Extreme temperatures don’t just make drivers uncomfortable, they can also hit electric vehicles and hybrids where it hurts most: efficiency, driving range, and operating costs. A new study from AAA shows that both scorching heat and bitter cold can have a measurable effect on how electrified vehicles perform in the real world, with cold weather creating the biggest penalties overall.
AAA tested six vehicles, including three EVs and three hybrids, in controlled conditions at 20 degrees, 75 degrees, and 95 degrees to see how weather changes affected efficiency and operating expenses. Researchers used a chassis dynamometer, essentially a treadmill for cars, while keeping climate control systems set at 72 degrees inside the vehicles.
The findings were eye-opening, especially for drivers who live in areas where temperatures swing dramatically between seasons.
At 95 degrees, hybrid vehicles experienced a 12% drop in fuel economy compared with moderate 75-degree conditions. EVs saw a 10.4% reduction in efficiency and an 8.5% decrease in driving range. AAA says much of that loss comes from the additional energy required to cool both the cabin and the battery pack.
Cold weather was even tougher on both types of vehicles.
At 20 degrees, hybrids lost 22.8% of their fuel economy. EVs took the largest hit, suffering a 35.6% drop in efficiency and a 39% reduction in calculated driving range. In other words, an EV rated for 300 miles of range under ideal conditions could effectively lose more than 100 miles of usable range in severe cold.
AAA’s Greg Brannon, director of automotive engineering and research, said the organization expected EV range losses in cold temperatures based on earlier studies, but researchers were surprised by how much hybrid fuel economy dropped in winter testing.
The study also looked at how weather affects operating costs, and the results varied significantly depending on whether EV owners charged at home or relied on public chargers.
In cold weather, hybrid operating costs increased by $28.44 per 1,000 miles driven. EVs charged at home saw operating costs rise by $32.11 per 1,000 miles, while EVs using public charging stations jumped by nearly $77 per 1,000 miles.
Hot weather was less punishing financially, but it still mattered. Hybrid operating costs rose by $13.02 per 1,000 miles in high heat. EVs charged at home increased by $6.78 per 1,000 miles, while public charging added $16.25 per 1,000 miles.
One of the more interesting findings involved the cost comparison between hybrids and EVs. In cold weather, EVs remained cheaper to operate than hybrids if charged at residential electricity rates, saving about $36 per 1,000 miles. But if owners depended primarily on public chargers, EVs actually became more expensive to operate than hybrids by roughly $86 per 1,000 miles.
The same pattern showed up in hot weather. EVs charged at home were cheaper to run than hybrids by about $46 per 1,000 miles, but EVs relying on public charging cost roughly $41 more than hybrids.
AAA says the study highlights something consumers should think carefully about before buying any electrified vehicle: where they live and how they charge matter almost as much as the vehicle itself.
For drivers in mild climates with access to reliable home charging, EVs can still offer lower operating costs overall. But in regions with harsh winters, long driving distances, or limited home charging access, hybrids may remain the more practical choice for many buyers.
The research also reinforces something longtime EV owners already know: advertised range numbers are best viewed as ideal-condition estimates, not guarantees. Temperature, terrain, speed, climate control use, and charging availability all play a role in what drivers actually experience day to day.
In other words, Mother Nature still has a bigger say in vehicle efficiency than most window stickers would lead you to believe.