Activity 1 Scope of Work and Methodology Activity 1 Objective: Measure the vehicle fleet's carbon footprint for 2009. Identify the emission reduction...

Activity 1 Scope of Work and MethodologyActivity 1Objective: Measure the vehicle fleet’s carbon footprint for 2009. Identify the emission reduction target goals for 2015 and 2020.Method:Vehicles1.Obtain a list of all vehicles assigned to the authority as of January 2009.2.The list should include the following information about each vehicle: the facility where it is assigned, age, make, model, number of cylinders, and type of fuel3.Gather available data on fuel use for each vehicle and inform accounting if the record keeping methods need to be updated4.Gather data on miles traveled by each vehicleGreenhouse gases1.Obtain information on the arithmetic factors needed to convert fuel combustion to relevant emissions; specifically, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O)2.Obtain information about the relative contribution of each of the three GHG to global warming, which is reported as global warming potentialData Set:Vehicles1.The fleet consists of 150 vehicles that have been assigned to the following facilities: police, transportation services, central fleet services, and the airport.2.Vehicles primarily consist of automobiles, light duty trucks, SUVs, and shuttle busses. 3.Vehicle ages range from 1988 to 2008. 4.Most vehicles are 8-cylinder and operate on regular unleaded gasoline or diesel.5.Two of the older van busses were converted from gasoline to compressed natural gas. These have been performing well.6.Central Fleet has operated a 2007 Toyota Prius with good results.7.Fueling records are maintained for some but not all of the vehicles. Mileage records are consistently recorded for all vehicles.Emission FactorsThe NTA team completed research on methods for converting vehicle miles traveled and fuel usage into GHG emissions. They were surprised to learn that the science behind direct emissions of GHG from fuel combustion is rather complex. Contributing factors include the chemical characteristics of the fuel, the type of engine in the vehicles and even the emission control devices that are on all vehicles used in the United States. They also learned that these factors change as vehicles age or need maintenance and even with every batch of delivered fuel because of variations in chemical composition. To complicate matters even more, the team learned that the way vehicles are used affects not only fuel efficiency but also emission characteristics. As an example, a number of different activities require that cars and trucks operate in idle mode part of the time. The team needed to make a decision about the extent of record keeping and just how much some of the operational factors would affect their GHG analysis. In the end, the decision was made to use data and emission factors that had been developed by the United States Environmental Protection Agency. There tables were easy to use after some practice and were updated as new information becomes available. The team also recognized that using reliable, free government information would be consistent with the practices that other state agencies were using.The team adopted data and information available at:1.Climate Leaders, 2008, Direct Emissions from Mobile Combustion Sources, EPA430-K-08-004, 31p.http://www.epa.gov/stateply/documents/resources/mobilesource_guidance.pdf2.http://www.fueleconomy.gov/feg/findacar.htm