Energy Recovery Potential from Fugitive Methane Emission in the Nigerian Upstream Oil and Gas Sector: An Assessment
Abstract
Fugitive methane emissions from Nigeria’s upstream oil and gas sector were quantified to assess their energy recovery potential and the techno-economic and environmental viability of identified methane recovery systems. The study focused on Nigeria’s oil- and gas-producing states, and applied complementary IPCC Tier 1 and Tier 3 methodologies. Tier 1 used activity data and emission factors, while Tier 3 integrated atmospheric methane retrievals from TROPOMI Sentinel-5P satellite with geospatial infrastructure mapping and meteorological data. Potential energy recoverable was estimated from quantified methane emissions using methane’s lower heating value. The techno-economic and environmental viability of the recovery technologies (Vapour Recovery Unit (VRU) and Pressure Swing Adsorption (PSA)) were analysed using financial performance indicators and a comparative fuel substitution analysis. Average methane emissions were estimated at 769.64 Gg CH4/year (21.55 Mt CO2e/yr) for Tier 1 and 1,284.90 Gg CH4/year (35.98 Mt CO2e/yr) for Tier 3. The potentially recoverable energy was calculated at 38,482 TJ for Tier 1, and 64,245 TJ for Tier 3. The techno-economic analysis indicates that both recovery technologies are viable under the base CNG price assumption, although PSA systems outperformed VRUs across several financial indicators and demonstrated stronger price resilience. Replacing firewood and Liquefied Petroleum Gas (LPG) with recovered methane (Compressed Natural Gas (CNG)) reduced combustion-related CO₂ emissions by approximately 55% and 21%, respectively. The study provides evidence that methane recovery in Nigeria’s oil and gas industry can be economically viable and environmentally beneficial under the stated modelling assumptions. The findings indicate the potential of satellite-enabled methane management systems to support climate mitigation and investment decision-making.
Keywords
References
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