Towards zero CO₂ emissions: Insights from EU vehicle on-board data

Area of Science:

• Environmental Science
• Automotive Engineering
• Transportation Policy

Background:

• Transport sector decarbonisation is a key EU policy objective.
• Accurate assessment of real-world (RW) CO2 emissions is crucial for effective policy monitoring.
• On-Board Fuel and Energy Consumption Monitoring (OBFCM) data offers detailed insights into vehicle performance.

Purpose of the Study:

• To develop and apply a data-driven methodology for assessing RW CO2 emissions from passenger cars in the EU.
• To identify key factors influencing RW CO2 emissions across different vehicle technologies.
• To estimate total RW CO2 emissions for newly registered vehicles in the EU.

Main Methods:

• Analysis of OBFCM data from 7.7 million passenger cars registered in the EU (2021-2023).
• Application of multivariable regression models to determine emission factors for various powertrain/fuel types.
• Estimation of fleet-wide RW CO2 emissions based on identified emission factors and vehicle data.

Main Results:

• Vehicle mass and engine power are primary drivers for Internal Combustion Engine Vehicles (ICEVs) and Hybrid Electric Vehicles (HEVs).
• Electric driving share is the dominant factor for Plug-in Hybrid Electric Vehicles (PHEVs).
• Estimated average in-use EU fleet emissions range from 131 g/km (petrol PHEVs) to 190 g/km (diesel HEVs).

Conclusions:

• The developed methodology provides a robust empirical basis for quantifying RW CO2 emissions.
• PHEVs demonstrate the highest CO2 reduction potential among analyzed vehicle types.
• Findings support the monitoring of EU transport decarbonisation policies and inform future strategies.