Development and assessment of a new solar heliostat field based system using a thermochemical water decomposition cycle integrated with hydrogen compression

Abstract

A new hydrogen production plant that produces hydrogen at high pressures is proposed. The proposed plant utilizes an electrical and thermochemical hybrid water decomposition cycle. The source of thermal energy for hydrogen production plant is a heliostat-based solar farm with a generation capacity of 1MWe. The aim of this article is to integrate the thermochemical hybrid water decomposition cycle with the heliostat solar farm and with a hydrogen compression system. The plant electrical energy requirement is covered by the supporting Rankine cycle, which provides the required electrical compression power. The produced hydrogen is compressed to 700bar for usage and storage purposes. The hydrogen production plant is modeled and simulated with Aspen Plus software except for the solar farm, which is developed with engineering equation solver software. Both energy and exergy analyses are performed of the hydrogen production plant, and its overall energy and exergy efficiencies are found to be 12.6% and 20.7% respectively. The energy and exergy efficiencies of the proposed and simulated five-step thermochemical water-decomposition cycle are obtained to be 38.2% and 89.4%, respectively.