The Vehicle Technologies Office (VTO) has supported the development of a number of software packages and online tools to model individual vehicles and the overall transportation system. Most of these tools are available for free or a nominal charge. Modeling tools that simulate entire vehicles and components allow researchers to create and test entire "virtual vehicles." Integration and validation tools help researchers test how multiple components interact. Online tools for fleet managers on allow them to:

The software programs below help researchers analyze how different technologies may interact with the transportation system and overall environment.


Argonne National Laboratory has been developing the GREET (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) lifecycle model since 1995 with support from several EERE offices including VTO. It allows researchers to consistently evaluate combinations of vehicle and fuel technologies. GREET1, the fuel cycle model, allows users to estimate well-to-wheels energy consumption, fossil fuel consumption, greenhouse gas emissions, and criteria air pollutant emissions for over 100 fuel production pathways and 80 vehicle technology options. GREET2, the vehicle cycle model, allows users to run the same calculation metrics for the full vehicle manufacturing cycle from material recovery to recycling. There are currently more than 20,000 registered users of GREET, including government agencies, auto and energy companies, research institutions, universities, and public interest groups. GREET is available free of charge from Argonne National Laboratory. GREET also has a number of “mini-tools” based off of it that are useful.


The VISION tool allows users to model the cumulative potential impacts (energy use, oil use, and greenhouse gas emissions) of advanced light and heavy-duty vehicle technologies and alternative fuels under various vehicle market penetration scenarios through the year 2050.

The tool consists of two Excel workbooks. The first one is a base case of vehicle and fuel market trends to estimate U.S. highway fuel use and GHG emissions to 2050. The second one allows users to modify those base-case vehicle and fuel market trends to reflect alternative scenarios about advanced vehicle and alternative fuel market penetration. In general, VISION reflects data from the Energy Information Administration (EIA)’s most recent Annual Energy Outlook (AEO). However, VISION’s base case has some key differences, such as assuming business-as-usual MPG for conventional internal combustion engines operating on gasoline in the future, assuming no penetration of advanced technology vehicles and alternative fuels, and estimating GHG emissions on a full fuel cycle basis by relying on GREET outputs. The workbooks provide full citations for the data used in the model. VISION is available from Argonne National Laboratory.


The Market Acceptance of Advanced Automotive Technologies (MA3T) model helps researchers better understand how consumers evaluate and adopt new vehicle technologies. The model simulates how the market for advanced vehicle technologies could potentially change depending on a number of technological, behavioral, and economic variables, including technological learning by doing, range anxiety, access to recharging points, daily driving patterns, and willingness to accept new technologies. The model is available for free as an Excel file download from Oak Ridge National Laboratory.


The Buildings, Industry, Transportation and Electricity Scenarios (BITES) tool is an online, interactive framework that allows users to see how changing key inputs into the energy sector would impact energy usage and carbon emissions. Using a number of “what-if?” scenarios, users can compare how potential futures with major changes to electricity generation, buildings, industry and transportation sectors would compare to baseline reference cases. The tool serves a similar purpose to the VISION tool, but includes the buildings and industry sectors in addition to transportation. The tool is available for free online on the National Renewable Energy Laboratory’s website and was developed with the support of the Office of Energy Efficiency and Renewable Energy’s Office of Strategic Programs.

The Office of Energy Efficiency and Renewable Energy has supported the development of a number of other tools, available in its Energy Analysis Resource Library.