Still worth getting a Model 3 if Electricity costs more than Gas?

[Saghost]

Ahh .. now I am following you. It would be a poor idea to run a series of heat pumps.

People in the SE United states put DHW heat pumps inside the house because they get "free" cooling and dehumidication (a HUGE benefit) during their mostly too hot climate. They pay with noise.

I'm pretty sure Escondido should place the heat pump in the garage.

I've wondered before whether it makes sense to place the heat pump in a place that with vents and some pipes could have intake and outflow vary between inside and outside depending on season. Maybe in a home designed that way. The same could be said for the fridge ... which is also a heat pump. My rather crude calculations for a fridge in my overall winter climate suggested at least a 50% energy savings if it was paired with a heat sink and good insulation. About 0.5 kWh/day consumption for a 22 ft^3 fridge/freezer.

Integrated house thermal management system?

One smart high efficiency heat pump that provides high and low temperature sources for hot water, built in fridge/freezer, and HVAC, taking maximum advantage of ambient temperature and maybe even thermal storage?

Interesting in principle; I'm not sure how viable it'll be in practice. Presumably a lot of pipes to insulate...

 

[SageBrush]

Integrated house thermal management system?

The holy grail !!

 

[Daniel in SD]

Integrated house thermal management system?

One smart high efficiency heat pump that provides high and low temperature sources for hot water, built in fridge/freezer, and HVAC, taking maximum advantage of ambient temperature and maybe even thermal storage?

Interesting in principle; I'm not sure how viable it'll be in practice. Presumably a lot of pipes to insulate...

Add batteries, solar and a 2kW natural gas generator (also with heat recovery) to it!
SDG&E is spending $22k a house to underground the power lines on my street. I was wondering if solar, batteries, and a small generator for consecutive cloudy days (rare in San Diego) would be cheaper

 

[Glamisduner]

I think it will actually be cheaper to charge my model 3 off a large diesel generator, of course the cost of such a generator would be expensive

 

[Saghost]

I think it will actually be cheaper to charge my model 3 off a large diesel generator, of course the cost of such a generator would be expensive

If money is the goal, it's really hard to beat a 1999 Toyota Camry.

If you're buying a fancy electric car that's going to cost a lot of money anyway, why obsess over a few dollars to charge it?

 

[Glamisduner]

If money is the goal, it's really hard to beat a 1999 Toyota Camry.

If you're buying a fancy electric car that's going to cost a lot of money anyway, why obsess over a few dollars to charge it?

It's not really a few dollars but it would be funny just to prove a point.

27 kilowatt-hours (kWh) used per 100 miles is what the M3 is rated for, my daily commute is minimum of 82 miles but sometimes over 100. So lets use 82 82 miles is roughly 22kWh a night to charge assuming no losses which isn't realistic, but lets use that figure.
22kWh at 40 cents per Hwk is about $9 a night. this averages out to $279 a month for power or 3348 a year. Cutting that number is 1/2 would make a huge difference.

Basically the M3 is impressive since I would be getting to work and back off the same power contained in about 2/3 of a gallon of gas. Problem is the power companies don't want us to drive electric cars (I guess?)

A gallon of gas contains 33.7kWh of energy and costs $3.50 33.7kWH from the power company costs $13.48 in winder and over $15 in the summer.

 

[Saghost]

It's not really a few dollars but it would be funny just to prove a point.

27 kilowatt-hours (kWh) used per 100 miles is what the M3 is rated for, my daily commute is minimum of 82 miles but sometimes over 100. So lets use 82 82 miles is roughly 22kWh a night to charge assuming no losses which isn't realistic, but lets use that figure.
22kWh at 40 cents per Hwk is about $9 a night. this averages out to $279 a month for power or 3348 a year. Cutting that number is 1/2 would make a huge difference.

Basically the M3 is impressive since I would be getting to work and back off the same power contained in about 2/3 of a gallon of gas. Problem is the power companies don't want us to drive electric cars (I guess?)

A gallon of gas contains 33.7kWh of energy and costs $3.50 33.7kWH from the power company costs $13.48 in winder and over $15 in the summer.

The 27 kWh/100 miles rating is from the wall (i.e. including the losses.)

Okay, let's run with your model. Comparable new ICE car: 2018 BMW 340i. 25 mpg combined rating. Best case ICE car: 2018 Prius. 52 mpg combined.

