Vattenfall has won a contract from UK's National Grid in a highly competitive auction to provide a service that will help keep the lights on.

The enhanced frequency response service from a group of connected batteries, at its Pen y Cymoedd Wind Energy Project in south Wales, will support stability in power flows in the electricity network.

Battery PyC will deliver or absorb up to 22MW of electrical power for a duration of up to 15 minutes. It is believed that this will be a first for Wales.

Vattenfall senior development manager Stephen Holdroyd said: “Our four year contract with National Grid means Battery PyC will help maintain stability of power supply on the grid within milliseconds when it’s needed.

"Locating the storage facility at Pen y Cymoedd is a cost effective concept for us and we are excited about what we will learn from this new venture. In fact we have already learnt a huge amount from Naional Grid’s excellent initiative.

“Being smart and clean with the energy people want is at the heart of Vattenfall’s strategy. Projects like Battery PyC will play an important part in the UK’s transition to a low carbon, affordable and reliable energy supply.”