Keeping the wind

Storage solutions for intermittent power go on test

Wind energy may be both green and efficient when the wind’s up and the turbines are spinning, but its role in powering the nation looks less tenable on stifling summer days, when the turbines aren’t turning but power-hungry air conditioning units and desk fans are.

Obviously, wind cannot be stockpiled for later use, but the development of new battery storage for wind-generated power could see the gap between windy days and power demand firmly plugged. Canadian company VRB Power Systems is at the forefront of this technology, with its Vanadium Redox Battery Energy Storage System. This could see the reliance on costly back up from the grid decreasing and even see wind farms acting as back up for the grid itself, providing income and increasing the proportion of green energy use by selling power back.

VRB’s battery is the subject of a new feasibility study published by Sustainability Energy Ireland, which has been testing it at Sorne Hill Wind Farm in breezy County Donegal. It promises to do the job more efficiently than fuel cells, although David Infield, professor of renewable energy systems at Loughborough University, cautions against getting too excited too early about the technology. Except in rather untypical niche applications, he says, the cost of wind energy storage will have to drop a lot to make it viable – or the price of electricity to rise. The primary challenge, he adds, is still “to meet the time-varying demand for electricity in a reliable and cost-effective manner, and in the longer term in a way that is wholly sustainable.” – Iain Aitch

24 June 2007

Iain Aitch