then decide whether to approve the bid.