Electric cars and winter: why autonomy drops and by how much

The decrease in autonomy of electric cars in winter it is a real phenomenon, concrete but often not as catastrophic as it is sometimes portrayed. The number of kilometers that can be driven after a “fill up” of electrons is lower than in milder seasons due to physical reasons and issues related to the use of the car during bad weather. Adac data – the German counterpart of Aci – highlight that on a 100 km journey at typically winter temperatures (0 °C) a not too efficient electric one can consume 30% more energy compared to the same route with a more lenient climate (20 °C). What causes the phenomenon, and what can be done to mitigate it?

DECREASE OF AUTONOMY IN WINTER

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The ADAC and the American Department of Energy underline how the reduction in autonomy of electric cars in winter depends largely on the heating of the passenger compartment and occupants. The efficiency of the system available in the car therefore plays a crucial role for those who travel a lot and often in very cold areas. Modern electric cars almost all allow you to have (as standard or for a fee) the heat pumpthe preferred system to minimize the reduction in autonomy in winter. Those that don’t have one and use a traditional one to heat the air resistence instead they are more sensitive to the cold, in other words they consume more energy. Heating is not the only cause of lower mileage for electric cars in winter: batteries and their chemistry also suffer from the coldbecause at low temperatures the electrochemical exchanges inside the battery slow down and the internal resistance increases. However, the drop is “reversible”: in conditions of normal use, the cold does not damage the batteries. Electric cars with thermal tires also “pay” for the greater rolling resistance and the higher density of the cold air which determines greater aerodynamic resistance. However evolution of battery chemistry and the adoption of pre-heating systems and heat pumps are gradually mitigating the phenomenon.

HOW TO REDUCE THE DROP

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There are measures to contain the decline in the autonomy of electric cars in winter. First of all, it is possible precondition the car while it is chargingusing the energy of the house or the charging station rather than that of the battery. Many cars also allow you to set a departure time so that the management system brings the battery to the ideal temperature. Driving, however, especially if you are traveling alone, can be useful heat the steering wheel and seats rather than the entire passenger compartmentor set the heating to a comfortable but slightly lower temperature. Also, if you need to quickly recharge the battery while traveling, it’s better set the stop on the navigator: if the car can preheat the battery it will do so, so for the same amount of time spent at the charging station the recharged energy will be greater. For the rest, the precautions that are always valid are good: driving as smoothly as possible, use of regenerative braking, tires at the correct inflation pressure.