How much energy does a car need on the road?

• Published in: Applied energy Vol. 256; p. 113948
• Main Authors: Küng, Lukas, Bütler, Thomas, Georges, Gil, Boulouchos, Konstantinos
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15-12-2019
• Subjects: Chassis dynamometer; Field monitoring; Fuel consumption; Non-propulsive load; Passenger cars; Real-world energy demand; Passenger cars; AC; CADC; FTP; Real-world energy demand; Field monitoring; HTS; Fuel consumption; ICCT; GPS; WLTC; BAFU; NEDC; ECU; EPA; Non-propulsive load; EMPA; WLTP; Chassis dynamometer; PEMS; PTC
• ISSN: 0306-2619; 1872-9118
• DOI: 10.1016/j.apenergy.2019.113948

•Real-world energy demand model for alternative and conventional cars.•Widely applicable, as input data on car trip are average velocity and mean slope.•Impact of different driving styles and usage of auxiliary devices incorporated.•Correlations based on dynamometer measurements and field test.
A car often requires more energy when driven in daily operation than indicated by the manufacturer. This paper presents a model to derive this real-world energy demand for a passenger car, based on a few widely available input data on vehicle operation. The approach works for conventional and alternative propulsion technologies. The underlying data stem from an extensive Swiss chassis dynamometer and on-road measurement campaign, which lasted for more than a year. The test fleet consisted of a compressed natural gas, gasoline hybrid, gasoline plug-in hybrid, fuel cell electric, and a battery-electric vehicle. The derived model adjusts the propulsive power demand within the legislative WLTP cycle for class 3b vehicles to a road mission by incorporating effects of traffic, driving styles, and topography. It additionally accounts for load from auxiliary devices. The approach works with input data from a household travel survey or traffic flow simulation and can serve as a tool to everyone who needs to estimate the average on-road energy demand of any passenger car or a fleet of them, rather than their type-approval values. Tested on a compact-sized vehicle, the approach estimates a mean discrepancy in real-world energy demand to WLTP type-approval values for Switzerland of about 22% for conventional cars. Furthermore, we can show similar gaps for hybrid technologies of around 30% and for battery-electric cars of 25%.