Solar thermal power plants have been widely studied in recent years as solar energy is efficient, clean, affordable and largely available. The possibility of onverting solar thermal energy into electricity with small scale (lower than 10 kWe) Organic Rankine Cycle (ORC) plants operating at low temperature (lower than 130°C), seems today a viable option. In this paper, a process simulation model of a solar power system is presented. The process simulation dynamic model is implemented using the commercial Transient System Simulation (TRNSYS) software. The power block of the proposed system is modeled using Engineering Equation Solver (EES) and called as an external subroutine in TRNSYS. The solar system utilizes evacuated tube collectors for the production of hot water, this hot water produced then serves as the thermal input for the power generation unit, the ORC. The Organic Rankine Cycle is used to generate electricity through the utilization of R245fa as working fluid and a scroll expander.
The ORC model has been experimentally validated with data obtained from an experimental facility available at the University of Trieste. The model is used to analyze different system configurations and to assess the electrical and thermal energy produced.
