Methane by the Numbers: The Need for Clear and Comparable Methane Intensity Metrics

TL;DR

The paper argues for standardized methane intensity metrics to accurately compare emissions from oil and gas operations.

Contribution

The study identifies three unbiased methane intensity metrics that avoid biases caused by ignoring coproduced oil and liquids.

Findings

Half of the analyzed methane intensity metrics are biased due to exclusive attribution to gas production.

Three metrics are shown to be computationally equivalent when benchmarked against total energy production.

Recommended metrics allow for straightforward calculation of embodied intensities across supply chains.

Abstract

Global efforts to
track methane emissions from oil and natural
gas operations have recently converged around measures of methane
emissions intensity, including emergent requirements for reporting
as part of import standards. However, multiple definitions of methane
intensity have led to conflicting approaches that hinder clear comparisons
among regions and obstruct the development of effective policy. This
study analyzes six of the predominant methane intensity metrics and
shows how half, by attributing methane exclusively to gas production
while overlooking coproduced oil and liquids, can bias comparisons
among jurisdictions and have limited practical utility. These simple
loss rates are strongly dependent on gas-oil ratios and tend toward
meaningless infinite methane intensities in oil-dominant operations.
The three remaining metrics overcome this limitation and are recommended
as unbiased and directly intercomparable measures of methane performance.
We further show how these latter metrics, which effectively benchmark
methane emissions against total energy production, are computationally
and functionally equivalent when emissions are allocated to oil and
gas operations using energy production. Finally, we address the challenge
of propagating emissions through the supply chain and demonstrate
how, for the recommended intensity metrics, embodied intensities of
any facility’s outputs can be easily calculated from feeder-facility
intensities and energy production.

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