Impact of thermal energy storage integration on the performance of a hybrid solar gas-turbine power plant

• Published in: Applied thermal engineering 2016-07, Vol.105, p.266-275
• Main Authors: Grange, B., Dalet, C., Falcoz, Q., Ferrière, A., Flamant, G.
• Format: Article
• Language: English
• Subjects: Concentrated solar power; Design optimization; Engineering Sciences; Hybrid solar gas-turbine power plant; Systemic model; Thermal energy storage
• ISSN: 1359-4311; 1873-5606
• DOI: 10.1016/j.applthermaleng.2016.05.175

•We model two hybrid solar gas turbine power plants.•We compare different operating strategies.•We evaluate the influence of the heat storage integration.•The heat storage integration induces a high and stable electrical production. The interest for hybrid solar gas-turbine systems (HSGT) in solar power tower plant technologies is growing. This is due to the high conversion efficiency and to the low water consumption that are achieved when a combined cycle is implemented. This paper presents a simulation tool which is dedicated to the performance analysis a hybrid solar gas turbine solar plant featuring a thermal energy storage (TES) unit. This study is conducted within the framework of the French PEGASE project (Production of Electricity from Gas and Solar Energy) which aims at setting up and testing at THEMIS site (France) a demonstration plant based on HSGT technology. The TES unit called packed bed consists in a cylindrical tank filled with spherical rocks. For a given gas-turbine, the designs of the storage and the heliostat field are carried out. Depending on the operating strategy, this work establishes that the integration of a TES unit offers a higher and more stable electrical generation. The TES unit increases, in some case drastically, the daily average solar share of the power plant. Finally it leads to a higher electrical production per unit of fuel consumed.