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For other data geeks like me, I wanted to share what I've learned about temperature and range in the Fisker Karma.

We know we lose range when it gets cold, but I wanted to know by how much. I also wanted to know if we lose range as it gets really hot. I am sure a Fisker Engineer worked this out in a simulator, but I wanted to get real-world measures. I logged my travel to a fixed point from my house, and back... I wanted to see where the sweet spot of maximum range, and what happens when it gets hot, cold, etc. Since I live in the mountains, to airport is a drop of about 2000 feet, and home is back up the hill. Merging the too gives a good estimate of the % range gained/lost in relationship to temperature. The range of temperature is from 20 degrees to 98 degrees. (-7 to 38 Celsius).

My data is below. The sweet spot of maximum range is 75 to 85 degrees (24 to 29 Celsius).

The variability is how fast I was driving -- sometimes I am running late to the airport, and I've shared previously the relationship between e-range and speed. As one exceeds 65mph, range drops a lot. There is also a little bit of noise in my temperature measurement range from where I live and where I was traveling to (I used one number roughly in the middle of the range). That said, for a basic model that leaves out my speed, temperature alone explains a lot of the variation in electric range. It would be cool if the Karma computer sensed the temperature and used it in the algorithm for estimating the range (rather than using the fixed 50miles so we had a realistic projection).

I posted the data chart on the newfisker site.

Two other things I am interested in... 1) what is the magic number at which our range flips from 409 to 0... since it picks up again and starts counting. (I think it is 455.5miles - but plan to refuel and start the counter and double-check.)

The other thing I am interested in is whether we lose range as the battery is used. But that is a slow process as I am only at 23k miles. So if someone else has been logging their miles to and from a fixed point, and noting the temperature, they might get to an answer faster than I do. If so, keep us posted.

If anyone else is a data geek, and already unlocked these mysteries, share what you've learned please. I'm always curious about what we can learn from measurement. (It's an occupational hazard).
 

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This is indeed excellent. To add to the data above, I too did a few measurements. I can take two routes to my work, one via a highway and one via a fairly busy road at slower speeds. I have noticed that I lose between a third to sometimes half the range if I am traveling on the highway at speed compared to the slow moving road. I have also noticed that really hot temperatures above 30 Deg C reduce the range in agreement with the above post. I don't know how the Teslas act and whether they lose range also but I must assume all electric cars go through the same issues with range.
 

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I see the same behavior - best range between 75-85 degrees Fahrenheit. Reduced range in extreme heat (we get that a lot here in Phoenix). My Volt exhibits the exact same behavior, and I see about a 20% reduction in electric range in the Volt between the Summer and Spring/Fall when temps are very moderate. It rarely gets cold here so I won't even pretend to say that affects our range in Phoenix.
 

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We are not that fortunate in Toronto, Canada. Extreme cold and extreme heat are what we get sometimes and it sucks not just for the car but for everyone!
 
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