Iberdrola is to build the UK’s largest battery linked to a wind farm, said the Spanish group’s ScottishPower unit.

The 50MW lithium-ion battery will store power from the 539MW Whitelee project in Scotland that is currently Britain’s biggest operating onshore wind facility.

The battery – which was approved by the Scottish Government on Monday – is set to be operating by the end of 2020.

Adding large-scale storage capability is seen as a key strategy to allowing variable renewable sources such as wind power to respond effectively to demand. The Whitelee battery will be able to offer services such as reactive power and frequency response to the National Grid.

Scottish Power CEO Keith Anderson said: “This is a significant step forward in the road to baseload for renewable energy.

“By integrating storage technologies with onshore wind, we are blowing away one of the myths about renewable generation not being available when you need it.”

ScottishPower – the UK’s largest onshore wind operator – said it will look to add batteries at more projects.

News of the Whitelee battery comes as it emerged that developer CWL is planning a project of 560MW that would supersede the ScottishPower wind farm as the UK's largest onshore.