Daily, monthly and annual thermal performance of a linear Fresnel reflector to drive an organic Rankine-cycle system

Abstract

AbstractThe organic Rankine cycle (ORC) coupled with a linear Fresnel reflector (LFR) utilizes a low-grade heat source. This article presents the study of a small-scale LFR–ORC power-generation plant under the climatic conditions of Almatret, Spain. The mathematical modelling is performed using thermodynamic equations and simulations are conducted to evaluate the optical performance of the LFR system and thermal performance of the ORC plant. Therminol-62 is used as a heat-transfer fluid (HTF) in the solar field, whereas NOVECTM 649 is used as the working fluid in the ORC power system. The LFR is integrated with a thermal-storage unit based on a two-tank system and stores the solar thermal energy via a heat exchanger. The thermal-energy output of the receiver tube of the LFR system is 108 kW and thermal losses are 7.872 kW during the peak time operation of a day at 1:00 p.m. The mechanical power output of the ORC turbine is 7.296 kW using the specific design conditions and the two-tank thermal-storage system adds 4 operation hours to the power plant after sunset.