RFA submits comments to CARB on new version of GREET model

In California, the Renewable Fuels Association (RFA) submitted comments to the California Air Resources Board (CARB) on Monday voicing support for CARB’s proposal to transition to a new version of the GREET model, but also recommending several additional improvements. CARB uses the GREET model to estimate direct lifecycle carbon intensity (CI) for fuels regulated under the state’s Low Carbon Fuel Standard (LCFS).

CARB has proposed to use Argonne National Laboratory’s latest version of GREET as the basis of its update to the original California GREET model, which was introduced in early 2008 and has been in use for the past six years. In the comments, RFA’s Geoff Cooper writes, “We believe Argonne’s GREET1_2013 model contains a number of important improvements and updated inputs that more accurately reflect the current CI performance of corn ethanol and many other fuel pathways … it is encouraging to see the LCFS regulation finally catching up to the actual state of the industry.” RFA believes CARB’s migration to the newer GREET version is a step in the right direction, but “several additional revisions to CA-GREET2.0 should be considered.”