Europe’s heatwave exposes where EVs are most vulnerable

The most important difference is no longer simply whether a car is electric or powered by a combustion engine. What matters is how well it can manage heat in the battery, cabin, charging electronics and the charger environment itself. This is where advertised peak power and real-world performance start to part company.

In the current European heat, the recurring pattern is clear: range falls, fast charging can take longer and the reliability of the chargers themselves matters more than it does on an ordinary day. That does not mean electric cars are unsuited to hot climates. It does mean that at 35–40 degrees Celsius, a car’s real capability becomes much more obvious than it is on a 20-degree test day.

Owners’ experience: the problem is not driving, but charging

The EV itself usually copes with heat reasonably well. The most common owner complaint is not that the car will not move, but that it does not charge as quickly as expected, or that the advertised range disappears faster than usual.

When a combustion-engined car starts to suffer badly in hot weather, the conversation turns to overheating, coolant, fans and roadside breakdowns. With an electric car, the picture is more subtle: the car protects itself. If the battery, charging cable or charging-station electronics get too hot, power is reduced. The owner experiences that as slow charging, not as a fault.

In practice, that can mean a fast-charging stop that would normally take 18–25 minutes stretches beyond half an hour, or longer. The car may be technically fine, and so may the charger, but the operating conditions are simply against it: hot asphalt, direct sunlight, a high battery temperature after motorway driving and a charging station whose cooling system is already working near its limit.

The worst-case scenario is a long, fast drive, arriving at a charger with a low state of charge, high outside temperatures and a desire to charge immediately to 80 or 90 percent. The battery is already warm from driving, fast charging adds more heat, and the thermal management system has to choose between two things: giving the driver a headline charging number on the screen or protecting battery life. A well-engineered car chooses the latter.

Some models handle heat better than others

It has to be said, however, that the current European heatwave has not yet produced a reliable model-by-model ranking showing that one particular model has failed and another has clearly come out on top. Conclusions like that require far more data than a handful of owner posts.

There is, however, earlier large-scale and practical data showing which cars tend to retain range better in hot weather. Recurrent’s dataset of nearly 30,000 EVs showed that at around 32 degrees Celsius, the best performers included the Audi Q8 e-tron, BMW i4 and Rivian R1S, all of which retained about 98 percent of their ideal range. The Hyundai Ioniq 5 and Rivian R1T were close behind, at around 97 percent. The Ford Mustang Mach-E and Chevrolet Bolt EV were around 96 percent, while the Tesla Model 3 and Volkswagen ID.4 were around 95 percent.

That does not mean Audi, BMW or Rivian are automatically better than everything else in all hot conditions. It means the thermal management and energy use of those specific models worked well in summer heat within that dataset.

Once temperatures climb towards 37–38 degrees Celsius, the gaps grow larger. According to the same dataset, the BMW i4 and Rivian R1S retained around 92 percent of their range, while the Hyundai Ioniq 5 retained around 90 percent. In some models, the loss can exceed 20 percent. For an owner, that is a noticeable difference, especially on a motorway run or with a car loaded for a holiday.

Tesla does not cope badly with heat, but the promised number can mislead

Hot weather always creates plenty of debate around Tesla, partly because there are so many cars on the road and the owner community is vocal. Technically, Tesla’s heat tolerance is not poor. Its cars use active thermal management, battery preconditioning and tightly integrated software. The issue is more that Tesla’s official range figures are often ambitious, and the gap becomes especially obvious in hot motorway driving in the real world.

A good example is What Car?’s hot-weather test in Spain, where the Citroën e-C3, Kia EV3 and Tesla Model 3 were driven in temperatures between 32 and 44 degrees Celsius. The Tesla Model 3 covered the greatest distance and was strong on efficiency, but it also fell the furthest short of its official range in percentage terms. That does not mean Tesla is weak in the heat. It means the official claim and a genuinely hot motorway are two different things.

