alt Hacker News> Most notably, air is about 28% denser at -40°C than at 25°C, so drag is about 28% higher. So you would expect roughly 28% less range at high speeds even if the battery has no capacity loss whatsoever.
With my gas car, I haven't noticed 30% worse fuel consumption at –30°C compared to +30°C [0]. To be fair, I haven't closely measured the fuel consumption at different temperatures, but I probably would have noticed such a big difference. This is just anecdotal of course, so your values may actually be correct.
[0]: It does occasionally get down to –40°C here, but my car won't usually start then, so I've slightly shifted your temperature range to the values where I've driven most.
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It won't be as noticeable on a gas car because it is probably starting out around 30% efficiency (as compared with ~90% for an EV). This is a major advantage of gasoline, in a sense, because it means we have already engineered the package to account for a lot of wasted fuel.
Air drag energy losses are tiny comparing to other losses when burning petrol so you don't notice the difference.
Gas cars produce more power at lower temperatures - more oxygen gets into the combustion chamber, and the engine also can run more advanced spark timing without as much worry of detonation. This is why turbochargers have intercoolers.
I drive long distance weekly on my gas car. Full tank in summer (+20C) gives me 520 km, while in winter (-20C here) I get 430-440 km. I noticed it on my current and previous cars. Maybe it's thicker oil and worse car efficiencies in winter ? And that's despite that full tank of gas has more gas in winter comparing to summer, gasoline is denser in cold temps.