Lifetime Average Wh/mi

[dmckinstry]

I haven't posted in this thread in ages, but my car is just a day or two after its one year anniversary. Here's the latest Wh/mi screen shot.

My mileage is much worse since heading to so. CA last December. For one thing I do much poorer on highway miles. Also, most of the driving down there has been done with four people in the car (average passenger weight over two hundred pounds). Before going the Seattle last week, the average for the Trip Meter A was down to 283 or even briefly down to 282. After getting back, it was back up to 285. As you can see, it's back down to 284. However, the lifetime average is down to 298, although it was at 299 before leaving. I think it is improving a bit with the weather getting warmer again.

 

[Jeff Miller]

so where were we going wrong in the previous posts when we all seemed to agree that the average losses were in the 16-17% range? or your previous post where you were seeing 20% charging losses + 2kwh of vampire? Just small sample size? variance in vampire numbers? variance in car to "wheel" efficiency? that last one we should at least be able to give some guidance on based on the info collected in this thread.

If you look at the outliers on the plot of phx182flyer's data above, they are mostly observations that include more than one day of data. For example, the pink point at 110 miles and energy 65 kwh is an observation that covers six days of driving. It makes sense that this point is above most of the other points because there are six days of vampire draw rather the typical orange point's one day. If you don't include the 'days' variable in the regression, the slope of the 'miles' variable will be somewhat higher than it 'should' be because it's pulled up by these outliers. Including 'days' as a variable in the regression corrects for this, so is I think probably somewhat more accurate, at least as far as the coefficient of the 'miles' variable is concerned. (Note that the energy ~ miles + days regression above assumes a zero intercept so has the same number of variables as the energy ~ miles + constant regression; I'm wondering if I should have also included a non-zero constant to account for things that are uncorrelated to days and miles like pre-heating the car).

That said, I checked my own wall energy use over the last 450 days. If I assume a charging loss of 11.6% on top of the energy use the car reports and use a 3.35 vampire loss, I get an wall energy number that is 15% larger than what I actually got. So this regression doesn't quite work for me (phxflyer's original regression actually works better). I believe my vampire losses are lower than 3.35 per day. We I think we would need to look at more data sets to nail this down.

 

[dirkhh]

May: dirkhh 303 782 OR 60 19
Life: dirkhh 325 15098 OR 60 19

I think this was my best month so far (and one of the lower miles driven ones as I was in Asia for almost two weeks)

An even lower "miles driven" month (again out of town a lot). Next month will be dramatically different with the trip to TMC Connect

And an even better average - my best, yet, first time below 300 for a month.

June: dirkhh 297 634 OR 60 19
Life: dirkhh 324 15733 OR 60 19

 

[gg_got_a_tesla]

A so-so month for my CA 60 19", ending at over 301 Wh/mile for the month given heavy use of AC and lots of highway miles. Lifetime's at 308 still:

 

[dirkhh]

A so-so month for my CA 60 19", ending at over 301 Wh/mile for the month given heavy use of AC and lots of highway miles. Lifetime's at 308 still:

I'm pretty sure that's the first month where my average is below yours, gg_got_a_tesla...

 

[Bugeater]

A bit higher this month. Maybe showing off the car at my new job!

 

[Al Sherman]

My June and Lifetime numbers:

June: Al Sherman 273 1186 IN P85 19 1

Life: Al Sherman 305 13,754 IN P85 19 1

 

[mibaro2]

My numbers for this month. Overall going down, but noticing the a/c usage.

June 2403.2mi , 668.5kwh , 278 wh/mi
life 5757.7mi , 1680.3kwh , 292 wh/mi


June 3867.6 km , 668.5 kWh , 173 wh/km
life 9266 km , 1680.3 kWh , 181 wh/km

 

[efusco]

Decent month, but I don't think my lifetime average dropped. Not a surprise given that I passed 33k miles this month.

edit: Just checked. I finished May with a lifetime 314 Wh/mi, so I dropped to 313 Wh/mi lifetime. The progress downward will be slower and slower...but hopefully the increases in lifetime will be slower come winter too.

