Sustainable production of green hydrogen, electricity, and desalinated water via a Hybrid Solar Chimney Power Plant (HSCPP) water-splitting process

Abstract

This work presents a novel sustainable approach to producing desalinated water (Wdes), green hydrogen (GH2) and electrical energy (Eelc) using Hybrid Solar Chimney Power Plant (HSCPP) coupled with a water-splitting (WatSp) process. The HSCPP consists of a collector, absorber, chimney, bidirectional turbine outfitted with a seawater pool, and water electrolysis (Watelc) cell. The HSCPP harnesses solar energy to heat the air under the collector creating air movement within the structure, passing the bidirectional turbine, and producing Eelc. Sprinklers were fitted within the structure to operate the HSCPP as a cooling tower (CT) in the absence of solar radiation (Solirr). The Watelc cell directly uses the produced Eelc for the production of Hydrogen (PH2) and oxygen (PO2), while the condensed water at the chimney's inner walls was also collected as Wdes. Results revealed that the continuous operation of the HSCPP has an average annual Eelc of 633 ± 10 MWh that could be efficiently used to generate 21,653 kg of GRH2, 173,244 kg of O2 as well as 190,863 tons of Wdes. The overall efficiency of the HSCPP for the PH2 was found to be 18.5%, which is higher than Solar PV (max∼ 6%) and geothermal Rankine (max∼ 15%). These high efficiencies rank this technology as competitive with other renewable hydrogen production technologies. In conclusion, HSCPP has a promising future as a novel and sustainable solar tower technology to produce hydrogen.