Check my math: Electric vs Gas

[omgwtfbyobbq]

Living under SoCal Edison rates with a Tesla has triggered an unfortunate rise in my electric bill (as expected).

I wanted to see how economical my new car is against a fuel efficient ICE or hybrid.
Napkin math:
$4/gal / 40mpg = $0.10 per mile

$0.30/kWh / 3mi/kWh = $0.10 per mile


Now the tier rates in SCE don't start at $0.30/kWh, but they do go up quite quickly into Tier 3-4 if I'm driving more often. My driving habits improve when I'm low on battery but I average 350+Wh/mi (worse in the winter).

One might argue that 40mpg is tough to maintain without a hybrid, but gas looks like it's closer to $3.50 in CA (winter).

Does this mean I'm not really saving any money by driving electric?

That's accurate. Others have correctly pointed out that a hybrid doesn't have the size/acceleration of a MS, and they also don't have the $80k price tag.

If you can use most of your electricity between midnight and 6am (super off-peak), then it might be worthwhile to switch to a TOU rate, but if you use enough on-peak/off-peak you won't see much in the way of savings.

In CA, to really get costs down with an EV, an owner probably needs to get solar PV, with net costs of around $.03-$.10/kWh.

 

[TurboFroggy]

Living under SoCal Edison rates with a Tesla has triggered an unfortunate rise in my electric bill (as expected).

I wanted to see how economical my new car is against a fuel efficient ICE or hybrid.
Napkin math:
$4/gal / 40mpg = $0.10 per mile

$0.30/kWh / 3mi/kWh = $0.10 per mile


Now the tier rates in SCE don't start at $0.30/kWh, but they do go up quite quickly into Tier 3-4 if I'm driving more often. My driving habits improve when I'm low on battery but I average 350+Wh/mi (worse in the winter).

One might argue that 40mpg is tough to maintain without a hybrid, but gas looks like it's closer to $3.50 in CA (winter).

Does this mean I'm not really saving any money by driving electric?

No it just means your on the wrong rate plan. You need to switch to an EV at-night off-peak rate plan and use your charge timer.

https://www.sce.com/wps/portal/home/residential/electric-cars/residential-rates

For example, SCE's TOU-EV-D plan, using your same meter and charging between midnight and 6AM costs $0.09-$0.11/kwh.

Time to call SCE and change your rate plan.

Also you will save even more if you can do things at night that use energy, like run the dishwasher, pool/spa pumps on a timer, oven cleaning, HVAC usage etc.

Power is cheaper to produce at night and lots of excess capacity exists after midnight, this is why you can get basically 66% discount or more for using electricity at night.

 

[N4HHE]

One might argue that 40mpg is tough to maintain without a hybrid, but gas looks like it's closer to $3.50 in CA (winter).

My 7 year average in a 2007 Prius was 50.8 MPG. Thats calculator MPG where (total miles driven) is divided by (total gallons consumed), not Fool Computer displayed MPG. Not the mistake too many make of trying to average MPG using (sum of MPG's) divided by (number of MPG's).

 

[drayers]

That's accurate. Others have correctly pointed out that a hybrid doesn't have the size/acceleration of a MS, and they also don't have the $80k price tag.

If you can use most of your electricity between midnight and 6am (super off-peak), then it might be worthwhile to switch to a TOU rate, but if you use enough on-peak/off-peak you won't see much in the way of savings.

In CA, to really get costs down with an EV, an owner probably needs to get solar PV, with net costs of around $.03-$.10/kWh.

omgwtfbyobbq hit it on the head. I have looked at TOU and having a separate meter for my vehicle. Currently neither are more cost effective with my peak and off-peak use and the cost of the separate meter install.

I looked into getting solar panels, but my unit gets 100A from the street. Apparently I would need a minimum of 200A and digging out the line and replacing it was way too costly

 

[ABVA]

Today used the Chargepoint for first time, just for experience. Cost me $0.75 for one hour and got little over 18 miles back. That is around 4 cents per mile. Even though little bit more expensive and slower than charging at home, but sure beats gas price of roughly 26 cents per mile. Hope this helps.

 

[AmpedRealtor]

Living under SoCal Edison rates with a Tesla has triggered an unfortunate rise in my electric bill (as expected).

I wanted to see how economical my new car is against a fuel efficient ICE or hybrid.
Napkin math:
$4/gal / 40mpg = $0.10 per mile

$0.30/kWh / 3mi/kWh = $0.10 per mile


Now the tier rates in SCE don't start at $0.30/kWh, but they do go up quite quickly into Tier 3-4 if I'm driving more often. My driving habits improve when I'm low on battery but I average 350+Wh/mi (worse in the winter).

