The REAL Charging Cost per SDG&E and "Equivalent ICE mpg"

[electricfuture]

I am supposed to receive my April delayed Leaf in June. In the mean time I have been working here in San Diego with ECOtality and SDG&E to obtain the best charging rate available. What I found was deceptive billing which greatly increases your real charging cost. On the plus side I am now applying an equivalent cost of fuel per 100 miles for my current ride to see the “real” mpg rating of the Leaf – which is also surprising in a positive way.

First let’s look at SDG&E’s billing deception. They have has several rates for homes.

SDG&E standard tiered rates.
Your bill shows a rate per kWh that is incomplete. The published rate on your bill does not include: Bond Charges-$0.00515/kWh, Summer Generation Charges -$0.08978 (higher charge in winter), State Surcharge tax - $0.00022/kWh and a State Reg. Fee $0.000240/kWh regardless of which tier they are apart. This adds $0.09539/kWh to your rate. The table below shows the REAL rates with this addition:
Tier --------- Published rate/kWh / Real Rate/kWh
1-298kWh----- 0.03919 / $0.13458
2-next 89kWh- 0.05996 / $0.15535
3-the rest----- 0.18708 / $0.28247

So, for most of us we would be charged $0.28247/kWh for charging the Leaf as it would be an addition to our household use of 387 kWh.

EV Rate
First you should know that the ECOtality/SDG&E special study rates (Super Off-Peak rates 12AM to 5 AM) are $0.07, $0.08 or $0.14. They will not tell you what your rate is until after you sign up. Only then a random number generator assigns your rate to you. You cannot change this or “try again”. Several of the owners are reporting the $0.07 rate – but lucky me I got the $0.14 rate!

I questioned SDG&E extensively concerning this and they explained they want to see when people will charge the car based on different rate structures and time of day. I told them that this is a no brainer – the car has a computer and will charge at night when not in use and for the lowest rate. They said they have to “prove” this to the State Regulatory Commission and hence the study.
What I also found out is that the $0.09539 additional charges outline above MUST BE ADDED to this rate. My actual rate will then be $0.23539/kWh to charge the Leaf. Here are the real Super Off Peak EV rates:
Assigned Rate / Real Rate/kWh
0.07 / $0.16539
0.08 / $0.17539
0.14 / $0.23539

EV-TOU (Time of Use) Rates
These rates are normally only for industrial/commercial high use customers, but have been made available to those who are not in the ECOtality study and must buy our own charger as well. I thought this is for me – I’ll get a Leviton Charger and signed up. I can wash clothes, dishes and charge the car at the low evening and 12AM-5AM rates and save money on my overall electric bill.
I was wrong and have switched back to the EV rate. The reason – the “Super Off Peak” rate is the SAME rate as the EV rate - $0.023539 when you add in the applicable charges – but the day rates are much higher than the Tier 1 and Tier 2 rates! So I would be getting more expensive electricity overall even if I sleep during the day and work at night!

Final Analysis:
I am going with the EV rate charging the Leaf for $0.23539/kWh on a separate meter and keeping my Tiered rate structure for the rest of my home use. This will save me about $0.05 per kWh – better than nothing!

REAL COMPARITIVE ICE MPG
Edmonds stated that the EPA rating for the Leaf is 34. You multiply this by the cost of a kWh to get cost per 100 miles.
My numbers are: Electric rate: $0.23539/kWh 34 X 0.23539/100= $8 cost of charge per 100 miles.

My Civic Hybrid gets 34 mpg here in San Diego (lots of hills).

Current cost of gas is $4.17 per gal reg. (and rising).

So, to go 100 miles I need 100/34 mpg = 2.9 gallons of gas X $4.17 = $12.09 per 100 miles

So the comparison is how far could I drive my Leaf for the same fuel cost of driving my Civic Hybrid 100 miles? $12/$8 X 100 = 150 miles! This is my true ICE comparative mpg equivalent.
In order to get your true ICE comparative mpg, just change the numbers in bold to fit your situation.
They don’t use this though because of the variables: kWh costs, gasoline cost, mpg comparisons against another vehicle’s performance vary from person to person. Note that as gas prices go up your
ICE comparative mpg gets better, although electric costs could go up as well. If your current vehicle is getting less than 34 mpg, your electric mpg would be better, same if you have a lower electric rate.

Using this formula I converted savings from oil changes and filters - say $50 with synthetic 3 times a year = another 3x$50/$8 X 100 = 3,875 BONUS miles for FREE per year. Factoring this in further increases your electric mpg as it effectively contributes cash for paying your electric bill.

