MJB&A Evaluates Solutions to High “off-cycle” NOx Emissions from European Heavy Trucks

On behalf of the International Council on Clean Transportation (ICCT), MJB&A helped ICCT staff prepare a white paper to identify technical and policy options to reduce high “off-cycle” emissions of nitrogen oxides (NOx) from heavy-duty trucks certified to Euro IV and Euro V emission standards.

Despite meeting these current, more stringent, regulatory standards for exhaust emissions many of these trucks equipped with selective catalytic reduction (SCR) systems have significantly elevated NOx emissions during in-use urban driving. In some cases, actual in-use urban emission levels may be as high as or higher than those from much older vehicles with engines certified to more lenient emission standards.

These high “off-cycle” NOx emissions threaten efforts to improve ambient air quality in many European cities, as well as in developing countries such as Brazil, India, and China, which are beginning to implement standards for new trucks and buses that are based on the European regulation.

The report details the technical reasons for high off-cycle emissions from Euro IV/V heavy vehicles, as well as their root cause: deficiencies in the Euro IV/V type-approval process. It describes a range of technical options available to improve in-use performance, and makes specific recommendations for both Europe and developing countries.

The full report can be accessed here.