flywheel

Williams Advanced Engineering's flywheel technology is being used on the Scottish Isle of Eigg and Fair Isle to stabilise the power grid.

The installations are the first grid-connected flywheels used in a European energy network. Funding has come from the UK Department of Energy and Climate Change to balance power coming from the islands’ renewable power supplies.

The flywheels come directly from Williams Advanced Engineering who developed the technology for use in Formula 1 kinetic energy recovery system (KERS) but were not used because battery technology was chosen instead.

The flywheel is a kinetic system that absorbs and transmits power to and from an electrical grid. It spins at a high speed in an airtight container to store the energy as rotational energy that can be converted back to electrical energy by slowing down the flywheel. 

Robert Mitchell, director of Fair Isle Electric Company, explained the island's need for a flywheel:“Our two wind turbines produce more than enough power most of the time but they cannot store energy so this will be an excellent addition.”

Both islands rely heavily on intermittent renewable energy sources. The Isle of Eigg, in the Inner Hebrides, uses a bank of lead-acid batteries to store energy and smooth the supply. Fair Isle, south of the Shetland Island group, uses diesel generators when there is insufficient wind generation.