You might not know that the New European Driving Cycle (NEDC), introduced in the late 1980s, was originally made to standardize emissions and fuel economy testing across Europe.
While it aimed to create a uniform standard, the NEDC has been heavily criticized for not accurately reflecting real-world driving conditions.
This gap has led to overly optimistic fuel economy numbers and not enough emissions reductions, especially for diesel vehicles.
So, what exactly went wrong, and how has the industry responded to these issues?
Historical Context
The New European Driving Cycle (NEDC), created in the late 1980s, was designed to standardize emissions and fuel economy tests across Europe.
It included an Urban Driving Cycle (UDC) and an Extra-Urban Driving Cycle (EUDC) and moved from UNECE regulation 15 to 83, making the rules stricter.
However, as hybrid cars became more common, the NEDC didn’t reflect real-world driving well, so the WLTP was adopted instead.
Testing Procedures
When performing the New European Driving Cycle (NEDC) test, begin with a cold vehicle at temperatures between 20-30°C, making sure it has been sitting for 6 hours before starting.
The test includes:
- Urban Driving Cycle: Repeating the ECE-15 test four times.
- Extra-Urban Driving Cycle: Testing at higher speeds.
- Constant Volume Sampling: Measuring emissions.
- Maximum Speeds: 50 km/h for urban, 120 km/h for extra-urban.
- Total Duration: 1180 seconds.
Criticisms and Issues
Even though it’s widely used, the New European Driving Cycle (NEDC) has been heavily criticized for not reflecting real-world driving conditions accurately.
The NEDC’s unrealistic acceleration and fixed speeds make fuel economy numbers look better than they really are, allowing for “cycle beating.”
Diesel vehicles show little improvement in reducing emissions, which hurts public health.
Because of these issues, the WLTP was created to provide more accurate test results and better mimic how people actually drive today.
Future Directions
Looking ahead to future testing methods, the car industry is set to use more accurate and realistic approaches.
Moving from the NEDC to the WLTP focuses on:
- Emissions by using real-world data
- Fuel consumption in different driving situations
- Including new vehicle technologies
- Better energy efficiency measures
- Tougher compliance with environmental rules
These changes ensure a thorough evaluation that meets new standards.