Solar Ethanol Reforming System Integrated Concentrating Power and Composite Parabolic Concentrator

Efficient utilization of solar energy for thermochemical energy storage is significant for achieving carbon neutrality. However, conventional solar thermochemical reactors are limited by the spatial radiation modulation capability, and the energy distribution is extremely uneven. There are defects of a large temperature gradient and low energy storage efficiency. Based on the radiation modulation, we proposed a novel ethanol reforming system that comprehensively integrates butterfly solar concentrating and a compound parabolic concentrator. The thermodynamic and optical analyses of the system are performed through simulation and experimental verification, in which the results show that the design of multiple concentrator arrays with hexagonal arrangement can achieve a high concentrating efficiency and good irradiation uniformity. The designed combined compound parabolic concentrator can optimize the light reflection path and heat flow density distribution and achieve efficient radiation regulation. The effect of the localized high-temperature region is effectively reduced, and the optical efficiency and the uniformity of energy distribution are improved, in which the system temperature inhomogeneity is reduced from 65.8 to 52.9%. The conversion and energy storage efficiency distributions of ethanol reforming were improved by 5.1 and 5.8 to 79.2 and 45.1%, respectively. The proposed novel system can facilitate industrialization of solar thermochemical energy storage applications.