California Diesel Incentive Programs

California has funded programs that provide incentives for manufacturers and operators of diesel vehicles and equipment to clean up pollution from the state’s school buses, transit buses, garbage trucks, and other heavy-duty diesel engines. These programs have proven to be an enormous, cost-effective success in reducing air pollution, protecting public health, and providing children with safe, healthy transportation to school.  While regulatory measures continue to be the backbone of efforts to meet health protective air quality standards, these incentive programs encourage early emission reductions, expand the market for new emission control technologies, and achieve reductions from sources otherwise not captured by clean air regulations.

Fortunately, the governor and state legislature, as well as California voters realize the importance of these programs and have supported efforts to fund these programs.  In 2004, the legislature passed and the governor signed legislation (AB923) to fund the Moyer Program at $140 million per year for 10 years.  In 2006, California voters approved Proposition 1B, which set aside $1 billion for funding projects to reduce diesel emissions from goods movement activities, and an additional $200 million to retrofit and replace the state's aging school bus fleet.  We applaud these efforts and urge both the governor and the legislature to continue to work together to increase funding to reduce harmful diesel pollution.

Moyer Program

In 1999, California created the Moyer Program to reduce smog-forming Nitrogen Oxides (NOx) from diesel engines and replace diesel with cleaner alternatives such as natural gas and electricity. Nitrogen oxides and hydrocarbons can react in the presence of sunlight to form ozone, or smog. Hospital admissions escalate on smoggy days, particularly with asthma patients. Children, the elderly, and people with pre-existing respiratory and cardiovascular disease may be most sensitive to the harmful impacts of smog. To directly combat these side effects of smog, the program helps offset the incremental costs of purchasing or retrofitting a cleaner engine. In order to ensure funding for the most effectual replacement or retrofit initiatives, each project must meet a specific cost-effectiveness level.

For the first six years, UCS estimates the Moyer Program has reduced smog-forming NOx emissions by about 6,000 tons per year. Although the focus of the program is NOx, significant Particulate Matter (PM), or direct tailpipe diesel soot emissions, reduction benefits have been also been achieved. The first six years of funding (1999-2004) have resulted in the prevention of an estimated 240 to 350 premature deaths. Through 2004, the Moyer Program had replaced nearly 4,600 older diesel engines with new, cleaner diesel engines primarily in marine vessels, off-road equipment, and agricultural irrigation pumps. The Moyer Program had also funded more than 1,700 alternatively fueled vehicles, especially transit buses and refuse trucks.

UCS performed a cost benefit analysis of the Moyer Program and found that the program has achieved health benefits valued ten times greater than the investment. UCS estimates an investment of two cents in the Moyer Program for every Californian will result in one less premature death from diesel pollution. The program could save hundreds of lives over the next two decades if sufficient funding is provided.

See UCS's Sick of Soot report for a complete cost-benefit analysis of the Moyer Program and the potential for future public health benefits and economic savings.

Low emission school bus program

With the nation’s third largest school bus fleet, California maintains some of the oldest and dirtiest school buses on the road. In the UCS 2006 study of tailpipe pollution, California’s school buses received the poorest score in the country for smog-forming emissions and scored a “C” for toxic soot.¹ Almost half of California’s 30,000 school buses are more than a decade old. As a result, the average school bus in California emits two times the amount of soot as a big rig per mile. In addition, approximately 300 of California’s public school buses were built before 1977, predating safety standards for passenger seating and crash protection, rollover protection, body joint strength, and fuel system integrity. These buses are safety hazards as well as major polluters.

The health implications of having an outdated and dirty school bus fleet are significant. CARB released a new study in October 2003 that found that children riding in conventional diesel school buses are exposed to two to five times more air pollution than those riding in cleaner natural gas powered buses or low emission diesel buses.² The researchers concluded that children riding these buses for 13 school years would have a four percent higher risk of contracting cancer from diesel exhaust, as well as higher risks for respiratory ailments and hospitalizations for asthma.

To address these problems, CARB started the Lower Emission School Bus Program in December 2000. This incentive program provides funds for replacing older buses, especially those built before 1977, with new, cleaner compressed natural gas (CNG) or diesel buses. The program also provides funding for advanced retrofit equipment to reduce soot.  Through the state program and with help from EPA's Clean School Bus Program, about 11 percent of the fleet has particulate traps and the state has about 1400 CNG buses in operation.  The recent approval of Proposition 1B in November 2006 will provide $200 million in additional funding for the program.  This funding should be targeted at completing the replacement of pre-1977 buses and retrofitting newer buses with diesel particulate filters.

(1) UCS, School Bus Pollution Report Card Grading the States, MA May 2006
(2) CARB, Characterizing the Range of Children's Pollutant Exposure during School Bus Commutes, June 2003

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