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Retrofit Calculator
This web page discusses the replacement of the retrofit calculator by new modeling tools.
The retrofit calculator was developed to characterize a fleet and calculate the tons of emission reductions a retrofit project would generate. It was replaced by new, more comprehensive models.
The Diesel Emissions Quantifier (Quantifier) is a tool to help fleet owners, school districts, municipalities, contractors, port authorities, and others estimate cost effectiveness and environmental impact of emission reduction technologies that have been added to vehicles and equipment. Estimates are made using specific information about a fleet, such as miles driven, fuel mileage, and others.
The National Mobile Inventory Model (NMIM) can be used to calculate the emission reductions achieved through a real or potential retrofit of highway vehicles. Similarly, the NONROAD model can be used to calculate the emission reductions based on the retrofit of nonroad engines. These models are EPA's recognized tools for calculating emission credits.
Additional information on the use and application of these tools to State Implementation Plans and Transportation and General Conformity is being developed.