This phenomenon can be attributed to various factors related to the charging process at the wallbox. According to a study by ADAC, between 5 and 10% of energy can be lost during the charging process. This results in higher electricity consumption than the amount of energy actually charged into the vehicle.
The increased electricity consumption is due to charging losses and losses caused by various systems within the electric vehicle. Charging losses occur through the conversion of alternating current (AC) to direct current (DC), as well as through the inefficient conversion of electrical energy into chemical energy stored in the batteries. However, even in standby mode, electric vehicles can consume energy to maintain systems such as battery heating or cooling. These losses can increase electricity consumption even when the vehicle is not actively being charged. As a result, your electric vehicle may consume more electricity than was actually delivered by the wallbox.