The Kia EV3 also performed well in that test, covering practically the same distance as the Tesla despite having a lower official range. The Citroën e-C3 covered less distance in absolute terms, but its battery and price sit in a different class. A test like this should not be judged only as a percentage of the official WLTP figure. The actual distance covered, energy consumption and the price segment of the car all matter.

Hyundai, Kia and 800-volt cars have an advantage when charging

On a long journey in hot weather, battery size alone is not enough. What also matters is how quickly the car can put energy back into the battery without overheating it. This is where Hyundai and Kia’s 800-volt architecture remains a strong argument. The Ioniq 5, Ioniq 6, EV6 and newer larger models are not good only because of peak power. They are strong because, in favourable conditions, they can keep the charging curve relatively high.

In ADAC’s 2026 measurements, the Mercedes-Benz CLA EQ, Porsche Taycan, Mercedes EQS, Hyundai Ioniq 6, Audi A6 e-tron and Audi Q6 e-tron all look particularly strong. This is not a direct heatwave ranking, because ADAC tests under controlled conditions, but it does show which cars combine a large battery, low consumption and consistent charging performance. In hot weather, that combination matters.

The Porsche Taycan and Hyundai/Kia’s 800-volt models are well placed because they can accept a lot of energy quickly during fast charging. The Mercedes EQS and new CLA EQ play a different game: very strong efficiency and long real-world range reduce the need to stop at chargers so often. During a heatwave, the best charging stop is the one you do not have to make at all.

Older cars and simpler cooling systems are in a weaker position

If there is a heat-related risk group, it is not “all electric cars”. It is older cars with smaller batteries, models with simpler battery cooling and cars whose fast-charging capability is modest to begin with.

The Nissan Leaf is historically the best-known example here, because earlier generations lacked active liquid cooling. That means hot climates and repeated fast charging are not its strongest use case. The same logic applies to other older or cheaper electric cars with simpler battery thermal management and more limited charging power.

A heatwave also exposes the importance of battery size. A small-battery car can still make perfect sense in the city, but if a summer holiday route involves 40-degree heat, motorways, family, luggage and public chargers, every percentage point starts to matter. A small battery simply leaves less room for error.

The chargers themselves can be the weak link

The practical heatwave story does not end with the car. The charging station itself can also reduce power because of heat. That applies both to public fast chargers and home wallboxes.

With home charging, the issue can be very simple: a garage can turn into an oven. If the charger, cable or adapter is working at high current in a hot, enclosed space, everything gets hotter still. In that situation, the charger may reduce current or stop charging altogether. The owner experiences it as a fault, but in reality the system is protecting itself from overheating.

At a public fast charger, the situation is similar, only on a larger scale. High power means a lot of heat. If the charger is standing in direct sun on hot asphalt, and several cars in a row are drawing high power from it, thermal throttling becomes entirely realistic. That is why, during a heatwave, it makes little sense to judge a car only by whether 230 kW briefly appeared on the screen. What matters is how long the car can sustain high power.

What the current heatwave actually proves

The current European heatwave proves that there are major differences between electric cars in thermal management and charging strategy, and that those differences become visible in extreme weather.

The cars best placed to cope are those with long real-world range, effective cabin cooling, an actively liquid-cooled battery, good battery preconditioning and a stable fast-charging curve. Based on today’s data, that includes the better-performing models from Mercedes, Porsche, Audi, BMW, Hyundai/Kia and Tesla — but not automatically every car from any one manufacturer.

Owners of models with smaller batteries, weaker charging capability or simpler thermal management need to plan more carefully. That does not mean those cars are bad. It means a heatwave leaves them with less margin.

Ultimately, the current heatwave shows how good a car’s real energy use is, how much of its official range remains and how intelligently it protects its battery. From an owner’s point of view, the best electric car is not the one with the highest advertised peak power. It is the one that can get through a hot day calmly, predictably and without drama.