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Range Delirium

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Joined: 1 month ago
Posts: 15
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I know this is probably touching the third rail with this group, but I am honestly curious.  So, we have EPA, WLTP (and apparently CLTC and NEDC mileage ratings).  Within each of these ratings systems there are assumptions and "factors" that can be applied in accordance with each manufacturer's marketing strategy.

Here is my question - how does the car know?  It is exciting to see HF's HMI indicate he has over 350 miles to go after it was fully charged, but how does it know?  In fact, why does it not say you have over 400 miles to go as predicted by the WLTP testing?  I assume there is some sort of adaptive software that will adjust mileage assumptions per your driving history, but out of the box I would think it would be more optimistic and match the WLTP estimate?  Did marketing not get hold of the on-board predictive software?


I am not casting aspersions and it sure seems like the One/Extreme will have outstanding range and will soon have its needed EPA certs.  It's just that this Christmas when I am out in my Extreme cutting down my our Xmas tree in the Blue Ridge Mountains I would like to be able to make it to the next pub and rely Hal, my on-board AI friend, to get me there.


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Joined: 11 months ago
Posts: 1067

These are commonly referred to as GOMs which is an acronym for Guess-o-meter. That should tell you most of what you want to know! Different OEMs take different approaches to this (and different approaches in different geographies). Tesla runs EPA as a baseline on its US cars for the headline number but runs a much more sophisticated estimate on the trip screen that includes driving style, traffic, weather, etc. based on your destination. Some run very conservative numbers some run adaptive algorithms, some run what feels like guesses (cf the original Nissan Leaf which gave birth to the acronym). 

In short, no one knows how Fisker will implement this or how it will evolve over time. 

Joined: 11 months ago
Posts: 126

I think that in the USA, your going to get close to the epa range as its more realistic. Possibly exceed a little.

In Europe your going to be mighty disappointed as you won't get anywhere near the claimed 440 miles. 


Ordered Fisker One. Mariana Blue. F3a Slipstream sea salt interior

Joined: 11 months ago
Posts: 97

In the US, you get EPA range if you drive at 55mph. The speed limit on highways and freeways is 65mph to 70mph in mostly and in few states it is 80mph. If we drive at 70mph just 5mph over 70mph, the range will be 20% less than EPA range. So, if EPA is 350, I would expect about 290 miles in realistic driving conditions if you drive at the speed of the middle lane in a 3 lane highway. However, if we charge 100% before a long distance trip, it is good practice to charge at 20%. 80% of 290 miles is about 240 miles. At that point charging to 80% could take 30 minutes. That allows driving another 190 miles. We average about 62mph in the US if we drive at 70mph due to traffic. So, it is possible to drive for 4 hrs, stop for 30 min and drive for 3hrs and arrive at 20%. Total 430 miles and charge over night and do it again the next day. This is what I expect.