Later there are tune up charges, plugs, air filters, fuel filters, mufflers, transmission flushes, etc. all adding to the BONUS free miles. Other stuff can happen because a ICE or Hybrid has a lot of moving parts. Whereas the Leaf has 2 moving parts, the motor rotor and a single gear transmission.

 

[lonndoggie]

Thanks for that, very interesting stuff.

It may be, however, somewhat better than that. Maybe.

Here's the summer Super Off-Peak values for the "X" rate (the one with the highest super off peak times):

UDC        EECC       DWR-BC      Total
$0.09810   $0.03545   $0.00505    $0.13860

The UDC value comes from another table that includes transmission, distribution, and several other acronymically-challenging sub-rate values. I'm thinking that this is the total rate--that you needn't add the $0.9539 to it, because it (or its equivalent) already has been added. Your analysis of the regular residential bill seems correct to me, however.

See this document for all the data for all three rates.

Then again, I may have that wrong, and your numbers may be correct; I find SDG&E's stuff clear as mud!

Anyone out there with an actual EV meter bill can clear this up pretty quickly.

 

[sdbonez]

What I also found out is that the $0.09539 additional charges outline above MUST BE ADDED to this rate. My actual rate will then be $0.23539/kWh to charge the Leaf. Here are the real Super Off Peak EV rates:
Assigned Rate / Real Rate/kWh
0.07 / $0.16539
0.08 / $0.17539
0.14 / $0.23539

This is the part I suspected but hadn't proven. (I get my first bill with some 2nd meter charges in 1 week). Can anyone else confirm with what they're actually seeing at this point? (makes it roughly equivalent to the DR-Tier2 rate with a 2nd meter)

 

[Randy]

Here's the detail from my latest bill...I'm in the Z group rate schedule.

I used a total of 106 kWh, 3 on-peak, 4 off-peak, and 99 during the super off-peak time periods.

Here are the charges:

Electricity Delivery = $0.26943 (on peak), $0.07137 (off peak), and $0.02806 (super off peak)
Electricity Generation = $0.06571 (on peak), $0.05965 (off peak), and $0.03732 (super off-peak)

Electricity Delivery + Generation = $0.33514 (on peak), $0.13102 (off peak), and $0.06538 (super off peak)

My charges for ED+G are: $1.01 (on peak), $0.53 (off-peak), and $6.47 (super off peak) = $8.01
DWR Bond charge = 106kWh x $0.00505 = $.54
Total Electric Charges are $8.55

There are 56 cents of taxes and fees on top of that to bring the total billed amount to $9.11, which is my total EV cost was for last month. Those taxes are as follows:

* City of San Diego Franchise fee Differential $7.80 x 5.78% = $0.45
* Franchise fees on electric energy supplied by others 0.75 x 6.88% = $0.05
* State Surcharge Tax 106 kWh x $0.000290 = $0.03
* State Regulatory Fee 106 kWh x $0.000240 = $0.03

I hope that helps to break it down for others....

 

[whoami]

What I also found out is that the $0.09539 additional charges outline above MUST BE ADDED to this rate. My actual rate will then be $0.23539/kWh to charge the Leaf. Here are the real Super Off Peak EV rates:
Assigned Rate / Real Rate/kWh
0.07 / $0.16539
0.08 / $0.17539
0.14 / $0.23539

This is the part I suspected but hadn't proven. (I get my first bill with some 2nd meter charges in 1 week). Can anyone else confirm with what they're actually seeing at this point? (makes it roughly equivalent to the DR-Tier2 rate with a 2nd meter)

From Randy's bill this looks incorrect. Its only the $0.07, $0.08 and $0.14 TOTAL rate.

If these rates are incorrect I will be contacting the PUC about the email I received about my 2nd meter rates. Their chart in the email does not include any other disclosures past the amounts above.

 

[sdbonez]

What I also found out is that the $0.09539 additional charges outline above MUST BE ADDED to this rate.

This is the part I suspected but hadn't proven.

From Randy's bill this looks incorrect. Its only the $0.07, $0.08 and $0.14 TOTAL rate.

Thanks, Randy - that helps a lot. Whoami, my concern was that the letter only talked about electricity, not distribution...but with Randy's examples, I believe this statement above is incorrect and my total on the -M rate will be ~.08/kWh in super off peak.

 

[davekern]

Total Electric Charges are $8.55

I hope that helps to break it down for others....

I am in San Diego and am getting ready for my Leaf. Out of curiosity, how may miles do you think you drove for the $8.55?
Thanks!

