Don
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Location: Biloxi MS

Re: Measured Wall-to-Wheels Consumption

Tue Oct 02, 2012 2:31 pm

I have driven exclusively in the B mode since we bought the car May 9th - Almost 4500 miles now. Like you, I'm so used to 'feathering' the throttle on delcleration now that I almost never touch the brakes until I'm down to the 10 or 15 mph range

It just makes more sense to me that using all the regenerative braking I can must be more efficient than using friction braking - I'm glad (but not surprised) to see that your measured consumption proves this

Don
2012 iMiEV SE Premium, White
2012 iMiEV SE, White
2017 Chevy Volt Premier
2014 Ford Transit Connect XLT SWB wagon, 14,000 miles
1979 Honda CBX six into six

JoeS
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Re: Measured Wall-to-Wheels Consumption

Mon Nov 26, 2012 7:36 pm

Have now covered over 9114 miles (14667km) since early February and here's the latest actual measured energy consumption (from the wall) summary since I started keeping track:

Distance driven with measurements: 8055.5mi (12964km)
Energy consumed: 1916.354kWh
Yielding:
Average 4.204miles/kWh (6.765km/kWh)
Average 0.238kWh/mi (0.1478kWh/km)
Average 23.8kWh/100mi
Average 14.8kWh/100km


All the caveats of my 6/15/12 posting apply.

Don't forget, this is wall-to-wheels which means that the actual energy delivered from the grid to the vehicle has been measured, and the onboard charger inefficiencies are included. This must not to be confused with, e.g., the Leaf's dashboard readout which DOES NOT include the charger.

I had also been keeping track of my Range Remaining each time I fully recharged, and the numbers range from a low of RR = 48mi (77km) to a high of RR = 98mi (158km), with an overall average of RR = 69.9mi (113km). To this day, I am unable to predict what that number will be when I fully charge up the car.

Although I do keep track of whether I was using L1 or L2 (to see what the % of each is), it doesn't mean anything as for all of our local driving L1 would certainly suffice. L2 is simply handy to top up the car quickly for added insurance, or when taking longer trips.

I've been keeping track on a daily basis, dutifully adding up the individual hourly energy consumption increments off my T.E.D. (The Energy Detective), using the Kill-A-Watt (120vac) and a separate kWh meter (240vac) to corroborate the readings. Whenever I charged at a public EVSE or a friend's house, I recorded the exact amounts consumed. Finally, each time I fully charged the car I added up all the preceding partial-charge readings and put them into this spreadsheet.

BTW, the Mitsubishi (Panasonic) L1 EVSE itself consumes 5W or 14VA (miserable power factor), so I've been turning it off when not in use.

The purpose of this exercise was to measure the actual wall-to-wheels motive energy consumption of the iMiEV. Earlier in the year when it was still cool I used the heater very sparingly and during the summer I also barely used the aircon, so the readings are fairly reflective of what the car uses. Now, since I have full confidence in the iMiEV's achievable range, I've recently taken to using its heater with wild abandon, as well as pre-heating the car at every opportunity. This wreaks havoc on my data-taking and I think I'll now throw in the towel on this exercise as my objective has been achieved.

I can categorically say that, on average, my iMiEV goes 4.2miles/kWh (6.77km/kWh). Put another way, my iMiEV has a superb efficiency of 0.238kWh/mi (0.148kWh/km) in roughly a 50/50 mix of city/highway travel. :geek:
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

PV1
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Re: Measured Wall-to-Wheels Consumption

Sun May 05, 2013 4:54 pm

JoeS wrote:Average 4.204miles/kWh (6.765km/kWh)
Average 0.238kWh/mi (0.1478kWh/km)
Average 23.8kWh/100mi
Average 14.8kWh/100km


Does tire pressure from stock to 55 psi have a big impact? I haven't measured my tire pressure yet, but I'm running on where they were at the dealer. I also use coasting and regen like they should be used, but I have a tough time hitting 4 mi./kWh. I average about 3.5 mi./kWh. I drive 45 mph for 10 straight and mostly level miles. My highest RR was 82 miles, but I float around 70 miles RR, and my furthest one-charge distance was 72 miles. This is all without any HVAC use in ~70 degree weather. I can drive 6 miles before losing my first bar on a full charge. I haven't yet done a calibration (<2 bars to full).
:idea: :idea: :idea: :!: :!:

Dropbox maintenance in progress. If any of my links aren't working after November 17, please PM me and let me know which one isn't working.

Thanks.

JoeS
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Re: Measured Wall-to-Wheels Consumption

Mon May 06, 2013 1:31 am

PV1 wrote:Does tire pressure from stock to 55 psi have a big impact? I haven't measured my tire pressure yet, but I'm running on where they were at the dealer. I also use coasting and regen like they should be used, but I have a tough time hitting 4 mi./kWh. I average about 3.5 mi./kWh. I drive 45 mph for 10 straight and mostly level miles. My highest RR was 82 miles, but I float around 70 miles RR, and my furthest one-charge distance was 72 miles. This is all without any HVAC use in ~70 degree weather. I can drive 6 miles before losing my first bar on a full charge. I haven't yet done a calibration (<2 bars to full).
PV1, if you drive 45mph without leadfooting you should be able to achieve well over 4miles/kWhr, since speed is the primary mileage-robber. Try never letting the red needle get out of the green zone on the power meter and coast wherever possible. A fully-charged RR of 82 is quite good and was probably around 5 miles/kWhr if you had measured your input. Based on my experience with my Gen1 Honda Insight, I personally believe that my running 60psi helps significantly but I have yet to be able to quantify this. Realizing that Mitsubishi specifies 36psi and a tire maximum sidewall rating is 51psi, I cannot recommend otherwise. Have fun!
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

JoeS
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Re: Measured Wall-to-Wheels Consumption

Mon May 06, 2013 1:47 am

benswing wrote:Of 439mi tracked I used 155.1kWh to charge giving me:
2.83mi/kWh
353Wh/mi on average

JoeS, recently the "elephant in the room" has been called out as being unlikely. Apparently Lithium Ion batteries may last longer than estimated.

