In California, Even Existing Emissions and Greenhouse Goals
Will Require Heavy Vehicle Advances, Likely Using Natural Gas
Existing clean air and greenhouse gas goals in California won’t be met without a new generation of technologies for heavy duty vehicles. The likelihood is that the same aggressive designs now being applied to make diesel acceptably clean will be applied to natural gas-fueled buses and trucks to make them even cleaner than they are today.
Those were some of the conclusions following last week’s Southern California Gas-sponsored Near-Zero-Emission Natural Gas Heavy-Duty Engines: Meeting California’s Air Quality and Climate Protection Goals webinar. Participants from the South Coast Air Quality Management District, Cummins Westport and the Southwest Research Institute discussed needs and potential solutions, and the challenges entailed in reducing NOx emissions by an order of magnitude from today’s limits.
“There’s a disconnect,” said webinar moderator Cliff Gladstein, between the rules governing heavy duty vehicles in California and the state’s clean air, low-carbon goals. “We will not meet attainment with any of the existing standards that are in place,” he said.
‘It’s the Trucks, Stupid’
And while “the light duty sector has mostly already been addressed,” trucks and buses have not. “Heavy duty diesel engines are the biggest source of pollution,” Gladstein said. Or, paraphrasing his mentor Carl Moyer, “It’s the trucks, stupid.”
Gladstein, himself one of the grand names of California air pollution reduction, is president of Fleets & Fuels publisher GNA – Santa Monica-based Gladstein, Neandross & Associates, which organized the SoCalGas webinar.
SCAQMD’s Matt Miyasoto agreed that truck and buses are the culprit. To reduce their impact, “Natural gas seems to be a good fit,” he said, with the “twofer” of emissions reduction and today’s potential for lower costs. There has to be “market pull” as well as regulatory “push,” he said.
Stephen Ptucha of Cummins Westport pointed out that as a manufacturer, he needs to design an engine that will sell. “Typically as the NOx emissions are lowered,” he said, “the fuel consumption is increased.” His firm’s stoichiometric ISL G and ISX12 G engines “are well positioned to form the basis for near-zero NOx emission products,” he said.
Hydrogen and Biomethane
SWRi senior research engineer Mark Walls of described work on an 11-liter engine from Doosan that’s been fitted with an advanced exhaust gas recirculation system. As near-zero emissions are approached, he said, cold starting become an issue, as catalysts don’t fully function until the system is warm. Using hydrogen to start a partial number of cylinders may help solve the cold-start issue, he said. The SWRi work will be shared with other engine manufacturers, he said.
Participants agreed that hydrogen mixed with natural gas may well improve the performance of the super-clean NGVs of the future, and observed too that biomethane will be of increasing importance to the reduction of well-to-wheel greenhouse gas emissions.
SoCalGas plans to post both a recording of the March 5 webinar and the four presentations. In addition, SoCalGas recently published a GNA-drafted report titled Pathways to Near-Zero-Emission Natural Gas Heavy Duty Vehicles (F&F, January 17).
GNA, Charlotte Medlock, 424-744-4482; mobile 909-801-4540; [email protected]
GNA, Melissa Wake, 949-852-7393; [email protected]; www.gladstein.org (direct link to Near-Zero report PDF)
Source: SoCalGas webinar with Fleets & Fuels follow-up