On the Kyoto agreement he said the 10% target was an "important first step".
The move, which could create hundreds of jobs, was unveiled by the Crown Estate - the agency which owns the seabed around the UK.
Earlier this month Prime Minister Tony Blair announced that £100m was being earmarked for wind, wave and solar power.
The farms will be erected at locations around the Welsh and English coast, a Crown Estate spokeswoman said.
Energy Minister Peter Hain hailed the move saying the 18 wind farms would power around 1m households and that was "a very significant contribution to power supply".
On the Kyoto agreement he said the 10% target was an "important first step".
"In addition we have to change the way we live - that's why energy efficiency is increasingly part of our agenda," he told the BBC.
But one of the UK's leading scientific organisations says windpower is not the only way of meeting international obligations.
Need for nuclear?
Sir Eric Ash, chairman of the Royal Society, called for some new nuclear power plants to be built, saying that otherwise he could not see any way in which the government would meet "even the minimal Kyoto targets".
But Mr Hain, who is a former CND campaigner, said he had not seen any applications for new nuclear plants.
Friends of the Earth said the announcement of the wind farms was a tremendous boost for jobs in the energy and engineering sectors.
"There is huge potential for offshore energy in this country and this announcement signals the dawn of a new era," said a spokesman.
Greenpeace said at least 8,000 new jobs could be created by the new wind farms with the potential for a further 28,000 jobs if turbines were built in Britain.
"After 30 years of opposing industrial abuse of our seas, Greenpeace can at last welcome a move to exploit the fantastic renewable energy resources off our coastline," a spokesman said.
"Let's hope this signals a new commitment to developing Britain's renewable energy industry."
