Of 12 projects granted guaranteed power prices in the latest auction, most took a strike price of £74.75/MWh. Environmental and renewable-energy groups said the 50 percent plunge in the cost of power from turbines sited in the sea indicates that clean-energy technologies are quickly rivaling traditional forms of generation without heavy subsidies.
Along with offshore wind farms, biomass and energy from waste plants have secured subsidies for low-carbon energy in the latest auction, with a total of 11 successful schemes.
He said the Government would be setting out ambitious proposals to seize industrial opportunities as the world moved to a low-carbon future, in its forthcoming "clean growth plan" which is due to be published in the autumn.
Greenpeace head of energy Hannah Martin said: "This record breaking price drop from offshore wind marks a huge moment for the United Kingdom energy sector".
Expectations among the offshore wind industry were high ahead of today's announcement that the sector would deliver a serious improvement in costs.
Factors included the downturn in the oil and gas sector, the availability of larger turbines and a more competitive supply chain.
Some three gigawatts of electricity will be generated from the 11 new projects, enough to power 3.6 million homes, the government said.
"We knew today's results would be impressive, but these are astounding".
"We still think nuclear can be part of the mix - but our industry has shown how to drive costs down, and now they need to do the same", she said. "To continue to see costs reduce, a clear pipeline of projects well into the 2020s will be required and the government's forthcoming clean growth strategy must ensure that the £730 million earmarked for auctions of less established technologies during the last parliament will be committed by 2020 as originally planned".
Caroline Lucas, the co-leader of the Green Party, said the figures achieved should be the "nail in the coffin" for new nuclear. Samuel Leupold, Executive Vice President and CEO of Wind Power at DONG Energy, says: "We have always promoted size as a key driver for cost".