Techno-Economic Analysis of Solar Hydrogen Hybrid Systems with In-Situ and Ex-Situ Hydrogen Production Approaches in Monggis Substation, Sabah, Malaysia

The intermittency of solar photovoltaic (PV) systems poses reliability challenges for off-grid energy systems. This study explores hydrogen energy integration into PV systems via two strategies: in-situ hydrogen production using electrolysis and ex-situ hydrogen supply through periodic external delivery. Three system configurations, base PV-battery, in-situ hydrogen, and ex-situ hydrogen systems, were modelled and simulated using HOMER Pro to evaluate their technical and economic performance. Component sizing was based on local solar potential and load data. Both hydrogen-based systems eliminated unmet electric load and improved battery performance by reducing deep discharges. The in-situ system offered greater energy independence but incurred high capital expenditure (CAPEX) (USD 57,369.75), net present cost (NPC) (USD 101,367.00), and levelized cost of energy (LCOE) (USD 2.39/kWh), with an annual operating expenditure (OPEX) of USD 3403.38. In comparison, the ex-situ system reduced CAPEX by 64% (USD 20,798.25), achieved a significantly lower NPC (USD 32,740.26), and reduced LCOE to USD 0.73/kWh, with an annual OPEX of USD 1170.11. This comparative analysis demonstrates hydrogen’s potential as a long-duration storage solution for off-grid renewable systems. The findings support strategic planning for rural electrification and propose the feasibility of a green hydrogen hub in Ranau, Sabah.