R&D GREET (Research and Development Greenhouse gases, Regulated Emissions, and Energy use in Technologies) is a full life cycle model sponsored by the Argonne National Laboratory (U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy). It fully evaluates energy and emission impacts of advanced and new transportation fuels, the fuel cycle from well to wheel and the vehicle cycle through material recovery and vehicle disposal. It allows researchers and analysts to evaluate various vehicle and fuel combinations on a full fuel-cycle/vehicle-cycle basis.
The R&D GREET model is specified in the Inflation Reduction Act of 2022 §45V[1] as the methodology to calculate the life cycle greenhouse gas emissions "through the point of production (well-to-gate)" when determining the level of tax credit for clean Hydrogen production until a successor is approved by the Secretary of the Treasury.
The original implementation of the model was made using Excel spreadsheets while a graphical version has also been made using .NET.[2]