EPA Lifecycle Analysis of Greenhouse Gas Emissions from Renewable Fuels

As part of proposed revisions to the National Renewable Fuel Standard program (commonly known as the RFS program), EPA analyzed lifecycle greenhouse gas (GHG) emissions from increased renewable fuels use. The Energy Independence and Security Act of 2007 (EISA) establishes new renewable fuel categories and eligibility requirements. EISA sets the first U.S. mandatory lifecycle GHG reduction thresholds for renewable fuel categories, as compared to those of average petroleum fuels used in 2005. The regulatory purpose of the lifecycle greenhouse gas emissions analysis is to determine whether renewable fuels meet the GHG thresholds for the different categories of renewable fuel. EPA’s draft results suggest that biofuel-induced land use change can produce significant near-term GHG emissions; however, displacement of petroleum by biofuels over subsequent years can “pay back” earlier land conversion impacts. Therefore, the time horizon over which emissions are analyzed and the application of a discount rate to value near-term versus longer-term emissions are critical factors. The authors highlight two options. One option assumes a 30 year time period for assessing future GHG emissions impacts and values equally all emission impacts, regardless of time of emission impact (i.e., 0% discount rate). The second option assesses emissions impacts over a 100 year time period and discounts future emissions at 2% annually.


  • English

Media Info

  • Media Type: Web
  • Features: Figures; Tables;
  • Pagination: 5p

Subject/Index Terms

Filing Info

  • Accession Number: 01153495
  • Record Type: Publication
  • Report/Paper Numbers: EPA-420-F-09-024
  • Files: TRIS
  • Created Date: Mar 23 2010 3:01PM