Propane Bus Project
Camas School District has purchased 27 propane buses to diversify its diesel fleet. Designed and built for maximum quality and reliability, these busses meet all applicable School Bus Federal Motor Vehicle Safety Standards (FMVSS). They utilize the latest advancements in propane technology.
In order to provide on-site fueling for the new propane buses, the District has contracted with Ferrellgas to provide an on-site fueling station at the existing Camas School District Transportation Center.
Propane, also known as liquefied petroleum gas (LPG), is the most widely used alternative fuel in the United States due to its high energy density, clean burning properties, established infrastructure, and domestic availability. Propane is also the third most used vehicle fuel, behind gasoline and diesel.
A colorless and odorless liquid, propane is a mixture of hydrocarbons found in natural gas and is refined from crude petroleum. Propane has a high octane rating and is usually less expensive than gasoline. Propane-fueled vehicles emit less carbon dioxide and fewer smog-forming air pollutants than gasoline-powered vehicles. Propane is non-toxic and presents no threat to soil, surface water, or groundwater.
Propane has the lowest flammability range and one of the highest energy densities of all alternative fuels. Still, a gallon of propane has about 25 percent less energy than a gallon of gasoline.
For easier distribution, propane is liquefied through pressurization. The fuel is stored under pressure inside the tank and when pressure is released, the liquid propane vaporizes and turns into a gas that is used for combustion.
Propane is used mainly by fleets because propane vehicles have a good driving range and the gaseous state of propane eliminates cold start problems associated with liquid fuels. Propane is also popular because of lower maintenance costs. Propane engines have been documented to have an engine life up to two times that of gasoline engines. For example, Portland Public Schools’ buses have been fueled by propane since 1985.
Benefits of Propane-Powered Buses
- Propane exhaust creates significantly less smog-forming and toxic air pollutants than gasoline or diesel.
- Propane is considered an alternate fuel under the Energy Policy Act of 1992.
- 85% of propane fuel (LPG) used in the U.S. comes from domestic sources.
- Propane is less expensive per gallon than gasoline or diesel.
- Propane vehicles have the longest driving range of any alternative fuel, more than 250 percent farther than compressed natural gas, about 60 percent farther than methanol, and 25 percent farther than ethanol.
- Those who drive propane-powered vehicles say that there are no significant driving differences between dedicated propane vehicles and diesel-powered ones.
- Many propane vehicle fleets have reported 2 to 3 years longer service life and extended intervals between required maintenance compared to diesel vehicles.
- Propane vehicles have reduced cold start issues than diesel vehicles.