One might argue that 40mpg is tough to maintain without a hybrid, but gas looks like it's closer to $3.50 in CA (winter).

Does this mean I'm not really saving any money by driving electric?

Doesn't your electric company offer time of use plans or a dedicated EV charging plan?

Here in AZ I have solar and so I am on a net metering plan combined with a 12pm-7pm (peak) TOU (time of use) plan. My peak rates are 9¢ per kWh and 5.5¢ per kWh off-peak.

 

[SFOTurtle]

Doesn't your electric company offer time of use plans or a dedicated EV charging plan?

Here in AZ I have solar and so I am on a net metering plan combined with a 12pm-7pm (peak) TOU (time of use) plan. My peak rates are 9¢ per kWh and 5.5¢ per kWh off-peak.

I don't live in SoCal, but I looked into this for a friend who lives in LA and just bought a Tesla, and yes, SoCal Edison does offer two rates for EV drivers (as others have posted, the SoCal Edison plans have advantages over PGE's EV-A plan here in the SF Bay Area). One of the TOU rates does NOT require the installation of a separate meter. Unless the OP is working at night and needs to charge during the day, it should still be quite a bit less than $0.30/kWh overall with the MS by choosing the EV rate plan that does not require a separate meter.

Bottom line, I agree with the numerous posts in this thread that say that the OP needs to change his/her rate plan. There is no scenario where anyone needs to pay $.30/kWh on average.

 

[ABVA]

Living under SoCal Edison rates with a Tesla has triggered an unfortunate rise in my electric bill (as expected).

I wanted to see how economical my new car is against a fuel efficient ICE or hybrid.
Napkin math:
$4/gal / 40mpg = $0.10 per mile

$0.30/kWh / 3mi/kWh = $0.10 per mile


Now the tier rates in SCE don't start at $0.30/kWh, but they do go up quite quickly into Tier 3-4 if I'm driving more often. My driving habits improve when I'm low on battery but I average 350+Wh/mi (worse in the winter).

One might argue that 40mpg is tough to maintain without a hybrid, but gas looks like it's closer to $3.50 in CA (winter).

Does this mean I'm not really saving any money by driving electric?

If you are getting 40 miles a gallon, you are probably not comparing the same class of cars. TESLA is a luxury sports sedan. I am not aware of any luxury sports car that gives 40 miles a gallon. Would you please provide make of the car that you used in this comparison?

 

[jerry33]

If you are getting 40 miles a gallon, you are probably not comparing the same class of cars. TESLA is a luxury sports sedan. I am not aware of any luxury sports car that gives 40 miles a gallon. Would you please provide make of the car that you used in this comparison?

Not everyone that purchases a Model S comes from a car of the same type. Some of us come from very economical cars. I have an idea that most folks compare the Model S to their previous car.

 

[ABVA]

Not everyone that purchases a Model S comes from a car of the same type. Some of us come from very economical cars. I have an idea that most folks compare the Model S to their previous car.

All I was suggesting was to have apples to apples comparison. If you compare cost of operating a bicycle to any ICE or EV, bicycle wins.

Model S has a lot more to offer, in terms of safety, fun, range etc. yet is more economical to operate given equal parameters for comparison.

 

[AmpedRealtor]

My P85 replaced my 2007 Prius Touring. Totally not the same class of car, but let's compare them for fun.

Annual Mileage: 20,000
Average Cost of Regular Unleaded: $3.15/gal
Prius Average Mileage: 48 MPG

Annual cost to fuel Prius: $1,312


Average Cost of Electricity: $0.06 per kWh
Annual Model S Electricity Usage: 7,000 kWh (20,000 miles @ 265 mi/85 kWh plus 1,825 miles for vampire loss)

Annual cost to fuel Model S: $420


In my case, the Model S is much more economical to fuel than my Prius. By a factor of 3x.

 

[jerry33]

My P85 replaced my 2007 Prius Touring. Totally not the same class of car, but let's compare them for fun.

Annual Mileage: 20,000
Average Cost of Regular Unleaded: $3.15/gal
Prius Average Mileage: 48 MPG

Annual cost to fuel Prius: $1,312


Average Cost of Electricity: $0.06 per kWh
Annual Model S Electricity Usage: 7,000 kWh (20,000 miles @ 265 mi/85 kWh plus 1,825 miles for vampire loss)

Annual cost to fuel Model S: $420


In my case, the Model S is much more economical to fuel than my Prius. By a factor of 3x.

