A real-life cost of Leaf driving calculation in Bay Area

[nosuchthing]

I just got my electric bill so I whipped out the calculator just to see if we're saving any money on Leaf driving, and particularly how much.

Turns out we used 20 kW extra power per day (Leaf). Translates to about 72 miles of driving Leaf. I get 3.6 average and cannot get any higher -- it's all freeway at 65 and higher.

My avarage cost per kW comes to 21.3 cents winter juice as compared to 26.8 cents summer juice. PG&E charges more in summer than in winter in case you haven't noticed on your bill. They get you good particularly on top tier on-peak rate of 50 cents per kW.

So, 21.3 c/kW x 20 kW comes to $4.26 driving 72 miles. If it was an ICE with 28 mpg the cost would be (at $3.60 gas) $9.26. Five bucks savings per day amounts to $150 a month plus about 5 bucks per month for oil changes (every 3 months - I do it myself and always get $2 oil on sale). Not too shabby even with PG&E predatory pricing and no real breaks for us Leaf owners.

As far as the summer juice, it is 26.8 c/kW x 20 kW which comes to $5.36 that translates to savings of $3.90 per day or $117 per month. Not as flashy but money nevertheless. Plus 43 lb of Carbon savings as well, calculation based on 60 lb net value per 100 miles driven (90 lb ICE vs. 30 lb Leaf juice generation).

My next step in a year or two is 8-10 kw solar shingles (DOW Powerhouse) and second electric with a bigger range. That means free, clean driving, and anytime washer dryer, i.e. no more TOU (time of use).

 

[KJD]

My next step in a year or two is 8-10 kw solar shingles (DOW Powerhouse) and second electric with a bigger range. That means free, clean driving, and anytime washer dryer, i.e. no more TOU (time of use).

The solar shingles look nice, but last time I looked they were pretty pricey. I was thinking more along the lines of a conventional panel system for my next upgrade. Has anyone here done biz with sunelec ?

http://www.sunelec.com/index.php?main_page=pv_systems&id=1052&type=GT" onclick="window.open(this.href);return false;

 

[DaveinOlyWA]

glad to see it adds up in your favor. i was under the impression that anyone could get a separate meter for EV charging during super off peak (for a price naturally) to get the best rates for juicing up the Leaf.

but Solar is really the way to go. most people see a return on solar in 15 years but if plugging in a car and weighing the difference in fuel costs, it cuts payback to 5-7 years or less.

check out my signature. almost a 3 to 1 advantage in cost over a 50 mpg Prius but my juice runs me 10.4 cents.

 

[thankyouOB]

I just got my electric bill so I whipped out the calculator just to see if we're saving any money on Leaf driving, and particularly how much.

Turns out we used 20 kW extra power per day (Leaf). Translates to about 72 miles of driving Leaf. I get 3.6 average and cannot get any higher -- it's all freeway at 65 and higher.

My avarage cost per kW comes to 21.3 cents winter juice as compared to 26.8 cents summer juice. PG&E charges more in summer than in winter in case you haven't noticed on your bill. They get you good particularly on top tier on-peak rate of 50 cents per kW.

So, 21.3 c/kW x 20 kW comes to $4.26 driving 72 miles. If it was an ICE with 28 mpg the cost would be (at $3.60 gas) $9.26. Five bucks savings per day amounts to $150 a month plus about 5 bucks per month for oil changes (every 3 months - I do it myself and always get $2 oil on sale). Not too shabby even with PG&E predatory pricing and no real breaks for us Leaf owners.

As far as the summer juice, it is 26.8 c/kW x 20 kW which comes to $5.36 that translates to savings of $3.90 per day or $117 per month. Not as flashy but money nevertheless. Plus 43 lb of Carbon savings as well, calculation based on 60 lb net value per 100 miles driven (90 lb ICE vs. 30 lb Leaf juice generation).

My next step in a year or two is 8-10 kw solar shingles (DOW Powerhouse) and second electric with a bigger range. That means free, clean driving, and anytime washer dryer, i.e. no more TOU (time of use).

dont you save on bridge tolls?

 

[cwerdna]

So, 21.3 c/kW x 20 kW comes to $4.26 driving 72 miles. If it was an ICE with 28 mpg the cost would be (at $3.60 gas) $9.26. .

