Indirect methodologies to estimate energy use in vehicles: Application to battery electric vehicles

• Development of method based on real-world measurement of electric vehicles.
• Assessment of Vehicle Specific Power for electric vehicles, including quadricycles.
• Innovative indirect non-intrusive methodology to estimate modal energy consumption.
• Deviations between on-road measurements and estimates below 10%.

Considering electric mobility as a viable alternative to conventional technologies, it is essential to characterize electric vehicles in terms of their real-world energy use. The objective of this work was to characterize in detail the real-world energy use of battery electric vehicles. An innovative method was developed through a calibration procedure using a group of three electric quadricycles, which were measured in real world on-road conditions for several trips by collecting 1 Hz data on vehicle dynamics (speed, acceleration and slope) and energy usage (measured directly at the battery terminals). Using this dataset, and through the adaptation of the vehicle specific power approach for quadricycles, it was possible to estimate electricity consumption with an absolute error between 1.4% and 4.5%. Due to the difficulties and risks associated to direct battery measurements of voltage and current of commercially available light-duty battery electric vehicles, this methodology was expanded and validated to this vehicle class in order to define the second-by-second electricity consumption as a function of the vehicle dynamics, based only on global recharging data per trip. The results obtained for two light-duty battery electric vehicles present similar accuracy and precision when compared to experimental results obtained for the electric quadricycles, with absolute deviations between 5.2% and 7.3%. The development of indirect methodologies to estimate the real-world on-road battery electric vehicle energy use in a prompt and simple way constitutes a powerful tool to evaluate the performance of these vehicles on any real-world trip.