 

[Coffee_Slurry]

Whoami, my concern was that the letter only talked about electricity, not distribution...but with Randy's examples, I believe this statement above is incorrect and my total on the -M rate will be ~.08/kWh in super off peak.

The 'letter' from SDG&E seems to have total all-up kWh rates, minus the overall taxes and add-on surcharges that come at the end.

The confusion comes from the tariff schedule which shows only the Generation rates.

Here is the EPEV-X (high suck) schedule:
http://www.sdge.com/tm2/pdf/ELEC_ELEC-SCHEDS_EPEV-X.pdf
The "Total Rate" is the interesting one, not the "UDC Total"

Now here's the standard DR schedule:
http://www.sdge.com/tm2/pdf/ELEC_ELEC-SCHEDS_DR.pdf
NO mention of the Total Rate, just the UDC and its constituent parts.

Why, if someone read the sheet for DR-SES, they might even thing it was a good deal:
http://www.sdge.com/tm2/pdf/ELEC_ELEC-SCHEDS_DR-SES.pdf
Look at those marvelous rates! Only, it's just the UDC total.

Very confusing, very inconsistent.

 

[Randy]

I am in San Diego and am getting ready for my Leaf. Out of curiosity, how may miles do you think you drove for the $8.55?
Thanks!

I wish I had a log, but I haven't tracked my miles. Carwings tells me 349 miles during that billing period, although I realize that many times the numbers aren't accurate, especially if there's a trip or two that didn't register.

Another way to calculate is that I've had the car 15 weeks and just rolled over 1700 miles. Discounting the 100 mile trip home as a 1 time event, that makes about 1600 miles over 15 weeks or about 15 average miles per day on the car. I didn't drive the car for 4 days since we were out of town, so would be (30 x 15) - 60 or about 390 miles on average for the month.

So the actual total is somewhere between 349 and 390...Either way, the total charge of $9.11 is pretty cheap for that kind of mileage. My ICE car got around 28 MPG, so at 375 miles, that would be about 13 gallons of premium (which is now $4.38 in my neighborhood). So that's about $57 worth of gas for the month vs. $9.11 worth of LCTRICity...About 16% of the gas costs, complete with the EV grin...

I should at least start writing down the mileage at the first of each month to make the cost calcs easier in the future...

 

[mark13]

You are suppose to receive your April delayed Leaf in June? Why is it delayed until June ?

 

[DaveEV]

I should at least start writing down the mileage at the first of each month to make the cost calcs easier in the future...

SDG&E has a meter reading schedule - just mark the expected meter read dates and note your odometer then. Don't worry too much about being a day or two off - it will average out over time.

 

[Randy]

I'm on cycle 21, so my meter is read on the last or first day of any given month...

 

[stanley]

The X rate is outrageous!!! Twice the cost if you use super off peak. I thought that the purpose of the study and the incentive is to entice people to charge between midnight and 5AM in order to reduce strain on the infrastructure and use the over night electricity that is not used(wasted). Now I know why they would not tell us our rate until we are locked into the program. This is OUTRAGEOUS

 

[SanDust]

As GroundLoop pointed out, the good news is that the OP misread the rates! You pay for UDC which is I think is the "Utility Distribution Cost" or the cost of distributing the power. You also pay the EECC which I think is the "Electrical Energy Commodity Cost" or the cost of the power. IOW you pay the utility for distributing the power and for the power. In the bad old days (like last year) SDG&E only posted the UDC which was IMO very misleading, but now they post the entire rate which includes both the UDC and the EECC. http://sdge.com/regulatory/elec_residential.shtml This is much less confusing IMO.

What happened is that the OP became confused by the two different ways SDG&E publishes the rates. He took the old formula where you have to add the EECC to the published rate and applied it to the experimental EV rates which already include the EECC. This resulted in the UDC being added twice. The real super off peak rates are basically $.14, $.08, and $.07 which is what he used as the baseline. So he won't be paying as much as he thought.

As for saving money on gas, the $7500 tax credit and a $5000 state rebate will buy you over a 100,000 miles of gas even at current prices.

 

[lonndoggie]

The real super off peak rates are basically $.14, $.08, and $.07 which is what he used as the baseline. So he won't be paying as much as he thought..

Right as I'd said in the second post, and which the document I linked to showed.

What surprises me, however, is GroundLoop's assertion that the DR-SES rates are still quoted as only the partial per kWh rates. If you look at the table in the PDF he refers to, you'll note that the rate is identical all day long! And it's very low. Makes no sense.