My lifetime average on my 06 Prius ~45 mpg. So, at $3.60/gal gas, that trip would be $5.76.

glad to see it adds up in your favor. i was under the impression that anyone could get a separate meter for EV charging during super off peak (for a price naturally) to get the best rates for juicing up the Leaf.
...
check out my signature. almost a 3 to 1 advantage in cost over a 50 mpg Prius but my juice runs me 10.4 cents.

Yeah, but getting the separate meter means spending even more money.

Those in WA, esp. Seattle City Light customers are blessed w/cheap electricity.

dont you save on bridge tolls?

Depends. See http://www.bayareafastrak.org/static/facilities/index.shtml" onclick="window.open(this.href);return false;. For me, it'd near worthless. I live nowhere near any of the bridges and have almost never needed to cross them. During a 5.5 year span, I believe I've crossed any toll bridge <5 times.

 

[vgniphone]

Here in Portland, Oregon power is around .11 KWH, so 5000 miles cost me about $120.00.

 

[thankyouOB]

$275 for the Leaf
vs.
$2400 for my ICE, which got 23 mpg, figuring gas at $4 a gallon.

that leaves out the fact that my solar powers the Leaf 10 months a year, leaving me to pay about $40 a year.

of course, the solar cost 10k, but $40 covers my car and all power in the house.

 

[nosuchthing]

As far as "The solar shingles look nice, but last time I looked they were pretty pricey."

These are a different (older) product. DOW shingles are actually cheaper than panels. The shingles contain no silicon, that's why they supposedly run down to about 60% of the cost of panels. They are somewhat less effective -- by about 10%. All you have to do is increase the square footage to get the kWs. I've got plenty of roof space for that.

"Dow claims that solar shingles could be 10-15% cheaper than a rack of panels (per watt) and as much as 40% cheaper than a fully installed and tied-in solar system." (see link below)

http://solar.calfinder.com/blog/products/dow-hopes-to-light-the-way-in-solar-shingles/" onclick="window.open(this.href);return false;

As far as the PG&E, I refuse to put up another annoying meter (a smart meter of all things) on my outside wall. This is a lame and dubious savings offer. The math just doesn't add up. Fact is, Bay Area has perhaps the most expensive electricity in the US. My motto is: don't get angry, get even. Once DOW floods NorCal with the shingles PG&E will become a marginal gas company fixing copper lines and not prices.

 

[cwerdna]

Fact is, Bay Area has perhaps the most expensive electricity in the US.

Might not be... take a look at the tables available from http://www.eia.gov/tools/faqs/faq.cfm?id=507&t=3" onclick="window.open(this.href);return false;. Compare CA prices to some others.

Some more electricity price links are at http://www.mynissanleaf.com/viewtopic.php?p=158814#p158814" onclick="window.open(this.href);return false;.

 

[mark57]

For us it made total sense. Went solar several years ago (7,200 watt system). With 2 kids home, my wife and I zeroed out our PG&E electric bill each year. Now that both kids are gone, we have been generating significantly more power per year than we use (last year our "true up" with PG&E was negative $ 480). Rather than just giving the power back to PG&E for free (PG&E uses a different way to calculate when they pay you than how they calculate when you owe them money for electricity), we got a Leaf. Even with the Leaf, we calculate we won't use up our surplus with PG&E each year. For us, getting a Leaf just eliminated the $ 200+ per month we had been spending on gas.

If you have solar power at home, you should really seriously consider an electric car.

 

[matth]

Turns out we used 20 kW extra power per day (Leaf).

My avarage cost per kW comes to 21.3 cents....

You probably mean per KW-hr in each of these cases.

 

[DeaneG]

....My avarage cost per kW comes to 21.3 cents winter juice as compared to 26.8 cents summer juice. PG&E charges more in summer than in winter in case you haven't noticed on your bill. They get you good particularly on top tier on-peak rate of 50 cents per kW....

I used the incremental rate rate than the average, because that's what you are actually paying to drive the car (incremental kWh for charging the car). Using the average electricity rate instead hides part of the charging cost as household electricity use, which isn't right.

At 50 cents per kWh tier rate, and 3.6 miles/kWh, that's the same as a 25mpg ICE car at $3.50 per gallon. What is your actual tiered rate per kWh in the summer (check if added energy use for charging will move you up a tier from last summer)?

