Batteries Not Included

Tuesday, 02 February 2010 05:37

American Electric Power (AEP) is conducting a community energy storage test program that utilizes lithium ion batteries. The refrigerator-sized units, provided by International Battery, are scheduled to go online by the middle of 2010 and continue into next year. The test is part of a Department of Energy-sponsored grid storage project that includes deployment of smart meters and other technologies by AEP in a 150 sq. mile area in northeast Ohio.

AEP is a power industry leader in using energy storage on the grid to help utilities more effectively use wind and solar power to cut power demand during peak times. The company has already installed sodium sulfur batteries at selected substations, which can provide one or two megawatts of power for a few hours. But for the Ohio test, smaller batteries will be utilized.

Each location will have at least one 25-kilowatt unit installed which can produce one hour of electricity. AEP plans to have 10 units that in aggregate will store 2 megawatts. The test is to show that networks of smaller energy storage boxes can provide the same services as larger units, including supplementing power to the grid during peak times and providing backup in the case of an outage. Another potential application is using storage to ensure that networks of plug-in electric cars don’t overload a local distribution grid.

“You can aggregate these batteries, so you don’t see them as standalone isolated units, but as a family that provides battery storage,” explains Ake Almgren, International Battery CEO. “These units will need to be smart, so that depending on the time of day and price, you can decide when you provide or store energy.” A single 25-kilowatt battery could supply power for five homes or a shopping center for about an hour, Almgren added.

S&C Electric, the systems integrator on the project, said that distributed storage architecture reduces power losses during transmission, makes it easier to use community wind or solar power and allow a utility to use the stored energy to maintain a steady frequency on the grid.

Even if the test proves successful, there are a number of challenges to overcome before community energy storage systems see wide deployment. In addition to cost, the small scale storage units need to operate reliably at temperature extremes and be able to communicate with smart meters and other smart-grid hardware.