This report was a joint effort from the National Renewable Energy Laboratory, Sacramento Municipal Utility District, prepared for the American Solar Energy Society at the Solar 1995 Conference. This report has equations to use to calculate solar loop gain and tank losses. Analysis is based upon the tank energy balance – identifying solar gain during the day and tank losses at night. These gains and losses can be compared to expectations based upon prior knowledge and estimated weather conditions. These calculations can prove to be useful where los resolution of energy flow is adequate and costs must be kept very low.
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