Hydrogen and Battery Energy Storage for Resilient High-Renewable Microgrids: A Multi-Objective Assessment of Cost, Emissions and Employment Under Uncertainty

Stand-alone microgrids with high renewable shares need storage for daily and multi-day balancing. This study compares hydrogen, battery and hybrid storage in five configurations, with and without diesel backup, for a South African residential load. A bus-resolved mixed-integer linear programming model with open hourly data (2012–2021) trades off cost, diesel emissions and employment by ε-constraint analysis; a robust counterpart covers cost, discount-rate and employment-factor uncertainty and 10 weather years. Per kWh delivered, electricity from the compromise designs cost 0.71–1.29 $/kWh; normalising by generation, which includes 30–45% curtailment, understates it 4–7-fold. The hydrogen–battery hybrid was the least-cost fully renewable option (1.30 versus 1.96 and 2.06 M$ with hydrogen or batteries alone), with the battery cycling daily and the tank providing 71 h of autonomy. Robust designs served the load in all 10 years. The findings held under unit-commitment, reserve and wear constraints and across design years, loads, sites and Monte Carlo samples. Carbon prices at EU ETS levels did not displace battery–diesel supply, whereas a 75% cut in hydrogen equipment costs made the diesel-free hybrid equally cheap. Hydrogen adds the most value as a reserve for prolonged deficits, combined with batteries.