Development of passive dry cooling system for power plants in arid land

Availability of large amounts of cooling water is essential for steam power plants. In inland arid areas, gas turbines are usually used for electric power generation at low efficiency and high operation costs. Dry cooling towers are another option but they are not effective with high ambient temperature. This work explores the use of radiative cooling for power plants and large refrigeration plants in inland arid areas. The work done consists of small scale experiments, mathematical models, a survey of the suitable materials, and a prototype experiment. This article presents the prototype experiment. The mathematical modeling was presented by us in Solar Energy 48(5), 279–286 (1992). A prototype experimental pond, 10m × 25m × 1m, covered with a painted white aluminum sheet was designed, constructed, and tested. The pond was divided into two layers. The experiment was carried out from January to June. Temperatures in the pond at different sections and depths, net radiation, and weather data were measured. At night the results showed an average heat rejection by radiation of 50 W / m 2. These results were comparable with the results of the mathematical model. The net result of the experiment was positive. It demonstrated the suitability of the covered pond as a heat rejection system in places where a sufficient amount of cooling water was not available.