Integration of Power-to-Hydrogen Systems in Non-Interconnected Island Grids: Scenario Analysis and Impact on Grid Performance

The integration of non-dispatchable renewable energy generators into small islands with autonomous electricity grids is by no means straightforward, as such systems cannot benefit from interconnections to mainland grids. Given the considerable interest that hydrogen has been generating in recent years as an energy carrier, the study presented in this article assessed two different scenarios for integrating Power-to-Hydrogen plants into the electricity grid of one such island, with a view to identifying optimal solutions for integrating renewable sources and managing any resulting issues. After sizing the plant for both proposed scenarios, the impact of the electrolyzers on the electricity grid was assessed through load flow calculations. The results showed that, for each scenario, the voltage remains close to its nominal value, the load factor increases by 12–13% and overgeneration from renewable sources is eliminated, thus demonstrating how the proper design and management of Power-to-Hydrogen plants can have a significant impact on their integration. Finally, grid losses increase slightly when the electrolyzer is installed in an urban setting, but decrease when installed in a non-urban setting, due to the shorter distance travelled by electricity, suggesting that centralized production near renewable energy plants is preferable to on-site production near hydrogen users.