San Diego average gas price for last 6 months: ~$3.30 per gallon for regular from gasbuddy. No handy source for Premium - assume ~$3.50?

82 miles at 25 mpg = 3.28 gallons per day, with premium that's $11.48 per day for the comparable gas car.

Best case car, 1.58 gallons and $5.20.

395 mile range on the BMW means a gas stop every week, for at least five minutes. That's over four hours out of your life every year - and that assumes the gas station is exactly on your commute. What do you get paid per hour? (you don't have to answer that - but if you're figuring the math, it's only fair to add this cost in to the ICE car. The EV doesn't take any time from you (assuming you're charging at home, which is implicit in the math you gave.)

588 mile range in the best case car, so every 7 working days and probably only three hours of your time to add back in.

Do you drive roads with HOV lanes in your daily commute? How much of your time can solo HOV access save you? What's that time worth to you?

Incidentally, if your time is less important to you than the dollars, you can easily chop a third or more off of the commute cost on the model 3 by using superchargers at $0.26 per kWh in California instead of the top tier rates you're apparently paying at home.

Also, if you're under SDG&E (best guess from your listed location) they offer special TOU rates to EV owners:

Electric Vehicle Plans | San Diego Gas & Electric

 

[SpiceWare]

San Diego average gas price for last 6 months: ~$3.30 per gallon for regular from gasbuddy. No handy source for Premium - assume ~$3.50?

My S2000 requires Premium, haven't seen $0.10 between grades for quite some time. Around here it's about $0.30 so:

• $2.35 Regular
• $2.65 Midgrade
• $2.95 Premium

 

[daniel]

It's not really a few dollars but it would be funny just to prove a point.

27 kilowatt-hours (kWh) used per 100 miles is what the M3 is rated for, my daily commute is minimum of 82 miles but sometimes over 100. So lets use 82 82 miles is roughly 22kWh a night to charge assuming no losses which isn't realistic, but lets use that figure.
22kWh at 40 cents per Hwk is about $9 a night. this averages out to $279 a month for power or 3348 a year. Cutting that number is 1/2 would make a huge difference.

Basically the M3 is impressive since I would be getting to work and back off the same power contained in about 2/3 of a gallon of gas. Problem is the power companies don't want us to drive electric cars (I guess?)

A gallon of gas contains 33.7kWh of energy and costs $3.50 33.7kWH from the power company costs $13.48 in winder and over $15 in the summer.

You pay 40¢/kWh??? I thought Maui's 37¢/kWh was the highest in the U.S. I ran a trip calculation on Tesla's web site for fun: Spokane to Sedona. It said I'd pay 27¢/kWh at the superchargers. That's after starting out with a full charge at home at 6¢ or 7¢ per kWh where I live.

I think I once figured that on Maui, a Prius would cost less than a Tesla for "fuel," but a Tesla would cost less than an otherwise-similar car. (The Model 3 is a MUCH nicer car than the Prius, except for the lack of a key fob.)

Clearly, the economics depends a lot on where you are.

But as Saghost pointed out, if money is an issue, a used economy stinker will always be cheaper than any new car. Nobody buys a new car to "save" money. Fuel and service are just numbers that go into the total cost of ownership.

 

[Glamisduner]

The 27 kWh/100 miles rating is from the wall (i.e. including the losses.)

Okay, let's run with your model. Comparable new ICE car: 2018 BMW 340i. 25 mpg combined rating. Best case ICE car: 2018 Prius. 52 mpg combined.

San Diego average gas price for last 6 months: ~$3.30 per gallon for regular from gasbuddy. No handy source for Premium - assume ~$3.50?

82 miles at 25 mpg = 3.28 gallons per day, with premium that's $11.48 per day for the comparable gas car.

Best case car, 1.58 gallons and $5.20.

395 mile range on the BMW means a gas stop every week, for at least five minutes. That's over four hours out of your life every year - and that assumes the gas station is exactly on your commute. What do you get paid per hour? (you don't have to answer that - but if you're figuring the math, it's only fair to add this cost in to the ICE car. The EV doesn't take any time from you (assuming you're charging at home, which is implicit in the math you gave.)

588 mile range in the best case car, so every 7 working days and probably only three hours of your time to add back in.