 

[Klaus]

June 2014 + lifetime

 

[paco3791]

June = A, Lifetime = B

 

[jerry33]

 

[Brass Guy]

June numbers:
1,749.9 mi, 267Wh/m

Lifetime:
20,549 mi, 304Wh/m

Still on original tires, probably half way through.

 

[Benjamin Brooks]

How the heck do you get better than ideal range ("55mph on flat surface") energy usage average after 27K miles!?! Do you drive 40mph behind a semi truck everywhere you go?

View attachment 52798

 

[ZBB]

Here's my update... I went ahead and reset Trip B at the beginning of June. Decided to use Trip B for an annual reset of lifetime, so my Lifetime number is now calculated on my tracking spreadsheet...

Lifetime:
ZBB 294 18,065 AZ 60 19 1 6/30/14

June by itself was 288 over 1,323 miles. That was 270 miles less and 23 Wh/mi lower than June 2013 (we moved offices earlier this year, so my commute is about 10 miles a day shorter, which explains most of the fewer miles)...

I believe there are a couple factors impacting the reduced Wh/mi this year vs last year:
- June '13 was my first month with the car, so I've learned to drive it more efficiently in the last year
- June '14 was cooler than last year -- a good chunk of the month was in the low 100s vs 5-10 degrees warmer, especially the 2nd half of last June (we had over a week of 112+ last year in June)
- The drive unit was replaced in late Feb -- the new one is more efficient (March-May were ~10 Wh/mi lower than the previous 3-4 months)
- Temps do impact Wh/mi -- commute home for most of June was 100-105 most days, vs 90-95 in May and 80s in April. June was 288, vs 284 the prior couple months. That's not a bad impact so far (although the last few days have gotten closer to 110 -- and I lose ~3 rated miles just to cool the car down from ambient to 71 (when pre-cooling, also notice it over the first mile if I don't pre-cool)...

 

[kendallpb]

Yay, it's gone down a bit; thanks, trip-to-Boston. ;-) As usual, "A" is my near-lifetime and "B" is the past month. And look, my monthly dropped from 318 to 302. (Last month I mislabeled the month.)

ONE-MONTH:
kendallpb 07-01-2014 302 2,021 MD S85 19" (June)

LIFETIME:
kendallpb 11-09-2013 325 11,699* MD S85 19"
kendallpb 12-01-2013 328 12,596 MD S85 19"
kendallpb 01-03-2014 333 14,460 MD S85 19"
kendallpb 02-01-2014 338 15,637 MD S85 19"
kendallpb 03-02-2014 341 17,326 MD S85 19"
kendallpb 04-02-2014 342 18,230 MD S85 19"
kendallpb 05-01-2014 341 19,825 MD S85 19"
kendallpb 06-01-2014 338 22,008 MD S85 19"
kendallpb 07-01-2014 335 24,029 MD S85 19"

 

[mknox]

June 2014 numbers:

Month:
3,090.5 miles
887 kWh
287 Wh/mi

Lifetime:
29,544.3 miles
10,018 kWh
339 Wh/mi

I do not have actual "power out of the wall numbers" for June. I took a trip and used Level 2 chargers and Superchargers along the way and didn't record the energy from them.

 

[jerry33]

How the heck do you get better than ideal range ("55mph on flat surface") energy usage average after 27K miles!?! Do you drive 40mph behind a semi truck everywhere you go?

LOL. I never tailgate, especially not trucks. It's about choosing when to go fast and when not to. Keeping some air in your tires doesn't hurt either.

 

[efusco]

How the heck do you get better than ideal range ("55mph on flat surface") energy usage average after 27K miles!?! Do you drive 40mph behind a semi truck everywhere you go?

Jerry and a couple other guys are freaks of nature with their ability to achieve those numbers. I've done a bit of hypermiling and, at times, can match their numbers under ideal conditions, but a combination of type A personality, a car that begs me to drive it fast, and some pretty untoward commutes and weather keep my lifetime in that 313 +/- range. I hope to visit with Jerry someday near his home and 1)watch him drive, and 2) drive his usual routes and see if I can come close to his numbers.

 

[MichaelS]

End of June update.

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