Consistency in Greenhouse Gas Emissions Estimation for Oil and Gas Industry Operations – A Non-Trivial Pursuit

Oil and gas industry operations span the globe, encountering unique operational and business climates in a variety of regions. This reality presents many challenges for companies that are characterizing their greenhouse gas (GHG) emissions and developing GHG management strategies for diverse multinational facilities. For these companies, the consistency, reliability, and credibility of the methodology to derive GHG emission estimates are especially vital. Recognizing this need, the American Petroleum Institute (API) formed a working group to compile recognized “best practices” for emissions estimation methodologies applicable to oil and natural gas industry operations. The resulting Compendium of Greenhouse Gas Emissions Estimation Methodologies for the Oil and Gas Industry was first distributed in April 2001. Its initial release as a “road test” or Pilot Version document was geared toward testing its application to project, facility, or corporate level greenhouse gas emission inventories. Since its release, comments have been received through a number of mechanisms. This paper presents findings from the pilot phase distribution of the API Compendium, including lessons learned from oil and natural gas companies that have integrated the Compendium into their corporate GHG programs. Results from outreach efforts and special studies undertaken to compare the API Compendium with other commonly used protocols are provided. Ongoing efforts by API to ensure global industry consistency and comparability in estimation techniques are also discussed.