A fuel or advanced vehicle can impact our economy, environment and society across many stages in its life cycle. Tools to assess these impacts are vital to making informed decisions on how to advance and manage these technologies and direct future research and development.
One tool leading the way is the GREET® (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) model, the industry standard tool for evaluating energy use and environmental impacts of fuels and advanced vehicles.
GREET® is a suite of lifecycle analysis models developed at Argonne with support from the U.S. Department of Energy’s (DOE) Office of Energy and Efficiency and Renewable Energy. It provides a consistent and transparent platform for evaluating advanced vehicle powertrain and fuel production technologies, and assessing their energy use and environmental impacts.
Features of the tool
GREET® was first developed in 1995i and is continually enhanced for better functionality and user ease, and to stay current with technological changes. It now boasts over 35,000 registered users globally. It is used by government agencies, the automotive industry, the energy industry, research institutions, universities, and public interest groups throughout North America, Europe and Asia.
The model is holistic; it generates results of energy use, greenhouse gas emissions, common air pollutant emissions, and water consumption associated with the production and use of conventional and advanced vehicle/fuel systems. Fuels can include petroleum, and natural gas-derived fuels, biofuels from various feedstock sources, various electricity generation technologies, and hydrogen production pathways; and vehicle systems can include internal combustion engines, plug-in electric vehicles, and hydrogen fuel cell electric vehicles. The model also evaluates the impacts of the vehicle production cycle including key vehicle components such engines, vehicle bodies, and motive batteries. Together it covers all transportation applications, including light-duty, medium-duty and heavy-duty vehicles, rail, aviation and marine.
Analyzing the impact of proposed fuels and engines
GREET® has played a role in supporting the research and development of new fuels and engines. In determining whether new fuels or engines are viable and market-ready, developers must first understand the impact of their production and use on the environment and economy. GREET® supports this analysis by evaluating how much energy new engines and fuels use and the emissions they produce over the vehicle’s lifetime, from mining raw materials through vehicle disposal.
Researchers working with U.S. DRIVE, a government-industry partnership, and DOE’s Co-Optima Initiative, which tackles fuel and engine R&D simultaneously, have leveraged GREET® in this manner. GREET® has helped them evaluate the impact of new fuel/engine combinations on emissions, fossil-fuel consumption and job creation. These insights contribute to the knowledge required to make investment decisions, break down barriers to commercialization, and bring new high-performance fuels and advanced engine systems to market sooner.
Battery production and recycling
When integrated with other models, applications for GREET® extend even further. Argonne has demonstrated this by integrating Argonne’s BatPAC (Battery Performance and Cost) model–which assesses battery performance and costs– and the GREET battery LCA module into its newly developed ReCell model. Doing so effectively closes the loop on the battery life cycle by providing a set of tools that enable battery makers, recyclers and other stakeholders to evaluate the economic and environmental impacts of making, using and recycling battery vehicle technologies. Such insights will prove to be increasingly valuable as millions of batteries from vehicles sold over the past decade reach their end of life.
Please visit http://greet.es.anl.gov for GREET® models, documents, publications, and GREET-based tools and calculators.