Several federal environmental agencies have developed an online calculator for fleet managers that helps estimate gasoline usage, greenhouse gas emissions, air pollutant emissions, and the cost of ownership of vehicles.

The Argonne National Laboratory and Clean Cities have released the Alternative Fuel Life-Cycle Environmental and Economic Transportation (AFLEET) tool, which uses simple spreadsheet inputs. The AFLEET tool provides three calculation methods.

First, the Simple Payback Calculator estimates a simple payback of the purchase of a new alternative-fuel vehicle compared to a conventional counterpart. The calculator factors in acquisition and annual operating costs, as well as average annual petroleum use, greenhouse gases, and air pollutant emissions.

The tool also offers the Total Cost of Ownership Calculator, which estimates the net present value of operating and fixed costs over the years of planned ownership of a new vehicle, as well as lifetime petroleum use, greenhouse gases, and air pollutant emissions.

Lastly, the Fleet Energy and Emissions Footprint Calculator estimates the annual petroleum use, greenhouse gases, and air pollutant emissions of existing and new vehicles, taking into consideration that older vehicles typically have higher air pollutant emission rates than newer ones.

The tool uses data from Argonne's Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) fuel-cycle model to generate well-to-wheels petroleum use and greenhouse emission coefficients for key fuel production pathways and vehicle types.

In addition, the Environmental Protection Agency's Motor Vehicle Emission Simulator and certification data are used to estimate tailpipe air pollutant emissions. Various sources are used to provide default cost data, including the Clean Cities Alternative Fuel Price Report and American Recovery and Reinvestment Act awards.

The AFLEET tool's spreadsheet and user manual can be found here.