Experimental Performance Evaluation of a Modified Solar Ice Maker Powered by Solar Energy
Abstract
A prototype of a modified solar ice maker was constructed and tested for ice making purpose under Cairo climate. Activated Carbon and methanol have been used as the adsorbent - adsorbate pair. The system consists of adsorbent bed containing Activated Carbon (AC-35) mixed with very small particles of copper to increase the heat transfer through the adsorbent bed, copper condenser with circular fins, one valve and evaporator. A flat glass mirror reflector was used to increase the incident solar radiation on the adsorbent bed consequently the regeneration temperature, also an evaporative water cooler was used around the condenser to condense the adsorbate vapor within the desorption process in a hot day. Indoor and outdoor experimental tests were carried out on the solar ice machine. The experimental performance is presented in terms of gross solar coefficient of performance (COP) and quantity of ice produced. The test results show a daily ice production range from 1.38 to 3.25 kg ice/m2 with a solar coefficient of performance (COP) between 0.07 to 0.11 under climate condition of daily solar radiation on the surface of the adsorbent bed range from 12.4 to 25.2 MJ/m2 and daily average ambient temperature range from 21 to 35 °C. An increasing in the condensate methanol of about 1.1 liter was observed with increasing the regeneration temperature from 90 to 120 °C. Despite the simple technology used in the manufacture, the results show good and acceptable performance compared to the results of the research published.