Alternative Fuel School Buses
- Don't all school buses on the road have to meet minimum safety standards?
- Aren't all school buses on the road required to meet today's pollution standards?
- Aren't new diesel school buses as clean as natural gas buses?
- Doesn't the higher price of natural gas buses makes them impractical?
- Isn't the natural gas bus a new, unproven technology?
- Do natural gas buses pose increased risks?
- Wouldn't increases in natural gas prices make the buses extremely costly to run?
Don't all school buses on the road have to meet minimum safety standards?
No. Although new buses must meet a stringent series of federal motor vehicle safety standards, there are about 5,000 school buses on the road that were built before these standards were required. These older buses did not have to meet safety requirements for passenger seating and crash protection, rollover protection, body joint strength, and fuel system integrity.
Aren't all school buses on the road required to meet today's pollution standards?
No. It's true that pollution standards for buses have become progressively stronger, providing better protection for children and their maturing lungs. However, buses built before 1990 and 1991 are still on the road; they are allowed to emit six times more toxic soot and three times more smog-forming nitrogen oxides (NOx) than newer models. Older school buses expose children, whether they are riding the bus or waiting for it in the schoolyard, to greater levels of air pollution. In addition, diesel school buses may release more pollution particularly soot under real-world driving conditions than estimated in government laboratory tests.
Aren't new diesel school buses as clean as natural gas buses?
Diesel is inherently dirtier than natural gas. Even the cleanest diesel bus on the road today releases about five times more soot and twice the amount of smog-forming pollutants as a natural gas bus. In addition, the soot released from a diesel bus is more toxic than natural gas emissions. The state of California has listed more than 40 chemicals in diesel exhaust as toxic air contaminants. Numerous studies have linked diesel exhaust with cancer, asthma, bronchitis, and other respiratory illnesses. There have been no studies linking natural gas combustion and cancer, despite the widespread use of natural gas in home heating and cooking.
One school bus manufacturer has installed emission controls for soot in its buses and is marketing a cleaner diesel in California. In order for emission controls to function, diesel buses must use low-sulfur fuel, which will not be nationally accessible until required by federal law in 2006. In addition, the long-term durability of these devices has not been tested. Diesel buses release toxics such as benzene and 1,3-butadiene that natural gas buses do not. According to the U.S. Department of Energy, natural gas buses will always have soot and toxic emission benefits over diesel buses because natural gas combustion inherently produces lower levels of these emissions.
Doesn't the higher price of natural gas buses makes them impractical?
A natural gas school bus initially costs between $30,000 and $40,000 more than a diesel bus. This initial investment is often recouped by school districts that benefit from lower maintenance and operational costs. More importantly, investing in cleaner vehicles pays off in reduced asthma rates, fewer hospital visits, lower cancer rates, less absenteeism, and healthier children.
Isn't the natural gas bus a new, unproven technology?
Natural gas buses have been on the road for more than a decade and have a long track record of success. Approximately one in seven transit buses currently on order in the United States is powered by natural gas, and half of California's new buses use natural gas. Natural gas transit buses are being used in cities throughout the country, including Los Angeles, New York, Tacoma (Washington), Phoenix, State College (Pennsylvania), Cleveland, Dallas, and Atlanta. School districts are learning from these transit districts and joining the clean air bandwagon on alternative-fuel school buses. One hundred thirty school districts in 17 states transport children to and from school in buses powered by alternative fuels.
Do natural gas buses pose increased risks?
The U.S. Department of Energy (DOE) considers natural gas buses to be as safe as their diesel counterparts on the road and possibly even safer during maintenance and refueling. Although both natural gas and diesel fuels are flammable and require specially designed precautions and fire protection equipment, natural gas lacks some of the risks of diesel. In fact, DOE reports that natural gas fuel tanks are much stronger and safer than either diesel or gasoline fuel tanks. Diesel tanks can leak and contaminate groundwater, which is not a risk with natural gas. Diesel bus facilities often store much larger quantities of fuel on site than natural gas facilities. And, while natural gas vapors are odorless and nontoxic to breathe, diesel vapors contain toxics that are dangerous to ingest or breathe.
Wouldn't increases in natural gas prices make the buses extremely costly to run?
Historically, the price of natural gas has been lower than the price of diesel. Recent price spikes for natural gas cannot be seen as indicating a costly trend. The U.S. Energy Information Agency says that drilling for gas is at an all-time high, which will lead to greater supplies and lower prices of natural gas within this year.
