The comparative analysis on thermal storage systems for solar power with direct steam generation

Two sensible heat storage systems and two latent heat storage systems, in which liquid lead-bismuth eutectic alloy (LBE) is selected as sensible heat storage medium and sodium nitrate is selected as phase change storage material, are investigated for concentrated solar power (CSP) with direct steam generation (DSG) in the present work. The temperature pinch point likely occurs in sensible heat storage system, which restricts the optimization space. The temperature difference distributes more uniformly in latent heat storage system than in sensible heat storage system, and the outlet temperature of steam is far higher in latent heat storage system than in sensible heat storage system. The exergy efficiency is more two times in latent heat storage system than in sensible heat storage system. The three-tank latent heat storage system has the most flexible and effective performance among the four storage systems. (C) 2017 Elsevier Ltd. All rights reserved.