School Buses: Implementation Considerations
The following information helps fleet managers consider implementing alternative fuel and advanced vehicle technologies in school buses. It covers vehicles and equipment, fuel and infrastructure, and maintenance and operation. For information specific to your area, contact your local Clean Cities coalition. Also see the U.S. Environmental Protection Agency's Clean School Bus USA program for more information and funding opportunities.
Vehicles and Equipment
Propane and natural gas school buses can cost up to $40,000 more than diesel buses. However, alternative fuel buses typically have lower operational and maintenance costs and can be eligible for significant state and federal incentives and other funding.
Typically, biodiesel blends can be used in conventional diesel buses. Buses fueled with biodiesel blends might require additional maintenance, especially during the first months of use. This generally means more frequent fuel filter changes during the first year of operation.
Hybrid electric vehicle (HEV) technologies are good candidates for school buses because regenerative braking allows the batteries to recharge during the frequent stopping and starting of school bus operation. New York was one of the first states to acquire hybrid electric school buses. The Plug-In Hybrid Electric School Bus Project is introducing plug-in hybrid technologies to school bus applications.
Although ultra-low sulfur diesel (ULSD) is not an alternative fuel, it provides significant emissions reductions when used in vehicles equipped with advanced emission control technologies. All model year 2007 and newer diesel vehicles (powered with model year 2007 and newer engines) are required to use ULSD. Replacing old diesel vehicles with newer ones featuring advanced emissions controls can provide significant emissions reductions. Vehicles can also be retrofit with "clean diesel" technologies.
School bus fleets can also benefit from idle reduction technologies. These devices reduce fuel consumption and emissions, while keeping bus passenger cabins comfortable in hot or cold climates.
Fuel and Infrastructure
Availability, cost, and implementation issues for alternative fuels depend on the fuel type, fuel suppliers, and local market and environmental conditions.
If not already available, the cost of building natural gas infrastructure can be significant. However, entering into supply contracts with local suppliers reduces fuel costs greatly. Propane infrastructure is typically less expensive to install than natural gas infrastructure.
Biodiesel normally can be used in existing diesel fueling infrastructure. It is important to avoid pitfalls related to biodiesel's properties by thoroughly cleaning, maintaining, and inspecting dispensing equipment. For more on biodiesel use and infrastructure considerations, see Biodiesel Handling and Use Guidelines (PDF 1.5 MB). Download Adobe Reader.
Ultra-low sulfur diesel (ULSD) is being distributed via existing infrastructure and sold at retail fueling stations. In California, all diesel fuel had to be ULSD by 2006. In the rest of the United States, most diesel is ULSD until 2010, at which time all diesel must be ULSD. For more on ULSD infrastructure information, see ULSD.
Maintenance and Operation
Most drivers of alternative fuel and advanced technology vehicles notice minimal differences in performance compared with conventional vehicles. In some cases, they notice benefits. Natural gas vehicles operate more quietly than their diesel counterparts. Biodiesel emissions contain significantly less particulate matter (soot). Hybrid electric vehicles have high torque, making them ideal for the frequent starting and stopping of school buses.
When implementing new technologies, fleet mechanics must be trained to ensure the new vehicles are properly maintained. Studies show that costs for proper maintenance and operation of alternative fuel vehicles can actually be less than diesel vehicle costs. For study details, visit the U.S. Department of Energy Advanced Vehicle Testing Activity Web site.
Training is available from many sources, including the vehicle manufacturers and the National Alternative Fuels Training Consortium. Visit the AFDC Technician Training page for more training opportunities.
Additional Assistance
For additional assistance implementing alternative fuel and advanced technology vehicles and infrastructure, contact your local Clean Cities coalition. Or ask an expert a fleet-related question.