Happy to see objective data here to prove that it is merely a 'myth' that EVs are affected more than ICE.
I call BS. Not my experience at all.
As someone already mentioned, you just have to check fuelly.com to see the reports during winter months. Follow any of the fuel economy or hypermiling forums, and they will echo the sentiment that winter is the worst time for fuel economy, regardless of platform.
I have been running diesels for the last few years, maybe they are affected more than 'gas'. I've tracked the fuel consumption continually and there's really been no objective impact by cold weather.
If you are driving a diesel, then it is more than likely forced induction (not necessarily, but likely). So you will likely see a small improvement in engine efficiency due to denser air. However, you will also see additional pumping and heating requirements because diesel starts to get really thick in cold weather.
But we have a MPV 'gasser' at the moment now, with the Ampera, and it delivers 25mpg in summer. If I started seeing 15mpg in winter I'd have a fit and send it off for scrap! But going from 50 miles in the Ampera to 30 miles seems par for the course.
Again, smaller battery so a larger percentage of its charge goes to heating the cabin. Assuming half of the decreased efficiency is from heating, that would mean you're losing about 2 kWh to running the heater. That's 20% of the Ampera's available energy, but would only be 3% of the Bolt's available energy.
Also, continuing that line of thought, it would equal a roughly 20% drop in fuel economy for your MPV in the same conditions. Would you send your MPV off to get scrapped if it only got 20 mpg in winter? I hope not, because that is more than likely what you'd experience in those winter conditions.
Sorry. No way. EVs are definitely more heavily impacted by cold weather than ICE. Absolutely no question about it, and you're BS-ing yourselves if you think otherwise.
Define "more heavily." The only advantage ICEVs have is scavenged heat. In a Bolt, that's an additional 3% loss, which I wouldn't consider "more heavily impacted." Especially because you also have the option of preconditioning.