Techno-Economic-Environmental Assessment of Pyrolysis-Based Power Production From Methane

Abstract

Methane pyrolysis enables low-carbon power generation by converting natural gas into hydrogen and solid carbon without direct carbon dioxide formation. This study presents a comprehensive techno-economic-environmental assessment of an integrated pyrolysis-based combined cycle (T-cycle) and benchmarks its performance against a conventional natural gas combined cycle (C-cycle). Thermodynamic modelling indicates that increasing pyrolysis temperature from 500°C to 1500°C enhances methane conversion (8% to 97%) and fuel LHV (51.73 to 115.3  MJ/kg) but reduces net power output (38.54 to 13.35 MW). At baseline conditions, the T-cycle achieves an ≈54% reduction in specific CO₂ emissions compared with the C-cycle, while the electricity selling price increases from $0.13/kWh to $0.35/kWh. Parametric analyses reveal that reactor pressure improves net power but suppresses methane conversion, highlighting a trade-off between efficiency and decarbonisation. Economic results indicate that electricity price parity between the two systems can be achieved under moderate carbon pricing or through valorisation of solid carbon byproducts, with a required solid carbon price of ≈1023 $/tonne in the absence of a carbon tax. Overall, the results demonstrate the system-level potential of methane pyrolysis as a strategic decarbonisation pathway for gas-fired power generation.