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evnow
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Delivery Date: 25 Feb 2011
Leaf Number: 303
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Re: Miles per kwh so far... my calcs vs. the LEAFs calcs

Mon Mar 07, 2011 1:53 pm

I'm keeping track of 3 efficiencies.

1. Wall to wheels as shown by Blink
2. Efficiency shown by Leaf
3. Efficiency and kwh shown by Carwings

1 & 2 - are close to each other, after discounting the charging inefficiency from 1.

2 & 3 should match. There is no reason why they shouldn't. But they don't match. Carwings is more optmistic by 10% to 35%. After gathering a week of stats, I'll call Leaf CSR and lodge a bug.
1st Leaf : 2/28/2011 to 5/6/2013
2nd Leaf : 5/4/2013 to 3/21/2017
Volt : 3/25/2017 to 5/25/2018
Model 3 : 5/10/2018 to ?

DaveinOlyWA
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Delivery Date: 16 Nov 2019
Leaf Number: 319862
Location: Olympia, WA
Contact: Website

Re: Miles per kwh so far... my calcs vs. the LEAFs calcs

Mon Mar 07, 2011 2:08 pm

Carwings also ignores the power used by accesories as well. The wall obviously cannot.
either way your method cannot be used as e en a basic guideline. Track your charging over a week at least a month would be better. I do 120 charging and a stage similar numbers and my charging from the wall is around 3.2 AMPK
2011 SL; 44,598 mi, 87% SOH. 2013 S; 44,840 mi, 91% SOH. 2016 S30; 29,413 mi, 99% SOH. 2018 S; 25,185 mi, SOH 92.23%. 2019 S Plus; 16,686 mi, 92.44% SOH
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edatoakrun
Posts: 5222
Joined: Thu Nov 11, 2010 9:33 am
Delivery Date: 15 May 2011
Leaf Number: 2184
Location: Shasta County, North California

Re: Miles per kwh so far... my calcs vs. the LEAFs calcs

Mon Mar 07, 2011 2:10 pm

akohekohe wrote: Where I live electricity is $0.27 /kWh at the moment. So the 2.8 miles/kWh translates to 0.095 $/mile. I traded in my 2002 VW Golf TDI for the LEAF. It got 42 miles/gal. Currently Diesel is $3.88/gal here so that comes out to 0.092 $/mile. So, my fuel costs are slightly more per mile by going with the electric car. So much for the electric car yielding fuel savings!

Question:

These results are based on using the level 1 trickle charger. Is there any reason to believe my results will be any better using the level 2 charger (I don't have an easy way to measure the current consumed by my level 2 charger)?
Did you expect fuel cost savings, paying 27 cents per kWh?

The great benefit to grid efficiency and lower fuel costs of EV's only occur if owners charge off- peak, and utilities charge rates that pay them to do it. I assume the 27 cent figure is not a time-of-use rate?

If so, ask your utility why you don't get one. Or, if you want revenge, only charge at peak-demand periods. This will cause your utility to take a loss, even charging you the 27 cent rate.

Here in North California, Diesel is now over $4, and gas is nearly there. And (PG&E) off-peak power is 6 cents a kWh, so the cost comparison is quite a bit different.

I would appreciate it if someone could do an accurate L1/L2 charge efficiency comparison. If it's a significant discrepancy, I might want to start shopping for a L2 EVSE.
no condition is permanent

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garygid
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Joined: Wed Apr 21, 2010 8:10 am
Delivery Date: 29 Mar 2011
Leaf Number: 000855
Location: Laguna Hills, Orange Co, CA

Re: Miles per kwh so far... my calcs vs. the LEAFs calcs

Mon Mar 07, 2011 2:18 pm

I believe CARWINGS does include the power for accessories, and Heat/Cool (used while driving). Power used for pre-heat/cool is when the LEAF is "Off", so is probably not included.
See SOC/GID-Meter and CAN-Do Info
2010 Prius
2011 LEAF, 2014 Tesla S85
2018 & 2019 Tesla Model 3
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DeaneG
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Leaf Number: 594
Location: Cupertino, CA

Re: Miles per kwh so far... my calcs vs. the LEAFs calcs

Mon Mar 07, 2011 2:28 pm

edatoakrun wrote:... And (PG&E) off-peak power is 6 cents a kWh, so the cost comparison is quite a bit different...
If you are going to quote low off-peak rates, you also have to mention the very high on-peak rates which your daytime household electricity usage will be billed at under that plan. Driving may then seem cheap, but your home's air conditioner will be very expensive. You need to consider that as a cost of charging too.
White SL w/L3, 3kWDC Solar PV

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akohekohe
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Location: O'ahu

Re: Miles per kwh so far... my calcs vs. the LEAFs calcs

Mon Mar 07, 2011 2:33 pm

edatoakrun wrote:
Did you expect fuel cost savings, paying 27 cents per kWh?

