Power production of an ORC system using a stratified molten salt as thermal energy storage integrated in a CSP plant

The use of Organic Ranking Cycle (ORC) systems to produce electrical energy in Concentrating Solar Power (CSP) plants has been significantly increasing over the recent years, mainly for small size plants [1-2]. The project ORC-PLUS, in the frame of Horizon2020, aims to deepen this aspect for an existing CSP plant located in a desert area at Ben Guerir in Morocco and using linear Fresnel collectors as well as thermal oil as heat transfer fluid (HTF). This plant foresees mainly two different operative modes: during daytime with sufficient Direct Normal Irradiance (DNI) an Organic Rankine Cycle (ORC) system is directly coupled to a 7 loops solar field; after sunset the ORC is fed by a thermal storage coupled to an additional solar field consisting of 3 loops. In the same context the performances of a stratified molten salt as thermal energy storage (TES) are deepened at ENEA CR Casaccia in Italy. Aim of this paper is the analysis of the power production of the 1 MWe ORC system present in the plant, under different operating conditions using a proper computing model.The use of Organic Ranking Cycle (ORC) systems to produce electrical energy in Concentrating Solar Power (CSP) plants has been significantly increasing over the recent years, mainly for small size plants [1-2]. The project ORC-PLUS, in the frame of Horizon2020, aims to deepen this aspect for an existing CSP plant located in a desert area at Ben Guerir in Morocco and using linear Fresnel collectors as well as thermal oil as heat transfer fluid (HTF). This plant foresees mainly two different operative modes: during daytime with sufficient Direct Normal Irradiance (DNI) an Organic Rankine Cycle (ORC) system is directly coupled to a 7 loops solar field; after sunset the ORC is fed by a thermal storage coupled to an additional solar field consisting of 3 loops. In the same context the performances of a stratified molten salt as thermal energy storage (TES) are deepened at ENEA CR Casaccia in Italy. Aim of this paper is the analysis of the power production of the 1 MWe ORC system present in the plant, under dif...