Investigation on the mid-temperature solar thermochemical power generation system with methanol decomposition

A novel 1 MWe mid-temperature solar thermochemical power generation system is proposed to improve solar conversion efficiency in this work. The system consists of a parabolic trough solar collector, solar receiver/reactor, syngas storage tank, internal combustion engine (ICE) and heat exchange devices. The fed methanol is evaporated and flows into the solar receiver/reactor for decomposition and to produce syngas (H2 and CO), with the required reaction heat provided by the parabolic trough collector. Different from typical solar power technologies, in the proposed system, solar thermal energy is converted to syngas as chemical energy, which can be stored or utilized efficiently by an ICE for power generation. The thermodynamic performance evaluation results indicate that the annual energy efficiency and solar-to-electric efficiency reach to 33.78% and 18.29%, respectively. A small-scale pilot system with the capacity of 20 kWe is constructed, and for the first time, an industrial-scale mid-temperature thermochemical power generation is realized, which experimentally validates the effectiveness of the novel solar power technology. The research findings provide an alternative means for improving solar conversion performances.