Excerpt: ”Lithium-ion batteries should perform better because they have fewer impurities,” he said. “So the degradation will not be as fast.” He added that electronic battery management is simpler and more reliable if material quality is more consistent from cell to cell."

http://www.designnews.com/document.asp? ... ut=article


Wow, benswing, that's quite a mouthful! What did you mean that I had been "called out as being unlikely" and what does battery lifetime and that article you referenced have anything to do with energy consumption?

-----------------------------------

EDIT 16 May, 2013: I had completely misunderstood what benswing was saying and apologize for the above remark. A new thread has been created to discuss Operating Costs, as that was the context of a previous post that benswing was referring to:

http://myimiev.com/forum/viewtopic.php?f=9&t=1554

-----------------------------------

I've published the summary spreadsheet of all the data I took last year and be happy to share all the detailed backup with anyone interested as I literally measured every single watthour my iMiEV consumed. Although my wife's driving is conservative, I consider my own driving as being a mixture ranging from enthusiastic to hypermiling, primarily determined by how far I'm going.
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

joev
Posts: 52
Joined: Sun Jul 01, 2012 3:07 am
Location: Long Island, NY

Re: Measured Wall-to-Wheels Consumption

Mon May 06, 2013 6:13 am

joev wrote:7/31/12
Not a lot of miles yet but this is what I have so far:
428 miles (689km)
79kWh used
80% of the driving is 20-35 mph (32-56 kmph).

Average 5.4miles/kWh (8.7km/kWh)
Average 0.185kWh/mi (0.116kWh/km)
Average 18.46kWh/100mi
Average 11.56kWh/100km

8-31-12
Status quo, all my averages are just about the same as last month.
730 miles (1175km) lifetime
134kWh used lifetime

I am now driving in "B" mode (was driving in "D" and "Eco" in the above stats) and /I can see a slight increase in efficiency.
I would not call it a hyper-mile technique but instead of just coasting to a stop I control the braking (slowing the car down) by adjusting the pressure on the accelerator pedal. If I need a greater stopping distance I keep some pressure on the pedal; less stopping distance I ease off the pedal and get more regen.

I keep a monthly and cumulative lifetime average so I will report next month if the "B" mode makes any difference.

9-30-12
And the winner is......B mode. It did make a slight improvment overall.
Averages for the month:
Average 5.7miles/kWh (9.17km/kWh)
Average 0.176kWh/mi (0.109kWh/km)
Average 17.6kWh/100mi
Average 10.9kWh/100km

1303 miles (2097km) lifetime
235kWh used lifetime


Update:
3237 miles (5208km) lifetime
605 kWh used lifetime
Average 5.4miles/kWh (8.6km/kWh)

Still LOVING it!

Barbagris
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Location: Bilbao, Spain

Re: Measured Wall-to-Wheels Consumption

Mon May 06, 2013 7:44 am

15,4 kwh/100 km, or
6,5 km/kwh, or
4,1 mi/kwh

I live in a hilly area, and +100 km/h (65 mph) climbing, is a battery eater.
...learning...

acensor
Posts: 340
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Location: Southern Oregon

Re: Measured Wall-to-Wheels Consumption

Mon May 06, 2013 8:42 am

Re the phrase from Benswing --

"JoeS, recently the 'elephant in the room' has been called out as being unlikely. Apparently Lithium Ion batteries may last longer than estimated...."
which Joe took a bit of objection to:

I THINK I might be able to clear up some confusion and misattribution.

The "elephant in the room" was MY phrase, not Joe's, in my previous post here.
I had used it to refer to the potential hidden cost per mile of amortizing potentially high battery replacement cost (with possibilities of having to pay $10,000+ replacement costs in amortized over 100,000 miles).... I dragged that sideways into the wall to wheels consumption discussion as indirectly relevant in that our really attractive looking out-of-pocket per mile power consumption costs had that hidden aspect.
So if there's correction due (in the sense of longevity looking better than expected per beswing's post, or a slap on the wrist for bending off-topic, it's me, not Joe, or benswing who should get those. ;)

Alex
Alex
{this message posted with 100% post consumer recycled electrons}
SE 2012 white with blue trim, powered by PV plus hydro
2001 Subaru Forester L
Two Trek street/trail bicycles optimized for mild around town use

JoeS
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Re: Measured Wall-to-Wheels Consumption

Mon May 06, 2013 11:34 am

Alex, thank you for the clarification and, benswing, sorry for my misunderstanding.

We have other threads for addressing 'true' vehicle operating costs.

Let's keep this thread for people posting their actual wall energy use per distance traveled, as it's interesting to see if there is any trend for us 'real' users.
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

benswing
Posts: 47
Joined: Tue Feb 05, 2013 6:35 pm
Location: Montclair, NJ

Re: Measured Wall-to-Wheels Consumption

Mon May 06, 2013 9:11 pm

Acensor, thanks for clearing that up. Sorry if I offended someone. Since someone brought up the battery replacement concern, I wanted to share that article.

I'm with JoeS in terms of wanting to see trends in usage. I've been tracking the usage of my Zero S for over a year and now have a good sense of range based on speed and temperature. Haven't had my iMiEV long enough to get the same info, yet.
Driving Electric since 2007: Vectrix VX1 - 2007-2010, Zero S ZF9 - 2012-Present, Mitsubishi iMIEV - 2013 - 2015

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