IT HAS taken years to plan - and almost did not get off the ground at all.

But at last, it looks as if thousands of tenants in Southampton's council homes are going to get unlimited supplies of cheap hot water and heating - thanks to a revolutionary combined heat and power plant which will be built next to the M271 in Redbridge. Now, all city bosses are waiting for is a £5m government grant to pay for replacing heating systems in hundreds of council homes before building work on the plant can be given the go-ahead. A decision on the grant will be made at the end of October this year.

The £40m CHP (combined heat and power) project was given the final green light by Deputy Prime Minister John Prescott.

When complete, the plant will provide a safe and cost-effective source of heating and hot water for 3,440 council homes, nine schools and other buildings in Redbridge, Millbrook and Maybush. Private homes will also have the opportunity to join the scheme. Members of Southampton Rugby Club will be among the first to benefit from the new plant when it comes fully on line in 2007.

Their clubhouse is a few short pipe lengths' distance from the new plant at Redbridge and will be one of the first to be connected up.

Richard Downes, a local neighbourhood warden and a member of the Outer Shirley Regeneration Board, said: "I am delighted that the government has given the go-ahead for the combined heat and power plant.

"It will be the first of its kind in the country and will provide clean, affordable heating and power.

"The difference it will make to the lives of people of all ages living in the areas is just tremendous.

"The combined heat and power plant at Millbrook will be a flagship for future schemes up and down the country."

Construction work is due to begin on the plant late this year or early next year, with a completion date set for 2007.

A huge underground pipe will be dug surrounding the Millbrook estate, which will pipe the hot water generated by the plant to residents' homes.

The water will then be cooled from a scorching 130C to 90C by a series of sub-stations which will be built around the giant pipe.

From there, it will be channelled via hundreds of miles of smaller pipes to heat hundreds of homes in Millbrook and Maybush.

Temporary boilers will be constructed along the ring to generate heat and hot water for some tenants by the end of 2005 before they are powered by the main generator in 2007.

The costs of the plant will be met by Nursling Generating Limited. The company will shell out £25m over the next few years, building the plant and pipework.

The remaining £15m costs of refitting hundreds of homes with up-to- date heating systems will be met by a combination of levies which will be paid by council tenants and a £5m grant from the government agency, SEEDA (The South-East of England Development Agency).

NGL will generate electricity at the gas-powered plant which it will sell to electricity-distributing companies such as Southern Electric on the open market.

According to project bosses - the scheme will also have wider "green benefits." It is estimated that the gas-fired plant will reduce the amount of carbon emissions into the atmosphere in Southampton by 85,000 tonnes a year.

Project manager Peter North said: "Charging to tenants will be lower than with other heating arrangements."

Jane Richards, special projects manager for Southampton City Council's housing services department, said the council had "every reason" to expect that the grant money would be forthcoming.

Executive director for housing, communities and regeneration at Southampton City Council Nick Murphy said: "It will certainly improve life for thousands of council tenants, ensuring they live in warm, comfortable homes while actually reducing their heating bills."