Current vehicle emission standards will not mitigate climate change or improve air quality

Area of Science:

• Environmental Science
• Automotive Engineering
• Atmospheric Chemistry

Background:

• The 2016 UK Department of Transport vehicle emissions testing programme was initiated following the Volkswagen emissions scandal.
• Previous testing identified significant discrepancies between laboratory and real-world emissions for diesel passenger vehicles (Euro 5 and Euro 6 standards).
• Controlling real-world vehicle emissions remains a significant environmental challenge.

Purpose of the Study:

• To present findings on emissions discrepancies in a large fleet of diesel vehicles.
• To introduce a novel Real-Life Emissions methodology to enhance current Real Driving Emissions standards.
• To address critical issues in vehicle emissions testing and climate change mitigation strategies.

Main Methods:

• Conducted a comprehensive vehicle emissions testing programme on a large fleet of Euro 5 and Euro 6 diesel passenger vehicles.
• Analyzed nitrogen oxides (NOx) emissions in relation to exhaust gas recirculation (EGR) mismanagement.
• Developed and introduced a new Real-Life Emissions methodology for improved real-world emissions assessment.

Main Results:

• Identified significant discrepancies between real-world and in-lab testing for NOx and CO2 emissions.
• Confirmed that NOx emissions are altered due to exhaust gas recirculation mismanagement.
• Discovered a concerning divergence between NOx improvements and CO2 deterioration in real-world conditions.

Conclusions:

• Current vehicle emissions testing standards, even post-Volkswagen scandal, are insufficient to capture real-world emissions accurately.
• The proposed Real-Life Emissions methodology offers a more accurate assessment of vehicle environmental impact.
• Improved emissions testing is crucial for effective climate change mitigation and air quality enhancement.