With air conditioning ...

E-car in a hot summer traffic jam – will the battery last?

(Bild: ADAC/Uwe Rattay)

On hot days in traffic jams, the air conditioning systems in electric cars draw a lot of power from the battery. The ADAC has now investigated whether this increases the risk of stopping with an empty battery.

Electric cars are significantly more efficient in traffic jams in the summer heat and therefore more environmentally friendly than cars with combustion engines. The ADAC has now established this in a simulation in a new climate chamber at the Landsberg Technology Center. The climate chamber complements the test infrastructure specifically for electric cars, which already includes a chassis dynamometer and fast-charging technology.

In an initial laboratory test, a Tesla Model Y was exposed to the conditions of a typical summer day with a maximum temperature of 35 degrees and intense sunlight from UV lamps for eight hours in the climate chamber, which enables simulations in the temperature window of -20 to +40 degrees.

(Bild: ADAC/Uwe Rattay)

 At the same time, the air conditioning in the vehicle was set to 20 degrees and the camping mode was also selected, which enables continuous air conditioning. Exposure to the UV lamps heated the windshield to up to 60 degrees and the dashboard to up to 45 degrees, while the measured interior temperature always remained below 25 degrees.

During the eight hours, the Tesla SUV consumed 12 kWh, which corresponds to a loss of 1.5 kWh or 8 km range per hour. According to the ADAC, a car with an internal combustion engine would consume 1.0 to 1.5 liters of fuel per hour under the same conditions. Converted, this amount corresponds to an energy content of around 10 to 15 kWh. An electric car is therefore much more efficient and therefore more environmentally friendly, especially as it does not produce any exhaust fumes locally. The fear of getting stuck in a traffic jam on a hot day with an electric car is unfounded in view of these results. Nevertheless, the club recommends ensuring that the battery has sufficient remaining capacity, even in summer.