LoginEVs Might Hate The Cold, But Hybrids Hate The Heat
- AAA tested electric vehicles and hybrids in controlled climate conditions.
- Cold weather had a much larger impact on EV driving range than heat.
- Hybrids also lost efficiency in extreme temperatures during testing.
Got your hands on a shiny new EV or hybrid, and wondering why its range isn’t quite as much as quoted? Well, some of that discrepancy can be down to the controlled nature of official range tests, plus a healthy bit of marketing fluff.
But there’s another reason as to why that 300-mile EV or 800-mile plug-in hybrid isn’t quite making those headline numbers. It simply doesn’t like to run when it’s too hot or too cold outside. So what are the specifics, then? You can thank AAA for expanding and updating this line of research, which they began in 2019.
A Climate-Controlled Treadmill Test For Cars
How they did this kind of testing is no less cool. They took three hybrids and three EVs and placed them in a laboratory test cell that included a dyno. In other words, it was the equivalent of running on a treadmill in a temperature-controlled room. Then, they set the vehicle’s air conditioning and heating systems to a comfortable 72F. Meanwhile, the test cell’s temperature was varied. Engineers at AAA settled on three temperature values – namely 20F / -6.7C (a cold winter), 75F / 23.9C (your average day), and 95F / 35C (a hot summer’s day). And they drove.
Read: EV Range Claims Still Sound Great, Until Freezing Temps Hit
Taking 75F / 23.9C as the baseline, AAA found that at 95F / 35C, the electric vehicles lost an average of 8.5% in driving range, corresponding to a 10.4% efficiency reduction. Hybrids fared worse, with a 12% decrease in fuel efficiency (miles per gallon). These values are noticeable, but unlikely to create a noticeable impact unless you tend to push the range envelope before recharging or refueling. This also means that your wallet will take a mild hit in terms of cost per mile.
Cold weather tests were rather more concerning. At 20F, the EVs saw a whopping 35.6% efficiency drop, resulting in an average range reduction of 39%. Hybrids also took a noticeable hit, with a 22.8% drop in fuel efficiency.
The Bottom Line
If you live in a part of the world where winters and summers are mild, and the temperature generally hovers around 75F or thereabouts, congratulations, you don’t need to worry too much. If you live in a place where summers are hot, you’ll need to account for some extra range when purchasing your EV if you plan (or if your commute dictates) to run it down to 20% before every charge.
But if you live in a place where the winters are harsh, you may want to evaluate your options. As Greg Brannon, Director of Automotive Engineering and Research at AAA, said, “EVs are efficient in moderate temperatures but lose significant range in the cold. We expected this from our previous research, but were surprised by the 23% reduction in fuel economy for the hybrids in cold temperatures. Drivers should consider climate, energy costs, and driving patterns when choosing a vehicle that best fits their lifestyle.”
