Education Moves Forward to an Idle Stop

Approximately 25 million students rely on school bus transportation every day for a safe commute to and from school. Parents have entrusted the school bus industry to provide transportation for their children and to protect their well being. School buses have an exceptional safety record for transporting students without physical harm, but does anyone think about the health of their son or daughter when riding on a school bus? It is important to discuss the possible health risks of diesel emissions and the new technologies that have been developed to reduce harmful emissions, fuel costs, and dependence on foreign oil.

Approximately 500,000 buses shuttle students daily to and from school, with a child spending approximately an hour on the roads each day. With the average school year lasting 180 days, children are spending a total of 180 hours riding on a school bus each year. During the years from K-12, a student will spend nearly 2,500 hours riding on a school bus. This total does not include field trips, sporting events, band trips, etc. This equates to long-term exposure to diesel emissions, which have caused an increase in asthma, bronchitis, and other respiratory symptoms.

Some of the most harmful emissions produced from diesel fuel are particulate matter (PM), which is very small in size but can be seen as black smoke from the exhaust from the tailpipe. Diesel fuel in the United States has undergone major improvements that greatly reduce the risks associated with diesel emissions. The U.S. Environmental Protection Agency (EPA) has mandated the use of Ultra Low Sulfur Diesel fuel, which reduces emissions, for 2007.

The use of biodiesel also reduces the harmful emissions of diesel fuel. Biodiesel is a renewable motor fuel for use in diesel engines and is produced from agricultural products, such as soybeans, rape seed (canola), or other vegetable and animal fats. It is commonly used as a blend with petrol diesel fuel in a 2% (B2) or 5% (B5) blend but also may be run as 100% fuel in some applications. The use of biodiesel blends is a cost-effective way to reduce harmful emissions because it can be run in a diesel engine with little or no modifications.

Hybrid electric drive systems are the latest technology to be introduced into school buses to help reduce emissions and dependency on foreign oil. A hybrid is a combination of an internal combustion engine (ICE), electric drive motor/generator, and a battery storage system. There are currently several variations of hybrids available in automobiles, and the system being used in school buses is a parallel drive developed by Enova Systems and IC Corporation of Navistar. A parallel hybrid drive allows both the ICE and electric motor to propel the bus. The hybrid bus also incorporates the use of plug-in hybrid technology, which allows the bus to be plugged into the electrical grid to charge the batteries, giving it the ability to travel longer distances on electric only mode.

The EPA has introduced a National Idle Reduction Campaign which is designed to:

• Provide an opportunity for pupil transportation managers, bus drivers, teachers, and children to learn about air quality and diesel emissions
• Recognize the positive contribution being made by school bus drivers
• Promote idle-reduction as an easy way to save money by not wasting fuel, reducing wear and tear on engines, protecting drivers' health and the health of children, and improving air quality.

The new hybrid technology in school buses demonstrates the benefits of idle stop. A hybrid will shut off the engine while the bus is not in motion. This option allows for a great reduction in emissions and increases fuel economy. The average school bus can have an annual savings of 45 gallons and more than $100 dollars a year. As we look at the amount of buses being used throughout the country, that is 22.5 billion gallons of fuel and 50 billion dollars a year in savings without considering the use of electric only mode. The clean-burning technology of a hybrid is another benefit of using hybrid school buses. The combination of electric only mode and reduced fuel usage dramatically reduces the emissions of a school bus, creating a healthier environment for our children. Not only will the hybrid technology help with the environment, we can also use it to educate our youth on the technologies of today and encourage them to consider alternative fuel and advanced technology vehicles as they become the next generation of consumers.