Today’s testing standards for measuring the energy consumption and range of electric vehicles (EVs) are based on techniques initially developed for use with internal combustion engine (ICE) vehicles.
How it works: the vehicle is run on a dynamometer, its energy consumption is measured, and the miles (or kilometers) per unit of energy and range are calculated. While the basic testing technique is common worldwide, the actual requirements differ.
This FAQ compares the Environmental Protection Agency’s (EPA’s) Federal Test Procedure 75 (FTP-75) used in the US with the China Light-duty Passenger Car Test Cycle (CLTC-P), and the European Worldwide Harmonized Light Vehicle Test Procedure (WLTP). It closes by getting “under the hood” of the WLTP, CLTC-P, and FTP-75 standards and looking at some of their components.
Some common elements of these standards are defined acceleration, deceleration, and cruising distances and times. For example, the CLTC-P is implemented over 1800 seconds and covers 14.45 km with a maximum speed of 114 kph and maximum accelerations and decelerations of 1.47 m/s2.
The WLTP was developed in 2017 and is an update to the New European Driving Cycle (NEDC) developed in the 1980s. NEDC consists of two components, NEDC1 (urban) and NEDC2 (extra urban) that have been combined in the WLTP (Figure 1). Another change is that the newer tests are longer, 1,847 seconds for the FYP-75 Urban Dynamometer Driving Schedule (UDDS) and 1,800 seconds for the WLTP and CLTC-P, while the NEDC was 1,180 seconds.
Testing values and procedures for older tests like the NEDC were developed using theoretical driving profiles. The new standards are intended to be more representative of actual conditions. That accounts for much of the variations. The FTP-75 models U.S. driving patterns, the CLTC-P is based on actual driving patterns experienced in China, and the WLTP was developed using driving data from several global regions. The driving patterns in different regions resulted in the development of WLTB vehicle classes.

Figure 1. Distance comparison for international testing standards. (Image: EDP Sciences)
WLTP vehicle classes
The WLTP includes three different driving cycles based on three vehicle classes. The classes represent the vehicle’s power-to-mass (PMR) ratio and maximum speed. For an EV, the PMR uses the rated power in W and the curb weight in kg.
The three classes include:
- With a PMR of >34, Class 3 represents the types of vehicles driven in Europe and Japan.
- With a PMR less than or equal to 34 and greater than 22, Class 2 represents the types of vehicles driven in India and low-power vehicles driven in Japan and Europe.
- With a PMR of 22 or less, Class 1 represents the vehicles driven in India.
CLTC-P testing segments
The CLTC-P in broken down into three segments:
- A low-speed phase, CLTC-P1 for 674 seconds
- A medium-speed phase, CLTC-P2 for 693 seconds
- A high-speed phase, CLTC-P3 for 433 seconds (Table 1).
The three phases include 11 short trips and 12 idle periods. The average speed is 28.96 kph, the maximum speed is 114.0 kph, and the test consists of idling for 22.11% of the time.

Table 1. The CLTC-P test cycle includes three segments for low-speed, medium-speed and high-speed driving simulations. (Table: EDP Sciences)
FTP-75 components
The basic FTP-75 includes two sections: the city driving UDDS cycle for 1874 seconds and the Highway Fuel Economy Test (HWFET) cycle for 765 seconds (Figure 2). Like the updated CLTC-P and WLTP, FTP-75 has been correlated with real driving experiences.

Figure 2. UDDS cycle (orange) and HWFET cycle (blue) comparison of speed versus duration. (Image: Electric Vehicle Knowledge Exchange)
In addition to the UDDS and HWFET cycles, the EPA has defined three additional test cycles. Manufacturers can choose to use basic two-cycle testing or extended five-cycle testing.
These cycles include:
- US06 is a high acceleration and aggressive driving cycle that simulates driving on rural roads and freeways at higher speeds.
- SC03 simulates using the air conditioner while driving in hot weather.
- Cold CO2 is administered at 20° F (-7° C) instead of 75° F (24° C), which is used for the other test cycles and simulates vehicle operation using the heater during cold weather.
Summary
Measuring the energy consumption and estimating the range of EVs involves running the vehicles on a dynamometer under specific test conditions. Various testing regimes are based on actual driving conditions in areas like the U.S., China, Europe, Japan, and India. The tests provide a standard metric for comparing EV performance and are not absolute measurements.
References
- CLTC range testing, Electric Vehicle Knowledge Exchange
- Comparative Analysis of China Light-duty Vehicle Test cycle for Passenger Car and Other Typical Driving Cycles, EDP Sciences
- EPA range testing, Electric Vehicle Knowledge Exchange
- FTP-75, Wikipedia
- International Light-Duty Worldwide Harmonized Light Vehicles Tests Procedure, Transport Policy
- WLTP Facts
Images
- Figure 1, EDP Sciences, Page 3, Figure 5
- Figure 2, Electric Vehicle Knowledge Exchange, half-way down the page
- Table 1, EDP Sciences, Table 1, Page 1
Filed Under: FAQs