Potential Travel Responses to Alternative Highway Pricing and Financing Systems and the Impact of Fuel Consumption and Greenhouse Gas Emissions

Focus Area

Climate Change


Air Quality, Environmental Process






1-2 years

Research Idea Scope

The proposed research would be conducted in several steps:

1. Identify external costs of highway transportation that are sensitive to changes in the level of vehicle-miles traveled and select the best available estimates of their magnitude and reasonable range from the available literature.

2. Identify traveler-paid costs that vary with mileage traveled but are commonly paid in fixed increments because of institutional arrangements, custom, or other reasons, and estimate their per-mile values.

3. Identify the structure and level of taxes currently used to finance transportation infrastructure investments, highway maintenance, and road system administration, including motor fuel, taxes, vehicle registration fees, local property taxes, etc.

4. Identify alternative pricing structures for (1) each component of costs now covered by motor fuel or other transportation-related taxes, (2) each motorist-borne cost component now paid in fixed increments, and (3) each empirically significant external cost element associated with highway travel. One of the alternatives should represent an attempt to maximize the social welfare of the highway transport system by economically efficient pricing.

5. Use available behavioral theories and empirical evidence (e.g., price elasticities) to develop a consistent analytic framework for predicting potential behavioral changes in response to the replacement of existing fuel and other transportation taxes and fees with alternative charge structures based on “internalizing” external costs of highway travel and converting fixed vehicle and driving-related expenses to a per-mile or other variable basis. Behavioral changes of interest should include household vehicle ownership levels and vehicle type choices, household-level or fleet-wide average vehicle utilization and total vehicle-miles traveled, vehicle and fleet fuel economy, trip characteristics (frequency, timing, length, etc.), density of development, motor fuel consumption, and emissions of National Ambient Air Quality Standards criteria pollutants, and greenhouse gases.

6. Assess the willingness of the public to accept new pricing systems and technologies (vehicle based and nonvehicle based) and the perceived privacy issues.

Suggested By

ADC70, Transportation Energy Committee, as specified in the TRB Research Needs Database, 2009. Source Info: ENVIRONMENTAL RESEARCH NEEDS CONFERENCE 2002 TRANSPORTATION ENVIRONMENTAL RESEARCH NEEDS STATEMENTS