At the end of September 2020, a study by the Fraunhofer Institute for Systems and Innovation Research
ISI, together with the non-profit research organization International Council on Clean Transportation (ICCT), caused a stir. The authors had examined the everyday use of 100,000 plug-in hybrid vehicles in Europe, North America and China. The results were not very flattering: "On average, the real-world fuel consumption and CO2 emission values of plug-in hybrid vehicles for private drivers in Germany are more than twice as high as indicated by the official test procedure. For company cars, the deviation is even four times the official values," summarizes Coordinator of the Business Unit Energy Economy at Fraunhofer ISI and lead author of the study.
This means that the deviation between official data and real empirical values for plug-in hybrid vehicles is much greater than for vehicles with conventional combustion engines. The researchers found that plug-in hybrid vehicles are charged too rarely. This reduces the electric reach and increases the fuel consumption and the CO2 emissions in everyday operation.
An unnecessarily high fuel consumption, and the associated excessive CO2 emissions, are therefore not due to technical reasons, but to human factors. The developers at ZF were aware of this problem and developed two digital assistants to help counteract it. Installed in their EVplus concept car, ZF presented the "ZF eDriver Trainer" and the "ZF Zero Emission Zone Manager" to the public in mid-September.