The company was branded ‘disappointing’ earlier this month for putting up prices by on average 19%.

But, through its renewables arm, known as ScottishPower Renewables (SPR), the company has become the first in the UK to reach the one gigawatt mark of electricity production capacity from wind power.

The milestone was hit after the company officially opened new wind farms at Arecleoch (120MW) and Mark Hill (56MW) in South Ayrshire, Scotland.

SPR now has 24 wind farms fully operational across the UK boasting more than 770 turbines after an investment of more than £1 billion in wind energy in that last decade.

Scotland’s first minister, Alex Salmond, said: “It is through the leadership of companies such as ScottishPower Renewables that we have made such progress and why, as we increasingly develop our offshore energy resources.

“I am confident we will achieve our target for Scotland to generate from renewables the equivalent of 100% of our own electricity needs by 2020.”

Owners of SPR Iberdrola’ chairman, Ignacio Galán, said: “This clearly shows our commitment to clean energy and sustainable development in Scotland.

“Our company is deeply committed to Scotland, and seeks to be a driver of growth and development, especially in the difficult international economic environment we are currently experiencing.”

Luke Walsh

Action inspires action. Stay ahead of the curve with sustainability and energy newsletters from edie