But, if you look at this page: http://www.sdge.com/nem/rates.shtml you'll see the following:

• Summer on-peak 26.9¢ per kWh
  Summer semi-peak 19.1¢ per kWh
  Summer off-peak 17.6¢ per kWh
  Winter semi-peak 18.6¢ per kWh
  Winter off-peak 17.8¢ per kWh

What I don't know is if you need to add that constant value from the PDF to these numbers, or if these are the total per kWh rates.

 

[SanDust]

The X rate is outrageous!!! Twice the cost if you use super off peak. I thought that the purpose of the study and the incentive is to entice people to charge between midnight and 5AM in order to reduce strain on the infrastructure and use the over night electricity that is not used(wasted). Now I know why they would not tell us our rate until we are locked into the program. This is OUTRAGEOUS

Relax. Don't be seduced by percentages. You don't save much gas going from 40 MPG to 50 MPG because you're not using that much gas in the first place, and you don't spend that much going from $.07/kWh to $.14/kWh because you're not spending that much in the first place. If you use 250 kWh at $.07 that's $17.50. At the "outrageous" X rate of $.14/kWh you'd spend another $17.50.

I'm looking at $17.50 and thinking that's not a huge expense especially since you're getting a free charger and an install which is worth at least $1200. That $1200 would pay for the cost difference between the "worst" and the "best" rates for six years.

 

[SanDust]

What surprises me, however, is GroundLoop's assertion that the DR-SES rates are still quoted as only the partial per kWh rates. If you look at the table in the PDF he refers to, you'll note that the rate is identical all day long! And it's very low. Makes no sense.

The problem is that on the SDG&E web site sometimes they list just the UDC total and sometimes they include the EECC and the total rate. It's confusing as hell. I'm sure you're looking at only the UDC which is always $.11591 as shown here: http://sdge.com/tm2/pdf/ELEC_ELEC-SCHEDS_DR-SES.pdf What is so so weird is that on the same page that links to this rate which shows only the UDC the link to the Experimental EV rates show the "Total Rate". Go figure.

The only saving grace is that the charts usually say "UDC Total" or "Total Rate". But you have to know what your'e looking at. FWIW I didn't think the DR-SES had tiers. That's news to me.

 

[Coffee_Slurry]

That's exactly the point -- SDG&E is inconsistent and confusing because they mix statements about UDC rates in one place, EECC in others, and Total in some of the communication. They often leave the rest of the information totally absent, and represent it yet another way on your bill! It's almost impossible to compute your own energy bill.

The EV Letter is "Total", as are the EPEV-X/Y/Z schedules. This is as it should be. Don't be fooled by the schedules that show only UDC. That's bogus, and you can't really infer much from it. Hell, some of the UDC rates are NEGATIVE per kWh, leading you to think you would make money by using power. It isn't so.


That, and step back a bit and look at the big picture -- how much are you paying for the car itself? In my case, the cost of the lease Completely Dwarfs any imaginable electrical cost. Like, down to noise. Tire cost itself is also significant -- add it up. It's getting to where the cost of electricity is just one of the minor marginal costs of driving, compared to (full coverage) insurance, lease/loan, tires, DMV registration.

When we're talking about $20 to $50/month for "fuel", that's a whole different game than $200 for gas. Solar panels make it even less interesting, since you're somewhat insulated from the actual cost of electricity.

 

[CaryLeaf]

It's easy to see how this car (for now) would cost less to operate than most ice's based on mpg with today's gasoline vs electric prices. When you add in depreciation (included in that is assumed progression with EV technology) and convenience (also part of EV tech) it really muddies the water. Then you talk about regional differences in cost (driven by taxes, temperature, terrain, etc) it gets really hard to calculate accurate estimates..... especially for the future.

 

[lonndoggie]

But you have to know what your'e looking at.

Amen to that. Have to start looking for UDC vs. Total in the descriptions; hadn't been doing that, and I hope they're consistent with it.

FWIW I didn't think the DR-SES had tiers. That's news to me.

They don't--time yes, tiers, no.

If you're looking at this page: http://www.sdge.com/nem/rates.shtml

It shows tiers in the first chart, but that's for the normal domestic rate.

The second chart shows the TOU rates.

And I notice that neither is described as UDC or Total. Dammit.

EDIT: It was easy to miss as an embedded link in my earlier post in this thread, but this document has all the rate info for all three experimental EV TOU rates: http://www.sdge.com/tm2/pdf/2219-E.pdf