Preliminary assessment of an organic rankine cycle power plant derived by linear fresnel reflector

Abstract

Organic Rankine Cycle (ORC) powered by Linear Fresnel Reflector (LFR) is a promising technology to harvest low-grade heat sources to produce electricity. This technology can be very useful especially in remote and arid areas. This work presents the study of a small-scale LFR-ORC power plant installed in Errachidia, Morocco. Simulations are conducted to evaluate the optical behaviour of the LFR based solar field and the thermal performances of the ORC based power block. Nine working fluids were tested in basic and regenerative ORCs. Results showed that the optical efficiency of the LFR changed considerably along the year and it had a great impact on the overall efficiency of the power plant. In what concerns the overall performances of the power plant, cis-butene was found to be the best choice when using a basic ORC in the power block. It allowed to achieve an annual power production of 7.12 kW with an annual overall efficiency of 5.32%. On the other hand, neopentane was found to be the best choice when using regenerative ORC in the power block. It allowed to achieve an annual power production of 7.99 kW with an annual overall efficiency of 5.97%. Regeneration enhanced the performances of the power plant by 12%.