Techno-economic Assessment of a Hydrogen-based Islanded Microgrid in North-east

Currently, renewable energy-based generators are considered worldwide to achieve net zero targets. However, the stochastic nature of renewable energy systems leads to regulation and control challenges for power system operators, especially in remote and regional grids with smaller footprints. A hybrid system (i.e., solar, wind, biomass, energy storage) could minimise this issue. Nevertheless, the hybrid system is not possible to develop in many islands due to the limited land area, geographical conditions, and others. Hydrogen as a carrier of clean energy can be used in locations where the installation of extensive or medium-scale renewable energy facilities is not permissible due to population density, geographical constraints, government policies, and regulatory issues. This paper presents a techno-economic assessment of designing a green hydrogen-based microgrid for a remote island in North-east Australia. This research work determines the optimal sizing of microgrid components using green hydrogen technology. Due to the abovementioned constraints, the green hydrogen production system and the microgrid proposed in this paper are located on two separate islands. The paper demonstrates three cost-effective scenarios for green hydrogen production, transportation, and electricity generation. This work has been done using Hybrid Optimisation Model for Multiple Energy Resources or HOMER Pro simulation platform. Simulation results show that the Levelized Cost of Energy using hydrogen technology can vary from AU$0.37/kWh to AU$1.08/kWh depending on the scenarios and the variation of key parameters. This offers the potential to provide lower-cost electricity to the remote community. Furthermore, the CO2 emission could be reduced by 17,607,77 kg/year if the renewable energy system meets 100% of the electricity demand. Additionally, the sensitivity analysis in this paper shows that the size of solar PV and wind used for green hydrogen production can further be reduced by 50%. The sensitivity analysis shows that the system could experience AU$0.03/kWh lower levelized cost if the undersea cable is used to transfer the generated electricity between islands instead of hydrogen transportation. However, it would require environmental approval and policy changes as the islands are located in the Great Barrier Reef.