With increased scrutiny of greenhouse gas (GHG) emissions from the consumption of fossil fuels, there is a growing realization that the consumption of natural gas, including its use as a fuel for electricity generation, is set to rise. Growing global need for liquefied natural gas (LNG) to supplement regional natural gas supplies will lead to increased levels of activities to liquefy, ship, store and regasify LNG for its ultimate use. LNG – as a clean energy alternative – will play an increasingly important role in helping nations improve their air quality and ensure a secure and diverse energy supply in the coming years.

This document is designed to provide guidance for the quantification of GHG emissions associated with operations along the LNG value chain, i.e. liquefaction; shipping; loading/unloading; regasification; and storage. The guidance provided includes:
Mapping out of the GHG emission sources associated with the LNG operations chain;Compilation and description of relevant methods for estimating GHG emissions including generic emission factors that may be useful when site specific information is lacking. The main GHGs considered in this document are CO2 that is primarily associated with process heat and combustion emissions, and CH4 that is primarily associated with venting, leakage and fugitive emissions.