We have constructed a simple model to estimate the CO2 emissions of commercialising a gas resource, as a function of eight input variables: such as production techniques, methane leakage, sour gas processing, LNG liquefaction, LNG tanker distances and pipeline distances.
Energy return on energy invested is c20x across piped gas resources and c10x across LNG resources, compared with c7-10x for oil. This supports the rationale for oil-to-gas switching, as commercialising gas will likely emit 0-80% lower CO2 per boe; plus 15-20% lower combustion emissions.
Different resources are compared using our methodology. The lowest CO2 profile is seen for well-managed piped gas (e.g., Norway to Europe). Actual data on US LNG facilities and methane intensities have been added.
Download the model and you can quickly compute approximate CO2 emissions for other resources.