6Feb/13Off
A Manmade Island to Store Wind Energy
It would use the oldest and most cost-effective bulk energy storage there is: pumped hydro. During off-peak times, power from the turbines would pump water up 15 meters to a reservoir. To generate electricity during peak times, the water is released to turn a generator, according to a representative.
The plan underscores some of the challenges associated with energy storage for the electricity grid. Pumped hydro, which contributes a significant portion of energy supply in certain countries, is by far the cheapest form of multi-hour energy storage. It costs about $100 per kilowatt-hour, a fraction of batteries, flywheels, and other methods, according to the Electricity Storage Association. (See a cost comparison chart here.) And grid storage is a considered critical to using intermittent solar and wind power more widely.