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Clean diesel technology and ozone standards

Hydrocarbon Engineering,

A US EPA hearing has been told that the clean air benefits from new technology clean diesel engines and the importance of efforts to accelerate the modernising or upgrading of existing vehicles and equipment will be important to meet any future clean air standards. The comments were made by Allen Schaeffer, Executive Director of the Diesel Technology Forum at the first of three hearings conducted by the EPA on the proposed updates to the national air quality standards for ground level ozone.

Schaeffer did not comment on the proposed changes but did highlight how the cooperative working relationship between the EPA, national environmental and health organisations and manufacturers had resulted in significant improvements to diesel efficiency and reduced emissions.

Schaeffer said, “diesel engines are a declining contributor to the national inventory of nitrogen oxides, a key ozone precursor. The increasing utilisation of new technology clean diesel engines will play the most important role in assuring continued progress toward both clean air and climate objectives. And according to the Advanced Collaborative Emissions Study (ACES) research cosponsored by EPA and released this week by the Health Effects Institute, new technology diesel engines near zero emissions performance was confirmed, as was the finding of no significant health effects in lab animals over lifetime exposure. The diesel industry is building on these clean air accomplishments and now increasingly focused on producing near zero emissions technology that also is more efficient and has lower greenhouse gas emissions as well.”

Making progress

Schaeffer pointed out that the impressive NOx emissions reductions from diesel accrue from over a decade of collaboration between the leaders in clean diesel technology and the EPA in establishing a regulatory pathway that brought about the introduction of these clean diesel engines in on and off road applications. Schaeffer said, “since 2000, diesel engine manufacturers have been working to meet the challenge of virtually eliminating emissions from diesel engines. Today, manufacturers have met that challenge. First along the pathway were strict NOx emissions standards promulgated for the heavy duty on road fleet beginning in model year 2007 and further tightened for model year 2010.”

Schaeffer continued, “as of 2013, we estimate that these clean diesel heavy duty vehicles have reduced NOx by 1 million t nationwide. In some regions and localities, the NOx emission reduction from clean diesel trucks has been even more substantial. To achieve these very low levels of nitrogen oxide emissions, engine manufacturers and emissions control technology manufacturers have invested billions of dollars to reduce the formation of nitrogen oxide emissions through controlling of the combustion process itself as well as the use of emissions control technology such as selective catalytic reduction systems (SCR).”

Edited from press release by Claira Lloyd

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