Abstract
The market demand for vehicles with reduced energy consumption, as well as increasingly stringent standards limiting CO2 emissions, are the focus of a large number of research works undertaken in the analysis of the energy consumption of cars in real operating conditions. Taking into account the growing share of hybrid drive units on the automotive market, the aim of the article is to analyse the total unit energy consumption of a car operating in real road conditions, equipped with an advanced hybrid drive system of the PHEV (plug-in hybrid electric vehicles) type. In this paper, special attention has been paid to the total unit energy consumption of a car resulting from the cooperation of the two independent power units, internal combustion and electric. The results obtained for the individual drive units were presented in the form of a new unit index of the car, which allows us to compare the consumption of energy obtained from fuel with the use of electricity supported from the car’s batteries, during journeys in real road conditions. The presented research results indicate a several-fold increase in the total unit energy consumption of a car powered by an internal combustion engine compared to an electric car. The values of the total unit energy consumption of the car in real road conditions for the internal combustion drive are within the range 1.25–2.95 (J/(kg·m)) in relation to the electric drive 0.27–1.1 (J/(kg·m)) in terms of instantaneous values. In terms of average values, the appropriate values for only the combustion engine are 1.54 (J/(kg·m)) and for the electric drive only are 0.45 (J/(kg·m)) which results in the internal combustion engine values being 3.4 times higher than the electric values. It is the combustion of fuel that causes the greatest increase in energy supplied from the drive unit to the car’s propulsion system in the TTW (tank to wheels) system. At the same time this component is responsible for energy losses and CO2 emissions to the environment. The results were analysed to identify the differences between the actual life cycle energy consumption of the hybrid powertrain and the WLTP (Worldwide Harmonized Light-Duty Test Procedure) homologation cycle.
Highlights
The motion of a car can be analysed as a consequence of certain energy transformations occurring in the drive unit of its drive system
The dominant power units in cars are power units based on ICE, where the basic transformation is related to the conversion of the chemical energy contained in the fuel into mechanical energy delivered to the drivetrain in order to overcome the resistance to the car’s motion [1]
It should be emphasized that all these groups of the listed components have a different impact on the total energy consumption of a car driving in dynamic road conditions
Summary
The motion of a car can be analysed as a consequence of certain energy transformations occurring in the drive unit of its drive system. The dominant power units in cars are power units based on ICE (internal combustion engines), where the basic transformation is related to the conversion of the chemical energy contained in the fuel into mechanical energy delivered to the drivetrain in order to overcome the resistance to the car’s motion [1]. It should be emphasized that all these groups of the listed components have a different impact on the total energy consumption of a car driving in dynamic road conditions. The works of Fontras et al [7] on fuel consumption and CO2 emissions in internal combustion propulsion systems resulting from factory data, in relation to the results obtained under laboratory and road tests, were reviewed. The most important components influencing the increased total energy consumption of the car are:
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