In the real world it's more like this for a 2004 Prius:

12 months prior to Oct 2004
Gas: $466.13 Miles: 13,333 $/mile: $0.0350
Cost of gas based on 16,000 miles: $559.37


12 months prior to Oct 2005
Gas: $686.77 Miles: 16,631 $/mile: $0.0413
Cost of gas based on 16,000 miles: $660.71


12 months prior to Oct 2006
Gas: $708.38 Miles: 14,716 $/mile: $0.0481
Cost of gas based on 16,000 miles: $770.19


12 months prior to Oct 2007
Gas: $825.08 Miles: 17,963 $/mile: $0.0459
Cost of gas based on 16,000 miles: $734.92


12 months prior to Oct 2008
Gas: $889.01 Miles: 15,855 $/mile: $0.0561
Cost of gas based on 16,000 miles: $897.14


12 months prior to Oct 2009
Gas: $774.33 Miles: 20,641 $/mile: $0.0375
Cost of gas based on 16,000 miles: $600.23


12 months prior to Oct 2010
Gas: $613.65 Miles: 14,589 $/mile: $0.0421
Cost of gas based on 16,000 miles: $673.00


12 months prior to Oct 2011
Gas: $522.04 Miles: 10,606 $/mile: $0.0511
Cost of gas based on 16,000 miles: $817.71


12 months prior to Oct 2012
Gas: $857.03 Miles: 16,024 $/mile: $0.0535
Cost of gas based on 16,000 miles: $855.75


Up to February 26, 2013 fill
Gas: $259.00 Miles: 5,458 $/mile: $0.0475
Cost of gas based on 16,000 miles: $759.25

 

[N4HHE]

2007 Prius

Last 12 months:
$420.11 in fuel, average $3.202/gallon, 50.43 MPG, $0.064/mile.

Last 7 years:
$3442.36 in fuel, average $2.874/gallon, 51.16 MPG, $0.056/mile.

Incremental charge for electrical power is $0.083700/kWh + 4% tax.

 

[brianstorms]

I have been disappointed with how much it costs to charge my Model S.

I'm in San Diego, so I have to use SDG&E. I've only owned the car since August 29, 2013, and the rates have snuck up several times. I have a dedicated meter for the garage (long story, posted elsewhere) and use SDG&E's EV-TOU rates, supposedly, and only charge after midnight to get their "Super Off-Peak Rate".

The Super Off-Peak Rate is now $.12270/kWh. My latest bill shows 320 total kWh used, over past 30 days. (The rate actually snuck up during the billing period; it was $.11486 before the hike).

Then I get to pay another $.04088 per kWh for "Electricity Generation" on top of "Electricity Delivery", so I am really paying $.1635 per kWh --- at the "Super Off-Peak" rate!

Bottom line, it cost me $56.54 to charge my car at home for 30 days. I've really lowered the charge limit too (I have it set around 132), and have attempted to drive less to see if I could get the bill below $50.

I guess I was not expecting having to pay over $50 a month for the car's electricity. Now, I was paying $4000/yr for my ICE beforehand, which works out to $333/mo, so I am saving lots, in theory. Well, that is, after I account for paying $3650 to install the NEMA 14-50 and dedicated SDG&E meter, I guess I will start "saving lots." Sigh. (And no, I can't go solar; it's a condo.)

Update:

Here's SDG&E's listing of current rates. They conveniently have rounded the numbers down, so instead of the actual $.1635 they show $.16 for super-off-peak:

So when I hear the kind of off-peak rates others are getting around North America, I shudder at how expensive SoCal is.

 

[astrotoy]

I don't know how petitioning the California PUC works, but SDGE EV rates are much, much higher for midnight than PGE in northern Cal, which is around 10 cents/kwh.

BTW, in an apples to apples comparison of ICE to EV, my other car is 2007 Lexus LS460L which is the only other 99 rated Consumer's Reports car and does 0-60 in 5.6sec, like the Model S. It also costs about the same . I get about 18 mph using premium, vs. 350w/mi in my Model S. At $4.20/gallon vs 10 cents/kwh,
Lexus $2800/year for 12,000 miles
Tesla S $420/year for 12,000 miles

Does not included now minimal vampire loss for the Telsa nor oil changes for the Lexus.

 

[N4HHE]

So when I hear the kind of off-peak rates others are getting around North America, I shudder at how expensive SoCal is.

December 2013 the flat rate 24 hours/day TVA in Huntsville, AL was $0.09324 for use above 1400 kWh/mo and $0.0851 for the first 1400. Even so I'm not too thrilled at my coming electric bill. Then again I'm driving the MS about twice as much as the Prius previously.

If you do not like your current cost of living then you should consider moving.