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Field Performance of Photovoltaic Solar Water Heating Systems.

pdf icon Field Performance of Photovoltaic Solar Water Heating Systems. (1073 K)
Fanney, A. H.; Dougherty, B. P.; Kramp, K. P.

International Solar Energy Conference. Proceedings. Solar Engineering 1997. Held in Conjunction With The Solar Energy Forum. American Society of Mechanical Engineers. April 27-30, 1997, Washington, DC, American Society of Mechanical Engineers, New York, NY, Claridge, D. E.; Pacheco, J. E., Editor(s)(s), 171-182 pp, 1997.

ASME Journal of Solar Energy Engineering, Vol. 119, 265-272, November 1997.


American Society of Mechanical Engineers, New York, NY


water heaters; solar; Florida Solar Energy Center; Great Smoky Mountain National Park; solar collectors; solar energy


Energy consumed for water heating accounts for approximately 17 quads of the energy consumed by residential and commercial buildings. Although there are over 90 million water heaters currently in use within the United States, durability and installation issues as well as initial cost have limited the sales of solar water heaters to less than 1 million units. Durability issues have included freeze and fluid leakage problems, failure of pumps and their associated controllers, the loss of heat transfer fluids under stagnation conditions, and heat exchanger fouling. The installation of solar water heating systems has often proved difficult, requiring roof penetrations for the piping that transports fluid to and from the solar collectors. Fanney and Dougherty have recently proposed and patented a solar water heating system that eliminates the durability and installation problems associated with current solar water heating systems. The system employs photovoltaic modules to generate electrical energy which is dissipated in multiple electric elements. A microprocessor controller is used to match the electrical resistance of the load to the operating characteristics of the photovoltaic modules.