A Review of Fugitive Methane Emissions Detection Technologies for LNG Operations

Liquefied natural gas (LNG) is increasingly central to global energy strategy, positioned as a lower-emission transition fuel. That positioning assumes fugitive methane emissions across the LNG supply chain are well-characterised, yet direct measurement campaigns at LNG facilities have found operator-reported inventories capturing only 59–83% of actual emissions—a gap that legacy emission factors derived from upstream U.S. oil and gas facilities are poorly equipped to resolve. As measurement-based accountability replaces estimation factors in voluntary frameworks and emerging regulation, the question is which technologies are fit for purpose. This review provides a comprehensive, cross-scale assessment of methane-sensing technologies—from component-level leak detection through to satellite surveillance—evaluated against the physical and operational realities of LNG facilities. Trade-offs in sensitivity, spatial and temporal resolution, environmental dependence, and regulatory readiness are assessed to determine where each performs reliably and where it falls short. While technology is mature at the component level, validation data specific to LNG environments is scarce across all scales, and no single platform provides a complete solution. The most consequential gaps are methodological: the absence of standardised validation protocols, inadequate regulatory harmonisation, and a persistent lag between instrument capability and accepted practice. Six recommendations are proposed: standardised field validation protocols, hybrid monitoring frameworks, regulatory pathways that accommodate emerging technologies, measurement infrastructure in LNG-intensive regions, data transparency with top-down/bottom-up reconciliation, and improved monitoring coverage for intermittent and difficult-to-access fugitive emissions. Together, these define a roadmap for closing the gap between current practice and the accountability that credible LNG reporting demands.