Evaluation of plug-in hybrid vehicles in real-world conditions by simulation and their contribution to mitigating greenhouse gas emissions in a battery-constrained environment

Assessing the real-world energy performance and emissions of plug-in hybrid electric vehicles (PHEVs) is complex: it depends on their usage (trip distance, recharging behaviour), which results in different combined uses of their thermal and electric propulsion. This article summarises the results of a Concawe study in which vehicle simulators were calibrated using experimental data (in-lab and onroad), allowing a comprehensive range of uses to be evaluated, spanning vehicle configurations, battery capacity, outside temperature and driving profiles. The results were synthesised through a method that weights each simulated use case according to its probability, based on statistics of daily distance travelled and temperature. The assessment was made for a wide range of battery capacities and recharging frequencies, and provided the real-world share of electric drive, CO2 emissions, and fuel and electricity consumptions of PHEVs according to these two key parameters. It concluded that, in an environment where the supply of batteries will very likely be constrained, PHEVs should be fostered to minimise greenhouse gas emissions providing that they are recharged at least every five driving days.