A solar powered dryer designed to be completely independent of fuel and electricity costs was built, a total absorber area of 7.3 m~2 produced the heat for drying while 2.9 m~2 of photovoltaics produced the electricity for five 12V blowers needed for forced air circulation. The dryer includes a preheater section and operates in either continuous venting or intermittent venting mode. There are 3 drying levels, each of which contains two drying trays. Fifty-two type T thermocouples measured the temperatures of the absorbers and the drying trays while a relative humidity (RH) / temperature probe measured the RH and temperature in any given tray. Instantaneous insolation values were measured via a Kipp and Zonen solarimeter/solar integrator system. Temperature, RH and instantaneous insolation data were sent to a Campbell Scientific CR10X datalogger and to a Digital 386 Computer for processing. Drying runs were done on 45.5kg and 227.3 kg of wet coconut meat in the continuous vent mode and the intermittent vent mode of the dryer. It was found that for the continuous venting mode the time taken to dry 45.5kg of wet coconut from 50 percent to 7 percent moisture content dry basis (mc db) was 168 hours and the energy used was 683.7 MJ. For the intermittent venting mode the time for drying was 120 hours and the energy was 581.4 MJ.A saving of 28.5 percent of time and 14.9 percent of energy was achieved by recirculation. Similar runs done on 227.3kg of coconut produced a saving of 21 percent of energy.
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