Cogeneration system driven by solar dish concentrators

The objective of this study is the investigation of a cogeneration system for heating and electricity production, which is driven by solar dish concentrators. There is an organic Rankine cycle (ORC) driven by the solar field and produces electricity with its turbine and heating from its condenser. The solar field includes 100 m² of solar dish concentrators with spiral absorber and an insulated storage tank of 4 m³ storage volume. The system is examined parametrically for different pressure levels in the turbine inlet and superheating degree. The system exergy efficiency is maximized for a superheating of 30 K and a maximum pressure equal to 70% of the toluene critical pressure. In this case, the system produces 12.41 kW electricity, 28.55 kW heating, while the energy efficiency is 51.20%, and the exergy efficiency is 20.69%. Moreover, the system is examined for a typical sunny day, and it is found that the electricity production is 125.6 kWh, the heating production 288.86 kWh, the energy efficiency 48.96%, and the exergy efficiency 19.77%. In the end, the simple payback period of the examined system is found at 6.28 years, which is a good value.