19 October 2010, 09:14 BST
The U.S. has not yet seriously considered pumped hydro for new energy storage, according to Energy Secretary Steven Chu.
Pumped hydro storage uses excess electricity to pump water uphill to a reservoir. Then when electricity demand increases, the water is released downward through turbines to generate electricity that is fed into the grid.
On average, pumped hydro storage costs less than $100 per kilowatt hour and is a highly efficient method of storage. By comparison, Secretary Chu said sodium ion flow batteries cost about $400 per kilowatt hour and offer less than 1% of the capacity of pumped hydro.
There are currently only about 40 pumped hydro facilities in the U.S.-all of which were built at least two decades ago.
Chu wants to see a resurgence of pumped hydro to store power produced by renewables and to provide additional stability to the U.S. power grid.
Perhaps the biggest challenge facing the development of pumped hydro is the overall cost of projects. Despite being cheaper on a per-megawatt basis than other forms of energy storage, pumped hydro projects are large-scale projects, typically built to provide about 1,000 MW of storage at a cost of $1 billion to $2 billion.
Read the full New York Times story at the link below.
Source: Sustainable Business
Photo provided by Martin Hsu, Flickr.