The Argonne National Laboratory’s Systems Assessment Center is pleased to announce the 2021 release of the suite of GREET Models. Please read Summary of Expansions and Updates in GREET® 2021 (948KB pdf) for more details on updates in this version.

• To download GREET.Net and the latest 2021 database please use the following link GREET.Net

• Fuel-Cycle Model: To download GREET_1_2021 please use the following link GREET 1 Series

• Vehicle-Cycle Model: To download GREET_2_2021 please use the following link GREET 2 Series

In response to the technical comments from the Systems Assessment Center and its collaborators that we released on March 21, 2022, Lark et al. provided their responses. In what follows, we review their responses and provide another round of technical comments on Lark et al. responses and their original article to reaffirm and expand our original comments on Lark et al. study . Our original and new comments are supported by literature and observed data. Our interaction with Lark et al. via written comments so far shows that assessment of land use change of biofuels and resulted greenhouse gas emissions is a complicated undertaking, and accurate results requires sound, consistent analytic approach and reliable, representative data.

The Systems Assessment Center and its collaborators provide a detailed technical review of a recently published article “Environmental Outcomes of the US Renewable Fuel Standard” by Lark et al. (2022) . Our review explored modeling approach and data sources for land use changes, types of land conversions, and soil organic carbon changes, among other parameters, in the Lark et al. study, which resulted in significantly high greenhouse gas emissions of US domestic land use changes of corn ethanol presented in that study.