Transportation Energy Efficiency - Box

Terms Used and Calculations Made

The following definitions apply to the discussion here:

• Energy is measured in British thermal units (BTU).
• A passenger-mile traveled is one passenger transported one mile.
• A ton-mile is one ton transported one mile.
• Passenger energy efficiency is the ratio of passenger miles traveled to BTU (or to energy consumed).
• Freight energy efficiency is the ratio of ton-miles to BTU (or to energy consumed).
• Fuel economy is the ratio of miles per gallon of fuel.