Report: Cleaner Diesel Technology Improving Air Quality
Future Technology to Offer Even More Air Quality Benefits
Sacramento, CA — As a result of cleaner fuels and new low emissions technologies, emissions from on and off-road diesel vehicles have dropped considerably and are expected to continue decreasing in California through the year 2020, according to a report prepared by Sierra Research, Inc., for the Diesel Technology Forum (DTF).
The report, "The Contribution of Diesel Engines to Emissions of Reactive Organic Gases (ROG), Oxides of Nitrogen (NOx) and Particulate Matter (PM) in California: Past, Present and Future," examined emissions data from California as a whole as well as the South Coast, San Joaquin Valley and San Francisco Bay Area Air Basins from 1975 through 2020.
"The key finding in this report is that the continuous improvements made in diesel engines and fuels over the last 30 years have delivered significant clean air benefits for Californians, and the new clean diesel technologies and fuels now being developed for 2007 and 2010 will deliver even more substantial benefits to California's air quality," said Allen Schaeffer, DTF executive director.
Schaeffer added that it is the combination of cleaner fuels, new advanced engine technologies and retrofit devices like particulate traps that have helped slash diesel emissions from a decade ago, and will keep cutting emissions to provide cleaner air in the future.
According to the report, statewide emissions of NOx have been steadily declining since 1990, and as new standards take effect the contribution from on and off-road diesel engines "will diminish considerably between now and 2020." NOx is a key ingredient in the formation of smog and, like PM, has been the subject of intense scrutiny from regulators.
Specifically, statewide on-road NOx emissions have dropped by 30 percent since 1990, and are expected to drop another 64 percent between now and 2020. Likewise, off-road NOx emissions have dropped by 27 percent since 1990 and will drop another 31 percent by 2020.
As for PM, the report says diesel engines currently account for only 10 percent of statewide PM emissions and will account for a diminishing fraction of as new standards take effect. By 2020, statewide on and off-road PM emissions will be slashed to just 29 percent and 43 percent, respectively, of their 1990 levels.
"There's no question that California's aggressive policies to reduce diesel emissions from both new and existing vehicles and equipment have significantly challenged the diesel industry," Schaeffer says. "This analysis affirms that industry has stepped up and met those challenges, and the results are evident in the drops in diesel emissions levels."
Schaeffer credits much of the industry's success to its efforts at attacking the emissions challenge on both ends.
"Not only has the industry pushed the envelope on what new technology can achieve, we are also focused on applying new technology to upgrading and modernizing the existing fleet," Schaeffer says. "We're seeing the results in the air today, and tomorrow's diesels will bring us even closer to zero emissions."
The Sierra Research report is based primarily on emissions inventory data from the California Air Resources Board. The report also accounts for changes in emissions levels as a result of currently promulgated federal and state regulations through 2020. In addition to NOx and PM, the report also examined ROG inventories statewide and in all three air basins. In short, the report found that diesel emissions have and will continue to account for a negligible portion of overall ROG emissions.
A complete copy of the report is available at http://www.dieselforum.org.
SOURCE: Diesel Technology Forum