Also, if you see 3.6kWh on the instrument cluster display, you need to multiply that by about 0.85 to get wall to wheel efficiency. If so, you'd be around 21mpg ICE equivalent at a $0.50/kWh tier rate. I wasn't sure if you calculated the 72 miles from the instrument panel mi/kWh, or an actual mi/kWh from the odometer miles.

 

[Deleted member 3147]

As far as "The solar shingles look nice, but last time I looked they were pretty pricey."

These are a different (older) product. DOW shingles are actually cheaper than panels. The shingles contain no silicon, that's why they supposedly run down to about 60% of the cost of panels. They are somewhat less effective -- by about 10%.

That is a deceptive comment. The page you linked to states that the DOW shingles are about 10% efficient, vs. as much as 18% for panels. Even if we take 15% as typical for panels, the shingles are 33% less efficient!

I'm not arguing that they aren't good and possibly cheaper per KW, I'm just objecting to your 10% number.

 

[nosuchthing]

DeaneG, it was not meant to be a scientific calculation, just an average assessment. The car says my m/kW is 3.6 so I figure if I used 20 kW more per day than year ago without Leaf it's a good indicator of my approximate average mileage per day (3.6 x 20 = 72 miles per day).
Let's just call it savings of $3.50 to 5.50 per day, eh? My main concern is not the hundred bucks or more (or less) savings, but making sure Leaf gets driven by the household, and the fact that I don't have to change oil as often and my carbon footprint is reduced.

 

[Burnszilla]

I called PG&E on friday and told them I was buying an EV. They have two discounted rate plans for EV owners E-9A and E-9B. E-9B requires the addition of a separate meter and panel for the EV charger, so I went with the simple E-9A rate. Our off peak rate dropped from 12c /kWh to 4c /kWh!

 

[DaveinOlyWA]

I called PG&E on friday and told them I was buying an EV. They have two discounted rate plans for EV owners E-9A and E-9B. E-9B requires the addition of a separate meter and panel for the EV charger, so I went with the simple E-9A rate. Our off peak rate dropped from 12c /kWh to 4c /kWh!

4 cents? is there an extra connect charge or something to process the EV? or is the 4 cents applicable to household electricity as well?

if so, that would be unbelievable!

 

[DeaneG]

...4 cents? is there an extra connect charge or something to process the EV? or is the 4 cents applicable to household electricity as well? if so, that would be unbelievable!

That rate does cover household use too, but the daytime rates are correspondingly higher to average out at a more typical cost. E9A does get very expensive in the summertime with heavy A/C use - up to $0.54 per incremental kWh for average electricity consumption in my neighborhood.

E9A can be a great deal if you manage your summer afternoon electricity usage carefully, or have enough solar PV installed. At least while that rate lasts.

 

[BLUEH20]

This is a rea-life cost of LEAF driving in Douglas County, Washington.

Our LEAF was purchased on 19 May 2011 and presently has more 4004 miles on the clock.

Our power provider has only one residential rate, no specality charges and is soley based on hydroelectric power generation.

Our cost for electricity is $.0208/KWH. Our LEAF averages 3.6 miles/KWH at the 120 VAC wall receptacle. That equates to $.0058 per mile. Our previous internal combustion engine (ICE) daily vehicle averaged 18.5 miles/gallon. At $3.50/gallon that is $.1892/mile. The ICE vehicle fuel cost per mile is 32.62 times more costly than the LEAF.

 

[cwerdna]

Our power provider has only one residential rate, no specality charges and is soley based on hydroelectric power generation.

Our cost for electricity is $.0208/KWH.

Are you serious? It's just barely over 2 cents per kwh??? Do you have a link to your utility's electric rates?

That sounds almost too good to be true.

 

[veeoo]

I called PG&E on friday and told them I was buying an EV. They have two discounted rate plans for EV owners E-9A and E-9B. E-9B requires the addition of a separate meter and panel for the EV charger, so I went with the simple E-9A rate. Our off peak rate dropped from 12c /kWh to 4c /kWh!

Make sure you read and understand the hours for peak, partial-peak, and off-peak. With the E9 rates, the peak and partial-peak hours are quite extensive. During those times you'll be paying more for your household electricity compared to the E1 rate you were probably on before. That's especially true if you go into the higher tiers above 101% or above 130% of the baseline.

http://www.pge.com/tariffs" onclick="window.open(this.href);return false;