Design and Optimization of Combined Renewable Systems to Supply Thermal and Electrical Load Needed for Greenhouses

Optimal design of combined renewable energy systems for supplying heat load of greenhouses is studied. It is tried to analyze the system technically and economically so that it would be optimal from both viewpoints. Optimal design is done from technical point of view using TRNSYS software by setting different parts of the system so that besides preheating of the fluid entering the evaporator of the heat pump for increasing the temperature, heat recovery of the ground in maximum heat extraction periods and heat recovery during summer time is occurred. The optimized system is then studied from economical point of view and the final optimized design is then selected by trade-off between economical and technical considerations. Selected model has mean seasonal coefficient of performance of 4.14 for heat pump, borehole length of 150 meters and total solar collector area around 9.42 square meters and the temperature of the fluid in ground cycle would increase up to 0.5 or 1 degrees centigrade. Optimal amounts gained are compared with those obtained from and TRNSYS and MATLAB relation. Finally to supply electrical load homer software is used and the optimum system is chosen considering design conditions.