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That's awesome! Do you charge at the office? Are you going to try to repeat the feat on the way home?

46 miles is 43% better than the notional EPA range of 32. By anybody's math that's a significant difference and one that Fisker should highlight. The fact that you did this in real-world conditions and at real-world speeds is even more impressive.

So details: Did you use hill mode? Any hypermiler tricks like drafting or babying the throttle?

Brent
 

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LonePalmBJ said:
That's awesome! Do you charge at the office? Are you going to try to repeat the feat on the way home?

46 miles is 43% better than the notional EPA range of 32. By anybody's math that's a significant difference and one that Fisker should highlight. The fact that you did this in real-world conditions and at real-world speeds is even more impressive.

So details: Did you use hill mode? Any hypermiler tricks like drafting or babying the throttle?

Brent
Thanks. I was actually pretty impressed myself. I have Level II charging available at the office and will try to repeat the feat on the way home, but since the trip back is generally uphill, especially the part close to my home, I expect to have to rely on the ICE for a few miles toward the end.

I only engaged Hill mode when I was coming down the fairly steep hill during my first 5 miles, or when I was in heavy traffic in order to save on friction braking. The rest of the time, I had Hill mode off and concentrated on keeping the Generate/Accelerate needle as close to neutral as possible. I also kept the speed at or below 65 MPH. Even without hill mode, you can recapture a fair amount of energy by taking your foot off the thrust pedal and coasting down hills. It was difficult to do any drafting since pretty much everyone was going much faster than me. I could probably draft behind trucks, which tend to move a bit slower than the cars, but there are not a whole lot of those on 280.

This was pretty interesting as an exercise, but I don't think I can do this every day since I actually enjoy driving my Karma too much to neuter it in order to get more range, and it also takes a lot of concentration and discipline to drive the car in max economy mode. I suspect, I will go back to burning (small amounts of) gas in exchange for better performance once this flirtation with hypermiling ends.
 

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Discussion Starter · #23 ·
Following up on my original post, this week I completed the round-trip commute of 24 miles and had 26 miles left of battery range, meaning for the first time ever my entire round-trip commute (so elevation changes are factored out) was driven with 1:1 battery:real miles. The keys are: minimize A/C use (none during my round trip since the weather was in the 70s), and minimize braking and accelerating within reason. I did not draft intentionally, and several miles of 65-75 mph highway travel is part of each leg of the commute.

The definitive data that completes the story is that my charge after that commute required only 9.479 kWh, consistent with having 26 miles left of battery charge. Last Thursday I charged the battery from empty and it accepted 19.79 KWh, so all the numbers work out (19.79 KWh = 50 Miles predicts that 24 miles of used range should consume 9.499 kWh, and in reality I consumed 9.479 KWh).

So if you drive skillfully and don't need the A/C, you CAN get ~50 miles of range over a very typical round-trip, part highway, commute.
 

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drliu said:
... So if you drive skillfully and don't need the A/C, you CAN get ~50 miles of range over a very typical round-trip, part highway, commute.
Cool (literally, in the case of "don't need the A/C" :D).

Unfortunately here in Utah one needs A/C from about late April until (mid) September, and heat from (mid) October until March. Fortunately my commute is much shorter (normally, "down the hall", but until the house is done there's a daily trip to the house) and my errands tend not to be very far either. I just also have those not-infrequent other trips that involve going 100+ miles in a day, where I need the range extender.
 

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It's too bad that Fisker did not incorporate Ford's technique of shutting down the ICE on their hybrids. It is programmed to stop the ICE so that the pistons are in optimal position for restarting the ICE. The net result is that the engine shutting off and restarting is almost imperceptible.

Two things that Ford did very well on their hybrids that I wish Fisker could incorporate: Engine start/stop and the Sync/Nav/Entertainment interface. Their interface is slick, much more polished than the Karma. (Almost all of the same functionality, also).

Ed


Deep Ocean said:
Excellent write up on the stealth vs. sport modes Brent. Most owners stay in stealth all the way to zero then accept the fact that they'll be on the ICE for the remainder of the trip. Another thing I always found amusing is the "shake" when in Stealth with zero miles on the battery, ICE running, sitting at a stop light and the ICE shuts down and shakes the car. If you don't know what's happening you think someone bumped your car. It reminds you of the uniqueness of this wonderful machine!
 

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I heard the new batteries have some improved firmware that allow it to calculate SOC better and also allow more of the battery to be used. Has anyone else heard this?
 

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RE: Personal Best: 46 Miles on a full charge at (mostly) highway speeds

Fabulist said:
As an exercise in range extension, I managed to drive all the way to work today in EV mode, a distance of 46.0 miles according to G-Maps:



The first 5.5 miles and the last 1/2 Mile of the trip are on city streets and the remaining 40 miles are on highway I-280, which tends to be very fast moving. On the highway portion, I kept my speed below 65 MPH, which meant that I was getting passed by fat guys on scooters and every other motorized conveyance (a few of which flashed me thumbs-up anyway before speeding off), but it was pretty impressive to pull into the garage at work without having to turn on the ICE.

Today was a pretty cool, but not cold day, and the drive from San Francisco to Cupertino tends to be generally downhill, but with a couple of large hills along the way. Here's the actual elevation profile:



Given all of this, and the fact that I drove most of the way at 60-65 MPH, I think it is remarkable how close to the 50 Mile range I managed to get on a single charge.

Update 1: On the return trip, I started with a fully charged battery and to the extent possible, I used the cruise control to keep the speed at 65 MPH. As expected, the battery did not last as long on the return journey during to the rise in elevation, and possibly also due to the lower evening temperatures, and at 42 Miles the ICE kicked in to get me home. Overall, I got 88 miles out of two full charges or 44 Miles average/Charge, which is pretty respectable given the conditions.
Update 2: There was not much doubt that speed matters when it comes to range, but I nevertheless confirmed it today when I abandoned my hypermiling ways and actually kept up with traffic today as I drove to work. Without getting too specific, let's just say that the traffic on I-280 moves pretty briskly, which is why it is a favorite speeder hunting ground for the California Highway's finest. I tried to stay with the pack but did not drive aggressively. At higher speeds and under almost exactly the same ambient and loading conditions as yesterday, the battery was depleted 7.5 miles short of the destination, giving me a total EV range of 38.5 miles. So I had to give up a bit of MPG to not get passed by this guy:



But I think it was worth it. :D
 
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