California Air Resources Board
Reverses, Approves Green Diesel

By Wendy Broffman
STN Associate Editor

SACRAMENTO, Calif.-There's a saying that goes, "If you're not part of the solution, you're part of the problem." In California, Governor Gray Davis has approved a $50 million allocation plan to help solve the hazard that school bus emissions pose to children's health. Diesel buses have been targeted as part of the problem, but the efforts of at least one engine manufacturer have turned a problem into a solution.

Plan Amends Earlier Proposal
On December 7, the California Air Resources Board recognized "green diesel" as part of the clean air solution, allowing $12.5 million of the $50-million budget for the purchase of OEM low-sulfur "green" diesel school bus engines, and another $12.5 million to retrofit old buses with low emission diesel technology. The remaining $25 million is allocated to the purchase of new natural gas buses. The final plan amends the Board's earlier proposal that excluded the new diesel technology from the spending program aimed at protecting children from cancer-causing emissions. Under the plan proposed in September, only natural gas buses that cost $25,000 more than their new diesel alternatives were to be subsidized. The decision is a victory for the health of all Californians, especially children, said Tom Trueblood, manager of public affairs for International Truck and Engine Corp.

Two Categories Created
In it's final guidelines; the Board has created two categories for OEM school buses. Natural gas buses must be certified to ARB's optional, reduced-emission NOx standards (2.5 g/bhp-hr or lower) and a PM emission level of 0.03 g/bhp-hr; and low sulfur diesel buses will be required to meet 3 grams of NOx and a 0.01 g/bhp-hr PM level. International is on target to bring to market in mid-2001 a new school bus fueled by ultra-low sulfur fuel, and equipped with a catalyzed particulate trap and a special low-NOx engine calibration certified to meet the latter, Trueblood told the Board.

Although green diesel technology does not meet ARB's optional, reduced-emission NOx standards, the Board called its inclusion "an intermediate step in the introduction of lower-emission diesel engine technology," and attributed its decision to recent advances in diesel technology, plus economic benefits.

Ruling Maintains Balance
We made our decision based on several points," said Jerry Martin, spokesman for CARB. "One is the lack of infrastructure in many parts of the state. In those same areas where there is heavy snowfall and mountainous roads, CNG doesn't have the power of diesel.

Third, is cost! What seems to escape some people is that school boards and school bus companies don't have public funding and the federal backing that public transit has. Even with this program, where 75% of the purchases will be subsidized, the school board or bus company has to come up with the remaining 25%."

Because clean diesel buses are much cheaper than their CNG alternatives, school districts can retire more older buses by replacing them with OEM's using the new diesel technology.

Martin added that though CARB would like to see the cleanest emissions vehicles on the road, "we try to maintain a balance. There are only a few companies that make school buses. International happens to be somewhat cleaner than its competitors on NOx and cleaner than even CNG on PM. ARB is the only government agency in the U.S. to identify PM as a toxic air contaminate. We are keenly aware of the health threat from diesel. But there have been some questions about CNG particulate as well. A definitive answer as to any health risks from CNG particulate may still be years off," Martin concluded.

Back to Business
The issue has been the focus of lobbying and demonstrations by natural gas and clean diesel proponents. International officials, in efforts to be included in ARB's spending plan, demonstrated green diesel technology at locations around California. Natural gas advocates, who wanted only alternative fuel buses to be eligible for funding, hoped to dissuade the ARB's decision before a final ruling was made by enlisting school children to don gas masks. Now that the Board has made its final ruling, school districts have options and advocates of both sides can attend to other matters of consequence

Source: Reprinted from School Transportation News, January, 2001. All rights reserved.