Simulation of a New Hybrid Solar and Organic Cycle as a Combined Cooling, Heat and Power (CCHP) Unit in Off Design Condition

Abstract

In this paper, using parabolic mirrors, a solar field was designed, which was related to a storage tank for a residential complex in the city of Tafresh located in the center of Iran. The design was performed for the existing oils: VP1, THERMINOL 66, THERMINOL 59. Finally, considering an organic cycle with R123 as working fluid and assuming a minimum length required for oil flow rate to reach a specified temperature, VP1 was selected both as working fluid and for the storage system. Position of single-effect absorption chiller in the outlet of the organic turbine in hot seasons for cooling and also using a condenser in cold seasons due to the lack of need for cooling provide the possibility of selecting two different working pressures in the cycle, which leads to increased storage in winter. The overall performance of solar cycle was calculated with variable electrical demand load of 63%. In off-design condition, on the longest day of the year, the considered cycle was shown to be able to uninterruptedly generate power, cooling, and heating for 20 h for hygienic purposes. Also, it could generate power and heating for 10 h and 50 min on average on the shortest day of the year.