Concentrated solar driven thermochemical hydrogen production plant with thermal energy storage and geothermal systems

Highlights: • An integration of concentrated solar driven Cu–Cl cycle with thermal energy storage and geothermal systems is investigated. • Thermodynamic analysis is conducted with energetic and exergetic approaches. • The cost assessment studies are conducted for the overall system and its subsystems. • Unit cost of electricity and hydrogen are found to be $0.03/kWh and $2.84/kg, respectively. • The overall energy and exergy efficiencies are found to be 27.4% and 17.3%, respectively. In this study, a concentrated solar and geothermal based integrated system is thermodynamically investigated to produce useful outputs, such as hydrogen, space heating, electricity, and fresh water. The present system consists of a thermochemical copper-chlorine (Cu–Cl) hydrogen production plant, a geothermal system, a trilateral ammonia Rankine cycle power plant, a multi-effect distillation (MED) desalination unit, a parabolic trough collector (PTC) concentrated solar power (CSP) system with thermal energy storage (TES), and a residential heat pump. As a case study, a hypothetical community is considered near Geysers in California. All produced commodities, except for hydrogen, are utilized for domestic consumption purposes in the community. Hydrogen is supplied to fueling stations in California. One of the most critical requirements of the system, high-grade heat for Cu–Cl cycle, is met by PTC CSP with molten salt TES system. Space heating, electricity, and fresh water productions are powered by geothermal energy systems. Several simulations have been conducted for detailed analyses of the proposed system. Energy and exergy analyses are conducted for the overall system and each component. Some of the subsystems are comparatively assessed and sensitivity analysis is performed to investigate the effects of different parameters on the performance of the entire system as well as various subsystem.Cost assessment studies are conducted for the overall system and its subsystems. 5.5 MWp geothermal and 12.97 MWt solar systems produced 296.9 tons of hydrogen fuel at $2.84/kg cost, 47.6 GWh electricity at $0.03/kWh cost with heat and fresh water due to the simulations. Both energy and exergy efficiencies are found to be 27.4% and 17.3% respectively for the overall proposed system at the ambient conditions.