Energy company Centrica is to start construction of Britain's first major new power station in almost five years.
The new plant will provide electricity to more than one million homes
The UK firm, which owns British Gas, said it would invest £400m ($741m) to develop the gas-fired power station in Langage, near Plymouth in Devon.
The new plant will be able to provide electricity for more than a million homes, Centrica said.
Despite worries over the UK's energy supplies, firms have not been building new power stations in recent years.
Centrica said the new combined cycle gas turbine plant would be one of the country's most efficient power stations, and would begin commercial operations as early as winter 2008.
Planning permission for the power station was first granted six years ago, despite objections from local residents.
But Centrica chief executive Sir Roy Gardner said Britain was facing "a volatile wholesale energy market and a predicted reduction of power generation sources in the coming years".
"This major investment signals Centrica's commitment to secure the future energy needs for our British Gas customers," he said.
Centrica said French company Alstom would build and maintain the Langage power station, which would provide electricity for about 11% of the energy company's forecast peak residential demand.
Plans to build a power station in the area had already been considered by three different firms before Centrica decided the project was economically viable.
"This is a welcome move by Centrica which is investing to secure the future energy needs of UK consumers," said Energy Minister Malcolm Wicks.
"Langage will contribute towards the UK's security of supply as new and more efficient power stations are needed in the coming years to replace existing plants."
Centrica's decision to build a new UK power station comes at a time of increasing uncertainly over the future of Britain's energy supplies.
Volatile global wholesale energy markets have led to a number of power suppliers increasing their household electricity and gas bills.
Centrica raised its gas and electricity prices by 22% at the beginning of March, and has recently warned that further price rises could be on the way.
The government's energy review, which is due next month, is expected to call for the building of more nuclear power stations to replace older plants.
However, any such move is likely to run into stiff opposition from environmentalists and residents in the areas where any new nuclear power stations are proposed.