Energy giant SSE said it now has more than one gigawatt (GW), the equivalent of 1,000 megawatts (MW), of onshore wind farm capacity in operation for the first time.
The increase from just 40MW six years ago means capacity is now enough to power, on average, about 800,000 homes.
SSE’s milestone comes after rival Scottish Power last June became the first company in the UK to reach the one gigawatt wind power capacity mark.
Companies are investing heavily in renewable energy, urged on by European targets. SSE currently has 30 onshore wind farms in operation, with another 48 in progress.
Ian Marchant, SSE’s chief executive, said: “Passing the one gigawatt milestone for onshore wind farm capacity is a very positive development as we start the New Year.
“With construction work continuing at sites in Scotland, Northern Ireland and the Republic of Ireland, we expect that our operating onshore wind farm capacity will continue to grow significantly in the coming months.”
However Nick Campbell, at energy analysts Inenco, cautioned that the difference between capacity and load factor – how much of their capacity is exploited – is marked with wind power. He put the load factor for wind power at between 25pc and 40pc of total capacity, as opposed to between 65pc and 85pc for nuclear power. “Capacity assumes there will be optimum winds 100pc of the time, which unfortunately is not going to happen,” he said.
Optimum winds may see wind power overload the grid with energy at times, so operators may have to be paid to shut down.
Wind energy sceptics will not have been reassured by the news last month that a wind turbine burst into flames in stormy weather.
Still, even with wind turbines operating at 30pc of their potential, 1GW of installed capacity could power 13,400 Wembley Stadiums or, 850m kettles, based on figures from renewable energy company Myriad CEG.
Shares in SSE rose 12p to £13.03p.