surfingslovak wrote:DaveinOlyWA wrote:interesting chart but i see a glaring issue with Minneapolis being warmer than Seattle. they are significantly colder making them significantly hotter in Summer and i think an analysis of sustained average temperature ranges is going to provide more accurate results.
Thanks for your comment, Dave. If you've read lukati's post above, you would see that this is exactly how it was done. There is not a lot of publicly available data out there, and we ended up sourcing temperature profiles from the same website. See further below to get an idea of how the profiles for Minneapolis and Seattle look like.
While we certainly can debate the validity of this data, I'm confident about the value I calculated for Minneapolis. It's within a degree or two of an empirically measured effective isothermal temperature published in a recent NREL study. It's so close that it can't be a coincidence.
As I said earlier, while I enjoy reading all comments on this board, I don't always agree with them. Especially if they are not based on hard data and models we can all compare against field data. Aside from Minneapolis and Seattle, this model predicts that both Hawaii and Florida are pretty hard on batteries. It should be interesting to see if and when we will get the first reports of lost capacity from there.
I don't mean to criticize, since you have a lot of EV experience, but I believe that we need to move away from a gut-feel approach to something more material and comprehensible to new EV owners. Tony demonstrated how it's done with his range chart. It's easily understood and very valuable. I wish Nissan came up with that, instead of their weasel response that "there is an infinite number of range scenarios".
Although there definitely is a nearly infinite number of temperature profiles and microclimates, I believe that it's important to come up with an easily understood chart that will give new owners an idea of the severity of the climate they live in. It would be good to have an assessment how well EV batteries will do in your climate before making a purchase.
Seattle Temperature Profile
Minneapolis Temperature Profile
you are right, i did miss the post and the charts you have provided are exactly what is needed