Evaluating the techno-economic feasibility of hydrogen-fuelled reciprocating engines for renewable base-load power generation

Abstract

This study investigates the techno-economic feasibility of a photovoltaic power plant integrated with hydrogen energy storage and a dual-fuel reciprocating engine for gas-to-power and power-to-gas operations. The system is optimised for maximising constant grid supply, minimising CO2 emissions, and lowering the levelised cost of electricity (LCOE) to assess its value in future energy landscape. Multi-objective optimisation identified a configuration with a hydrogen-fuelled engine generator offering a constant 10 MW grid supply with minimal CO2 emissions (78 kg/MWh), at a LCOE of $335.52/MWh. This system comprises a 93 MW PEM electrolyser, a 4 MW compressor, and 29 t of compressed hydrogen storage, within the limits of the industry’s current or projected capacities. A key highlight of the engine-based approach is its ability to readily enhance grid supply through increased diesel consumption without significantly impacting LCOE, provided CO2 emissions stay within acceptable sector cap. This flexibility surpasses alternative technologies. Further analysis explored potential LCOE reductions using global projected data, bringing optimised LCOE values down to $138.76/MWh, making it competitive to current market prices. Sensitivity analysis revealed the LCOE’s highest sensitivity to the discount rate, followed by minimal impact from variations in fuel and electricity prices due to the optimised system configuration. Furthermore, the tightening CO2 emission limits do not affect the optimised system’s performance, except for limiting the maximum achievable grid supply in 2050 by increased diesel reliance.