The great benefit to grid efficiency and lower fuel costs of EV's only occur if owners charge off- peak, and utilities charge rates that pay them to do it. I assume the 27 cent figure is not a time-of-use rate?

If so, ask your utility why you don't get one. Or, if you want revenge, only charge at peak-demand periods. This will cause your utility to take a loss, even charging you the 27 cent rate.

Here in North California, Diesel is now over $4, and gas is nearly there. And (PG&E) off-peak power is 6 cents a kWh, so the cost comparison is quite a bit different.

I would appreciate it if someone could do an accurate L1/L2 charge efficiency comparison. If it's a significant discrepancy, I might want to start shopping for a L2 EVSE.
I actually will get the first 1,000 or so kWh free since I have a reverse metering agreement and last year, before I got the leaf, I produced 1,030 kWh more than I used (which the utility got to keep). So I should be able to drive around 3,000 miles for free so it is still a good deal for me but not for most people here. The utility does have a program for electric vehicles (I can't use it because of the reverse metering arrangement) that cuts about $0.06 / kWh off the rate but that still leaves you at $0.21 AND there are significant installation costs, $2,000 or so, which will make the payback take about 100,000 miles.

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evnow
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Joined: Thu Apr 22, 2010 11:41 am
Delivery Date: 25 Feb 2011
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Location: Seattle, WA

Re: Miles per kwh so far... my calcs vs. the LEAFs calcs

Mon Mar 07, 2011 3:09 pm

Hawaii is one of the few states where solar makes sense at current PV costs.
1st Leaf : 2/28/2011 to 5/6/2013
2nd Leaf : 5/4/2013 to 3/21/2017
Volt : 3/25/2017 to 5/25/2018
Model 3 : 5/10/2018 to ?

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garygid
Gold Member
Posts: 12469
Joined: Wed Apr 21, 2010 8:10 am
Delivery Date: 29 Mar 2011
Leaf Number: 000855
Location: Laguna Hills, Orange Co, CA

Re: Miles per kwh so far... my calcs vs. the LEAFs calcs

Mon Mar 07, 2011 3:15 pm

PV is rather compelling in CA also, since our e-rates are mostly in the 13 to 33 cents range, and not likely to go down.
See SOC/GID-Meter and CAN-Do Info
2010 Prius
2011 LEAF, 2014 Tesla S85
2018 & 2019 Tesla Model 3
PU: SDG&E
Solar PV: 33 x 225W -> 7 kW max AC
Craigslist: Xm5000Li Electric Motorcycle

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DeaneG
Posts: 1110
Joined: Tue May 04, 2010 9:20 pm
Delivery Date: 01 Apr 2011
Leaf Number: 594
Location: Cupertino, CA

Re: Miles per kwh so far... my calcs vs. the LEAFs calcs

Mon Mar 07, 2011 4:26 pm

garygid wrote:PV is rather compelling in CA also, since our e-rates are mostly in the 13 to 33 cents range, and not likely to go down.
... especially after you add the EV usage, many people will be solidly into the highest rate tier in the summer.
White SL w/L3, 3kWDC Solar PV

edatoakrun
Posts: 5222
Joined: Thu Nov 11, 2010 9:33 am
Delivery Date: 15 May 2011
Leaf Number: 2184
Location: Shasta County, North California

Re: Miles per kwh so far... my calcs vs. the LEAFs calcs

Mon Mar 07, 2011 5:03 pm

DeaneG wrote:
edatoakrun wrote:... And (PG&E) off-peak power is 6 cents a kWh, so the cost comparison is quite a bit different...
If you are going to quote low off-peak rates, you also have to mention the very high on-peak rates which your daytime household electricity usage will be billed at under that plan. Driving may then seem cheap, but your home's air conditioner will be very expensive. You need to consider that as a cost of charging too.
Well, I've posted this info so many times, I thought everybody would be sick of it, but since you ask, the complete tariffs,including E1 and E9 rates are here:

http://www.pge.com/tariffs/ERS.SHTML#ERS

If I buy an EV and change from E1 to E9A, I expect my average kWh cost to decrease from about 12.2 to 9 cents per kWh, under 6 cents for the EV, and 11-12 cents for the rest of my home. I will have additional cost savings, by heating my home and water with my geothermal heat pump (rather than propane) at the (now reduced to 6.2 cents a kWh) winter off-peak rate.

Single meter time-of-use gives you the greatest benefits if you make the same energy efficiency efforts in your home, as you do with your vehicle.

And you are correct, in that air conditioning load is the single biggest driver of not only of individual bills, but total grid electricity peak costs, in most of the US.
no condition is permanent

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