Design and assessment of an integrated PV-based hydrogen production facility

Abstract

This study develops a photovoltaic (PV)-based hydrogen production system specifically designed for university campuses, which is expected to lead in sustainability efforts. The proposed system aims to meet the electricity demand of a Hydrogen Research Center while supplying energy to an electric charging station and a hydrogen refueling station for battery-electric and fuel-cell electric vehicles operating within the campus. In this integrated system, the electricity generation capacity of PV panels installed on the research center's roof is determined, and the surplus electricity, after meeting the energy demand, is allocated to cover the varying proportions needed for both electric charging station and hydrogen production system. The green hydrogen produced by the system is compressed to 100, 350 and 700 bar, with intermediate cooling stages where the heat generated at the compressor outlet is absorbed by a cooling fluid and repurposed in a condenser for domestic hot water production. A full thermodynamic analysis of this entirely renewable energy-powered system is conducted by considering a 9-hour daily operational period from 8:00 AM to 5:00 PM. The average incoming solar radiation is determined to be 484.63 W/m2, resulting in an annual electricity generation capacity of 494.86 MWh. Based on the assumptions and data considered, the energy and exergy efficiencies of the proposed system are calculated as 17.71 % and 17.01 %, respectively, with an annual hydrogen production capacity of 3.642 tons. Various parametric studies are performed for varying solar intensity values and PV surface areas to investigate how the overall system capacities and efficiencies are affected. The results show that an integration of hydrogen production systems with solar energy offers significant advantages, including mitigating intermittency issues found in standalone renewable systems, reducing carbon emissions compared to fossil-based alternatives, and enhancing the flexibility of energy systems.