Is an electric car still cheaper to drive with gasoline at $2/gallon?

[abasile]

I would be very curious to see your reference for this, as charging losses are variable depending on the items I noted above.

The general consensus is that the EPA is indeed basing MPGe on "wall to wheel" energy usage, in controlled conditions. This is what I recall reading in multiple places. Spending a few minutes on this, I'm not finding much corroboration in official documents, but the numbers do add up as discussed above.

Here's an older TM forum thread that addresses this:
Model S EPA rating 89 MPGe | Forums | Tesla Motors

Take it with a grain of salt, but this Wikipedia entry can be a good starting point, and it does state that "wall to wheels" numbers are used:
Miles per gallon gasoline equivalent - Wikipedia, the free encyclopedia

Also, one big negative for gasoline vehicles in the cold is the need to run the engine "rich" for a longer period of time. Not only does this use more fuel, it produces more fumes. Cleaning snow off of a warming-up EV is so much nicer for this reason.

 

[ToddRLockwood]

Don't forget to add in the vampire load to the calculations. If you drive the car on a longer trip, it gets much better electron economy than short trips here and there(just like any other car). Charging the car on a 14-50 @40A, at $0.10 per kWh electricity cost, it costs right at $1 to get 30 rated miles. With the vamipre load in the winter, sometimes I can only go 15 real miles on 30 rated. That is only equivalent to a 30mpg vehicle with gasoline at $2 per gallon.

In cold temps some energy is used to heat the battery. That's what you're experiencing when you get 15 real miles out of 30 rated, not vampire loss. As you drive and the battery warms up, that range should improve dramatically. It's hard to tell whether the EPA would have included battery heating in their 89MPGe calculation. Their testing could have been done at room temperature on a dynamometer.

What is really needed here is data measured at someone's electric panel over the course of a year in a region that includes winter conditions. Does anyone out there have this data for a Model S P85?

 

[qwk]

In cold temps some energy is used to heat the battery. That's what you're experiencing when you get 15 real miles out of 30 rated, not vampire loss. As you drive and the battery warms up, that range should improve dramatically. It's hard to tell whether the EPA would have included battery heating in their 89MPGe calculation. Their testing could have been done at room temperature on a dynamometer.

What is really needed here is data measured at someone's electric panel over the course of a year in a region that includes winter conditions. Does anyone out there have this data for a Model S P85?

FW 6.0 does not have the battery heater come on unless it's well below 0F. It doesn't matter though, because I use range mode in the winter. Range mode has always deferred the battery heater for as long as possible.

 

[Doug_G]

FW 6.0 does not have the battery heater come on unless it's well below 0F. It doesn't matter though, because I use range mode in the winter. Range mode has always deferred the battery heater for as long as possible.

The battery heater comes on above 0 degrees C.

 

[qwk]

The battery heater comes on above 0 degrees C.

It doesn't on my car.

 

[Doug_G]

It doesn't on my car.

If you car is totally cold soaked at 0 degrees C, does it show regen limit?

 

[Brass Guy]

Our temps have been mostly in the 20's and low 30's. (F) It is quite obvious from the orange bar that below 15kW regen limit, my battery heater comes on with range mode off. I think it tapers down as it warms, I'm not sure.

I thought EPA ranges were listed with accessories such as AC off. I expect that would extend to EVs being rated without heaters on, in a comfortable ambient temperature.

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Oh ya, on topic: There are a lot of factors to consider. Each person's case is different.
My previous car got just about 30mpg and I'd still be driving it now. Gasoline is right around the $2.00 mark and electricity is over .23/kWh (I'm changing suppliers, so should go down to about .19).
So for me, it would be cheaper to drive my gas car. But I agree with David99 above, saving fuel money was not the primary reason for getting a MS. And I think we all can agree that oil products will not remain at these low prices forever, and I admit my electric prices may come down in a few months.

For most, driving an EV still costs much less than their ICE; but not for everyone.

 

[qwk]

If you car is totally cold soaked at 0 degrees C, does it show regen limit?

