Bill Would Phase-Out Most Diesel Emissions in California

The bill is directed at the medium and heavy-duty trucking industry, which, along with buses, account for 90 percent of the state's toxic diesel exhaust. Diesel emissions would need to be reduced by 80 percent by 2050. Will electric trucks be ready?

3 minute read

March 21, 2019, 12:00 PM PDT

By Irvin Dawid


California Freeway

Karin Hildebrand Lau / Shutterstock

On March 7, State Sen. Nancy Skinner, D-Berkeley, introduced Senate Bill 44, dubbed “Ditching Dirty Diesel,” which is "designed to phase out, over time, the use of polluting, diesel-fueled medium- and heavy-duty trucks and buses in California and to speed up the transition to cleaner vehicle technologies and fuels, including zero emission vehicles (ZEVs)," according to her office. 

“It’s no secret that medium- and heavy-duty trucks and buses are significant sources of lung-damaging particulate matter,” Skinner said. “But what is less known is that diesel-fueled trucks and buses produce nearly one-quarter of GHG emissions from California’s transportation sector.” 

Since 1998, the California Air Resources Board has recognized diesel particulate matter as a toxic air contaminant based on the relationship between diesel exhaust and lung cancer.

SB 44 "would direct the California Air Resources Board to require a 40 percent reduction in diesel emissions by 2030 and an 80 percent reduction by 2050, cuts that experts say would not be possible without a major overhaul of the trucking industry," writes Peter Fimrite, science reporter for the San Francisco Chronicle.

SB44 would also designate an unspecified amount of money from the state’s Greenhouse Gas Reduction Fund [aka cap-and-trade auction revenues] for the development of alternate fuels and technology.

According to one source of this correspondent, that could be one of the main intentions of the bill: to tap into the Low Carbon Transportation Investments and Air Quality Improvement Program to provide more funds for heavy-duty truck electrification projects. An SB 44 fact sheet [pdf] indicates that the bill calls for the appropriation of "funds through 2025 to support the purchase of clean medium and heavy-duty vehicles by businesses across California."

In regards to truck electrification, readers may wish to listen to KPBS Midday Edition (NPR Affiliate in San Diego), "How Soon Will Big Rigs Go Electric In California?" with environment reporter Joshua Emerson Smith of The San Diego Union-Tribune on Feb. 19.

Heavy-duty diesel trucks emit 70 percent of the most toxic air pollution from on-road vehicles in California. And a lot of that pollution is centered in lower-income neighborhoods. So there's an effort underway in San Diego and at loading docks across the state to switch to cleaner equipment.

"Diesel engines are more than 97 percent cleaner today than they were in 1990," Smith states in responce to one of host Maureen Cavanaugh's questions.

"Now the race is on to roll out the first battery-powered big rigs — a move aimed at not only curbing greenhouse gases but harmful air pollution that overwhelmingly impacts low-income neighborhoods from Oakland to Long Beach to Barrio Logan, reports Smith in his Feb. 18 article, "How fast can California switch from diesel-burning freight trucks to electric big rigs?" in the article that prompted the interview.

"Skinner’s bill follows a ruling in December by the California Air Resources Board requiring all transit agencies to make their fleets entirely emission-free within two decades," adds Fimrite of the Chronicle. "The rules prohibit the purchase of any new gas- or diesel-powered public transit buses by 2029 and require all buses to be emission-free by 2040."

In a related opinion published Feb. 4 in the Chronicle, Rocky Rushing, a senior policy advocate for the Coalition for Clean Air, writes in support of new legislation to establish a smog certification program for heavy-duty diesel trucks.

State Sen. Connie Leyva, D-Chino (San Bernardino County), introduced SB 210, which would require owners of heavy-duty diesel trucks to certify they meet the state’s emission standards.

Related in Planetizen:

Hat tip to Earthjustice's Right To Zero March 15 newsletter.

Friday, March 8, 2019 in San Francisco Chronicle

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