Economic and Technical Viability of Solar-Assisted Methane Pyrolysis for Sustainable Hydrogen Production from Stranded Gas in Nigeria

This study presents a techno-economic assessment of a modular solar-assisted me-thane pyrolysis pilot plant designed for sustainable hydrogen production in Nigeria using Concentrated Solar Power (CSP). Driven by the need to convert flare gas into value and reduce emissions, the work evaluates a hypothetical 100 kg/day hydrogen system by integrating a methane pyrolysis reactor with a solar heliostat–receiver field. Process modelling was carried out in DWSIM, while solar concentration behavior was represented using Tonatiuh. Mass and energy balance results show a hydrogen output of 3.95 kg/h accompanied by 12.30 kg/h of carbon black, with the reactor demanding roughly 44 kW of high-temperature heat at 900 °C. The total capital cost of the ≈50 kW pilot plant is approximately $1.5 million, with heliostat and receiver technologies forming the bulk of the investment. Annual operating costs are estimated at $69,580, along-side feedstock expenses of $43,566. Using annualized cost and discounted cash flow approaches, the resulting levelized cost of hydrogen (LCOH) is $5.87/kg, competitive with off-grid electrolysis in the region, though still above blue and gray hydrogen benchmarks. Financial indicators reveal a positive NPV, a 13% IRR, and a 13-year dis-counted payback period, highlighting the promise of solar-assisted methane pyrolysis as a transitional hydrogen pathway for Nigeria.