Design and analysis of a new renewable-nuclear hybrid energy system for production of hydrogen, fresh water and power

Abstract

This paper investigates an integrated system where solar energy system (with 75 MWp bifacial PV arrays) and nuclear power plant (with 2 × 10 MWt HTR-10 type pebble bed reactors) are hybridized and integrated with a 72 MWe capacity high-temperature solid oxide electrolysis (SOE) unit to produce hydrogen, fresh water, and electrical power. The bifacial PV plant is integrated into the system for supplying electricity with a low LCOE and zero-carbon system. A Rankine cycle is integrated to generate power from the steam that generated from nuclear heat. According to the available irradiance, the steam is diverted between the steam turbine and high-temperature electrolyzer for hydrogen and power generation. A multi-effect desalination unit is also integrated to exploit the excess heat to generate fresh water. A system performance assessment is carried out by energy and exergy efficiencies thermodynamically. The bifacial PV plant is analyzed in six selected latitudes in order to assess the feasibility and applicability of the system. Numerous time-dependent analyzes are carried out to study the effects of varying inputs, such as solar radiation intensity. For 20 MWt nuclear, 75 MWp solar capacity; hydrogen productions are found to be between 0.036 and 0.562 kg/s. Among the Northern Hemisphere latitudes, the peak daily hydrogen production rate is obtained to reach 25.9 tons of hydrogen per day for the 75 °N case, mostly with the influence of low temperature and high albedo. The pitch distance change increased the hydrogen production rate by 28% between 3 m and 7 m tracker spacing. The overall system energy efficiency is obtained between 21.8% and 24.2%, where the overall system exergy efficiency is found to be between 18.6% and 21.1% under the actual dynamic conditions for the 45 °N latitude case.