LONDON (AFP) — Britain is to build the biggest biomass plant in the world, Business Secretary John Hutton said after giving the green light to the renewable energy project.

The 350-megawatt wood chip-fuelled electricity generating plant will be sited in the industrial town of Port Talbot on the south Wales coast. It will cost 400 million pounds (830 million dollars, 560 million euros) to construct.

"This will be the biggest biomass plant in the world, generating enough clean energy to power half the homes in Wales," Hutton said in a statement.

"It joins eight major renewables projects already given the green light in the past 12 months alone and is another important step towards the low carbon economy envisaged by the Prime Minister (Gordon Brown)."

The plant is expected to contribute about 70 percent of the Welsh Assembly's 2010 renewable energy target, and have a 25-year lifetime. It will create around 150 new jobs.

The wood chip fuel, to be burnt around the clock, is expected to come from sustainable sources in the United States and Canada. The station will burn around three million tonnes per year.

There has been a local campaign against the proposal, with 7,000 people signing a petition.

Neil Crumpton, energy spokesman for Friends of the Earth, told AFP the group was in favour of biomass projects but did not support this one due to its location.

Even if there was little pollution, the area around the site already suffered from above average levels, he said, adding that the plant would only produce electricity, while similar stations produce heating as well.

Doug Parr, Greenpeace UK's science spokesman, also lamented the fact it would not produce heating too and expressed concerns about the wood being transported over the Atlantic Ocean.