American Electric Power (NYSE: AEP) annouced that it is expanding its use of large-scale battery technology on its electricity grid by installing six megawatts of sodium sulfur (NAS®) batteries for storage of electricity to enhance reliability, allow for continued load growth, provide support for weak sub-transmission systems, avoid equipment overload and to offset intermittent wind power.
AEP will be adding stationary sodium sulfur (NAS®) battery technology in its West Virginia and Ohio service territories next year. The company will also work with wind developers to identify a third location for NAS battery deployment next year, using the storage capability to help offset the intermittent nature of wind generation.
AEP has placed an order for the three new NAS batteries with NGK Insulators Ltd. of Japan, the manufacturer and co-developer, along with the Tokyo Electric Power Co., of the technology. AEP anticipates delivery in spring 2008.
According to the New York Times:
The cost is very high, $27 million for six megawatts of capacity, or about $4,500 a kilowatt, including the price of substation improvements. Building a gas turbine of that size to meet peak needs would cost substantially less. But the battery system would be able to store power made from wind, a form of generation that does not produce any carbon dioxide. . . .
The batteries can each deliver one megawatt of power — enough to run a medium-size shopping center — for a little more than seven hours. Replenished nightly, they give back about 80 percent of the electricity put into them. Each is the size of a double-decker bus, and installation is not permanent; they can be moved to another site as the need arises.
AEP plans to add two megawatts of NAS battery capacity near Milton, W.Va., to enhance reliability and allow for continued load growth in that area. AEP will also add two megawatts of NAS battery capacity near Findlay, Ohio, to enhance reliability, provide support for weak sub-transmission systems and avoid equipment overload.
“We’re first movers on advanced storage among U.S. utilities, a position we’ve held on a wide number of technologies in our century of existence,” said Michael G. Morris, AEP´s chairman, president and chief executive officer. “Our near-term goal is to have at least 25 megawatts of NAS battery capacity in place by the end of this decade. But this is just a start. Our longer-term goal is to add another 1,000 megawatts of advanced storage technology to our system in the next decade. We will look at the full spectrum of technologies – flow batteries, pumped hydro, plug-in hybrid vehicles and various other technologies in early stages of development today – to determine their feasibility and potential for commercial application.”
"In our view, advanced storage technologies, like NAS batteries, and other emerging technologies to increase customers´ ability to benefit from energy efficiency will play equally important roles in delaying or avoiding costly future investments in new energy delivery or generation infrastructure," Morris said. “I believe other companies will begin deploying storage technologies in the coming years.”
In 2006, AEP installed the first megawatt-class NAS battery system to be used on a U.S. distribution system. That installation, on a substation near Charleston, W.Va., operated by AEP utility unit Appalachian Power, delayed the need for upgrades to the substation. A similar, but much smaller, NAS-based system installed in 2002 at an AEP office park in Gahanna, Ohio, was the first U.S. demonstration of the NAS technology.