Yes, but the regen limit has nothing to do with the battery heater coming on. I drive the car to the office with the regen disabled, and get there with the regen disabled. When the pack heater came on with FW5.8, the car had 40kw of regen available by the time I got to the office. If I charge the car at the office, if the regen limit is 30kw after the charge, the car still has only about a 35kwh regen limit after I get home. There is very little difference in rated miles used(15-17). Obviously the pack heater isn't coming on.

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BTW this is at temps close to 0F. 0C is swimming weather here.

 

[Doug_G]

BTW this is at temps close to 0F. 0C is swimming weather here.

Same here. It's a nice balmy -15C (5F) here right now.

The pack heater power is adjustable from 0 to 6 kW (actually my best estimate is 5.5 kW max). The power draw may not be that obvious when its at low power.

From what I've seen, pack heat is applied at some level until it reaches about 30 kW regen limit. You need to drive it to get to the full 60 kW regen (if it's even possible).

Of course Range Mode will limit the heater power used.

 

[qwk]

Same here. It's a nice balmy -15C (5F) here right now.

The pack heater power is adjustable from 0 to 6 kW (actually my best estimate is 5.5 kW max). The power draw may not be that obvious when its at low power.

From what I've seen, pack heat is applied at some level until it reaches about 30 kW regen limit. You need to drive it to get to the full 60 kW regen (if it's even possible).

Of course Range Mode will limit the heater power used.

You are right. My main point was that one is not going to save much money in the winter driving the Model S, with gas at $1.50-$2.00. In the summer though, the car gets rated very easily, which at the power rates(and today's gasoline prices) I pay, it's equivalent to a 60mpg car. That said, I would still very much have bought the car if I had to do it again(even if I knew that gasoline was going to be this low again). There is no way in hell that gasoline is going to stay this cheap.

 

[Doug_G]

Sure, but a 60 mpg gas car is a small econo box. This is a very capable full size vehicle, yet is much cheaper to run than my previous (and somewhat smaller) Infiniti G37, even in winter conditions.

(Personally I think I'd prefer something more the size of the sometime-off-in-the-future Model 3; presumably it will get better mileage than the Model S.)

 

[qwk]

Sure, but a 60 mpg gas car is a small econo box. This is a very capable full size vehicle, yet is much cheaper to run than my previous (and somewhat smaller) Infiniti G37, even in winter conditions.

(Personally I think I'd prefer something more the size of the sometime-off-in-the-future Model 3; presumably it will get better mileage than the Model S.)

Yes, there is no ICE car of the size and power that the Model S has that gets anywhere near 60mpg.

 

[dhrivnak]

For me the Roadster is still half the fuel cost of our old Prius at $2 gas. And the Roadster is a LOT more fun to drive.

And i am able to make my own fuel from my rooftop solar. Try that for any gas car.

 

[qwk]

Sure, but a 60 mpg gas car is a small econo box. This is a very capable full size vehicle, yet is much cheaper to run than my previous (and somewhat smaller) Infiniti G37, even in winter conditions.

(Personally I think I'd prefer something more the size of the sometime-off-in-the-future Model 3; presumably it will get better mileage than the Model S.)

Yes, there is no ICE car of the size, and power of the Model S, that gets anywhere near 60mpg.

 

[30seconds]

Yes, there is no ICE car of the size, and power of the Model S, that gets anywhere near 60mpg.

Or takes regular unleaded

 

[Lithium]

Watching the news this morning and I see the gas prices are creeping back up again. This can only help electric cars.

 

[jerry33]

The real problem is that people think when gas prices go down they will stay down forever. In general, gas prices go up and down but typically, the low point isn't as low as the last low point and the high point is higher than the last high. This one is an aberration caused (presumably) by political machinations. In almost two years and almost 40,000 miles it has cost less than $1000 in grid electricity (sadly no solar) to drive my Model S. If you had a car that averaged (and averaged doesn't mean the highway miles rating) 40 mpg you would have purchased 1000 gallons of gas. And the fact that regular gas is $2 today, doesn't change the historical price data over the last two years, which the 40 mpg car would have purchased. (e.g. the oil company doesn't go back and refund what's been paid over $2 per gallon.)

 

[Doug_G]

Interesting that the inflection point happened pretty much simultaneously with the Saudi king passing. I think we can expect an upward trajectory now.