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
     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
     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