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Old 08-14-2009, 11:44 PM   #2 (permalink)
Engineering first
bwilson4web's Avatar
Join Date: Mar 2009
Location: Huntsville, AL
Posts: 792

14 i3-REx - '14 BMW i3-REx
Last 3: 45.67 mpg (US)

17 Prime Plus - '17 Toyota Prius Prime Plus
90 day: 58.25 mpg (US)
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Thanked 196 Times in 126 Posts
I was able to go back and this time record mileage. At 2:00 AM, I was able to run a 50% power run too:

power miles MPG mph
100% 1.5 23.8 35
_75% 1.5 25.3 26
_50% 1.5 22.2 16

On the descents, I simply put the car in "B" and let gravity and the spinning engine do the rest. But I noticed the battery fully charged and the top bar, slightly pink, was illuminated.

I returned to my starting point, about a mile away from the base of the hill and the battery was still fully charged. On the second run, the battery charge still showed full as I approached the base of the hill. I suspect this is why the middle run showed exceptionally high mileage, a battery boost.

For the last run, I used "EV" mode to bring the battery out of the 'pink bar,' full charge and then used regular "D" to approach the hill. Until there is a standard way to normalize the battery charge, I won't be able to trust this data.

To handle the battery energy contribution, we need to measure the traction battery current. Then comes the challenge of trying to use the charge/discharge energy flow to compensate for the altitude and distance.

Bob Wilson
2019 Std. Range Plus Model 3 - 134 MPG3 || 2014 BMW i3-REx - 117 MPGe, 39 MPG
JuiceBox 40 Pro (240 VAC, 40 A), KHONS portable (120-240 VAC, 12-32 A)
Retired engineer, Huntsville, AL (five times AutoPilot saved.)

Last edited by bwilson4web; 08-14-2009 at 11:54 PM..
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