For car enthusiasts and potential owners, understanding how vehicles are tested for fuel consumption and emissions is increasingly important, especially when considering high-performance SUVs like the Ferrari Suv, the Purosangue. Standardized laboratory tests are crucial for providing comparable and reproducible data across different models. These tests, based on specific driving cycles, allow consumers to make informed decisions. Two key protocols are the New European Driving Cycle (NEDC) and the Worldwide harmonised Light-duty vehicle Test Procedure (WLTP). Understanding the difference between these is key to interpreting vehicle specifications.
The New European Driving Cycle (NEDC) was the established European standard for measuring fuel consumption and emissions for passenger cars and light commercial vehicles for a long time. Originating in 1970 with an urban driving simulation, it was expanded in 1992 to include an extra-urban phase and further refined in 1997 for measuring consumption and CO2 emissions. However, the NEDC cycle’s composition became outdated when compared to modern driving habits and road conditions. With an average speed of just 34 km/h and a maximum speed of only 120 km/h, and modest accelerations, NEDC began to be seen as less representative of real-world driving, particularly for high-performance vehicles.
Alt text: Comparison of NEDC and WLTP driving cycles highlighting the differences in speed profiles, reflecting on emission testing for vehicles like Ferrari SUV.
The Worldwide harmonised Light-duty vehicle Test Procedure (WLTP) was introduced to address the shortcomings of NEDC. First implemented in Europe on September 1, 2017, WLTP utilizes new Worldwide harmonised Light-duty vehicle Test Cycles (WLTC) to assess fuel consumption, CO2, and pollutant emissions. The primary goal of WLTP is to offer consumers more realistic data that better reflects everyday vehicle use. The WLTP procedure incorporates a more dynamic driving profile characterized by more significant acceleration and deceleration phases. The maximum speed is increased to 131.3 km/h, the average speed is raised to 46.5 km/h, and the total cycle duration is extended to 30 minutes. The distance covered in the test is also doubled to 23.25 kilometers.
The WLTP test is composed of four parts, categorized by speed: Low (up to 56.5 km/h), Medium (up to 76.6 km/h), High (up to 97.4 km/h), and Extra-high (up to 131.3 km/h). These segments are designed to simulate a range of driving conditions, from urban and suburban environments to extra-urban roads and motorways. Crucially, WLTP also considers vehicle-specific optional equipment that impacts aerodynamics, rolling resistance, and overall vehicle mass. This results in a CO2 emission value that is more closely aligned with the individual vehicle’s configuration. For a vehicle like the Ferrari SUV, which offers various customization options, WLTP provides a more accurate reflection of real-world performance and emissions compared to the older NEDC standard. This detailed testing regime ensures that consumers get a clearer picture of what to expect in terms of fuel efficiency and environmental impact from their chosen vehicle.
