Carbon Footprints for Public Transportation Agencies in Florida

Under sponsorship of the Florida Department of Transportation, a study was conducted to measure the carbon footprint for Florida's public transit agencies. The state's 31 public transportation agencies were contacted to obtain data. With the Climate Registry's general reporting protocol (GRP), the research team calculated emissions on the basis of the provided data. The research team found that carbon dioxide emissions from revenue vehicles accounted for 82.5% of a typical agency's emissions (86.5% if weighted by footprint size). The balance of the footprint included trace emissions from vehicle operations; emissions from purchased electricity; emissions from operating nonrevenue vehicles; emissions from fuel used to heat, operate, and maintain facilities; and refrigerants lost from vehicle and building air-conditioning systems. Refrigerant losses accounted for about 5% of a typical agency's footprint. Data on losses were the most difficult to collect. The collected data were estimated to account for 75% to 80% of the total carbon footprint of Florida's transit agencies, and the data total footprint accounted for less than 1% of the state's surface transportation carbon footprint. This research also examined how Florida's transit agencies could help reduce the state's transportation carbon footprint by providing service that encourages people to ride public transportation instead of driving. The study also provides lessons for conducting similar inventories elsewhere, including data collection, constraints on agencies' abilities to provide data on a voluntary basis, some limitations of the GRP, and possibilities for simplifying the process in some circumstances.