Messenger - Vol. 1, No. 2, Page 8 Winter 1992 Can solar cells solve utilities' peak power problems? Imagine receiving a call from your local power company asking you to let them install the latest power company conservation tool-a solar cell array. Well, you may not have to use your imagination for long. The University of Delaware's Center for Energy and Urban Policy Research has received $96,948 from the U.S. Department of Energy to conduct a 14-month evaluation of existing consumer-based electric utility conservation programs and then create a blueprint for incorporating solar energy into the mix. "We know photovoltaics have potential. We're now trying to identify feasible applications," John Byrne, center director, explains. Center research manager Young-Doo Wang and Bill Baron, deputy director of the University's Institute of Energy Conversion, are working with Byrne on the study. Byrne envisions electric companies installing solar cell panels on homes and commercial buildings primarily to help reduce consumer peak-load demand. The reduction could be large enough to actually offset the need to build new power plants, he says, if solar panels can produce enough energy to heat water, run air conditioners and power lights during these high demand periods. Peak-load demand comes when a utility must use all its power plants to supply customers with the electricity they need, usually in the summer during daylight hours. If utilities can't supply enough electricity or can't afford to build new plants-if supply can't keep up with demand-customers would have to live with brownouts and blackouts. Some power companies have begun offering their customers incentives, such as rate discounts, to allow the company to turn off water heaters and air conditioners during peak-load periods, and rebates to purchase higher efficiency electrical appliances. But, Byrne says, solar cells can reduce peak-load demand more efficiently and with less discomfort and inconvenience to consumers. Water heaters are a good example. "There are at present 1 million water heaters across the nation, which electric companies turn off for eight hours a day during the summer," Byrne says. That saves anywhere from 300-700 watts per heater, thus lowering draw when demand is at its highest. Customers receive an incentive payment and the utility off-loads usage during peak demand, but, customers lose normal hot water service until it's time to turn on the heat. What the energy center study may show, Byrne says, is that solar cells can keep the water sufficiently warm to eliminate the need for the utility to serve the heater during peak-load periods. There would be no need for consumers to suffer hours of lost normal hot water service and no need for the utility to supply electricity to reheat their water. "We already know this has potential, and the Department of Energy expects us to identify other demand-side programs that present options for photovoltaic applications," Byrne says. For example, where utilities have programs that turn air conditioning compressors on and off during peak-load demand, solar panels could reduce the amount of off-time and consumer discomfort. The center and the institute, with the assistance of a Delmarva Power & Light staff member, have already begun compiling data. The grant became active on Oct. 15. Several other utilities are cooperating on the project, including Long Island Lighting, Niagara Mohawk, Public Service of Colorado, Pacific Gas & Electric Co., Arizona Public Service Co., Salt River Project, Florida Power & Light, Central & South West Service Co. and Northern States Power. Even though solar energy is considered more practical in states with less population and more hours of sunlight, the interest shown by Northeastern and Midwestern utilities gives an indication its growing acceptance. Another aspect of the research project is to design pilot programs incorporating solar cells into selected utilities' consumer conservation plans. How well these demonstration projects fare could influence the future of the photovoltaic industry, Byrne says. -Barbara Garrison