
The UK is about to become only the seventh nation in the world to have more than two gigawatts (GW) of operational wind power capacity.
The milestone will be passed on Friday when the Braes O'Doune wind farm, near Stirling, begins producing electricity.
Trade and Industry Secretary Alistair Darling described it as a "significant landmark" for the UK wind industry.
The government has set a target for 10% of electricity to be generated from renewable sources by 2010.
The 36-turbine Braes O'Doune wind farm has a generating capacity of 72 megawatts (MW), enough to supply electricity to 45,000 homes in the area, according to the British Wind Energy Association (BWEA).
Maria McCafferty, BWEA's chief executive, said passing the 2GW mark was a "tremendous step forward".
"This is a day for celebrating the achievement of a significant milestone for our industry and underlining the position of wind energy as the true leader in the renewables revolution," she said.
Mr Darling said renewable electricity played a central role in the government's efforts to curb greenhouse gas emissions.
"Wave, tidal and offshore wind power can make a significant contribution in the future, but onshore wind energy is delivering capacity here and now," he said.
"We want 20% of our electricity to come from these green sources (by 2020) and we are working hard on removing any barriers to achieving that aim."
Onshore wind farms have proved to be controversial, with a number of high-profile projects facing fierce opposition from local residents.
Plans to create England's largest wind farm in Cumbria were thrown out last March after campaigners said it would ruin the landscape of the Lake District.
The £55m development would have seen 27 turbines, each 115 metres (377ft) high, erected at Whinash, near Kendal.
And proposals to create one of Europe's largest onshore wind farms on Lewis, the most northerly Hebridean island, have been challenged by wildlife groups.
They say the 181-turbine development will harm important peat bog habitat, and threaten wild bird populations.
However, local councillors on Thursday backed the £500m project, although a final decision on whether the scheme can go ahead is likely to be made by the Scottish Executive.
Despite having some of the best wind resources in Europe, the UK is still a long way behind the world's leading nation on wind power.
Germany has more than 20GW of wind energy capacity, 10 times as much as the UK.