Do you drive roads with HOV lanes in your daily commute? How much of your time can solo HOV access save you? What's that time worth to you?

Incidentally, if your time is less important to you than the dollars, you can easily chop a third or more off of the commute cost on the model 3 by using superchargers at $0.26 per kWh in California instead of the top tier rates you're apparently paying at home.

Also, if you're under SDG&E (best guess from your listed location) they offer special TOU rates to EV owners:

Electric Vehicle Plans | San Diego Gas & Electric

Yea, I just bought a used volt to give the EV thing a try. Because my truck was costing around $600 a month in gas and my focus was repurchased by ford. It's interesting on the volt I got 80+ mpg on the way to work and I have been averaging around 65 mpg total (but also drving over 100 miles on those two average) however it's not really as big of a savings as you would think since it costs $4 or so to charge at night, $4 for 40-45 miles, very similar to the cost of gas on a pretty typical commuter car (focus was about 32-34mpg average).

Yea I'll have to switch to EV plan once I get the model 3, however I'm not sure how much that actually saves me because peak hours are so expensive under that plan... Actually SDGE calculates for me that plan. Last time I checked it was around $600 more per year (before getting an EV). So it will take a while to make the cheaper charging rate worth while, but it will be worth while with a model 3 (maybe for the volt too, but I haven't switched yet).

You pay 40¢/kWh??? I thought Maui's 37¢/kWh was the highest in the U.S. I ran a trip calculation on Tesla's web site for fun: Spokane to Sedona. It said I'd pay 27¢/kWh at the superchargers. That's after starting out with a full charge at home at 6¢ or 7¢ per kWh where I live.

I think I once figured that on Maui, a Prius would cost less than a Tesla for "fuel," but a Tesla would cost less than an otherwise-similar car. (The Model 3 is a MUCH nicer car than the Prius, except for the lack of a key fob.)

Clearly, the economics depends a lot on where you are.

But as Saghost pointed out, if money is an issue, a used economy stinker will always be cheaper than any new car. Nobody buys a new car to "save" money. Fuel and service are just numbers that go into the total cost of ownership.

yep, just part of the cost of ownership, but certainly a big thing to consider. 40 cents is our winter middle tier and 47 cents in the summer. Our base rates may still be lower than yours. But soon we will have the highest in the nation because prices are going up again soon!
https://www.sdge.com/sites/default/files/regulatory/1-1-18 Schedule DR Total Rates Table.pdf

Tier 3 is what I was hitting before our solar install. Now I usually tip into tier 2 occasionally, but it's a sure thing once I go with an EV.

 

[Zaxxon]

Not targeting anyone here who may be an extreme edge case. This is a great analysis of this topic in the general and state-by-state sense:

 

[Glamisduner]

Not targeting anyone here who may be an extreme edge case. This is a great analysis of this topic in the general and state-by-state sense:

haha I have to disagree, supercharger is cheaper than at home for me. Are you saying living in san diego is an extreme edge case? Maybe. I just went for a walk at work and there was serval model s and a model 3 (me drooling) in the parking lot. So somehow they make sense for some people here. I guess the model 3 isn't well suited for me and my all electric house but I still want to get one

 

[Zaxxon]

Are you saying living in san diego is an extreme edge case?

No, I'm saying your specific specified rate is an extreme edge case. For example, the average residential electricity rate in San Diego is 16.35 cents/kWh.

 

[Glamisduner]

No, I'm saying your specific specified rate is an extreme edge case. For example, the average residential electricity rate in San Diego is 16.35 cents/kWh.

No it's actually not. Not sure how they are getting those numbers:
Total Electric Rates | San Diego Gas & Electric

It might be that they are averaging the rates of the 50 story condos and apartments in downtown San Diego or something. But going directly to the source you can see those numbers are not correct.

 

[Daniel in SD]

No it's actually not. Not sure how they are getting those numbers:
Total Electric Rates | San Diego Gas & Electric

It might be that they are averaging the rates of the 50 story condos and apartments in downtown San Diego or something. But going directly to the source you can see those numbers are not correct.

Yeah no idea where they are getting 16.35c. That might be the rate for commercial without demand charges. I wouldn't be surprised if San Diego had the highest residential rates in the country. It is an extreme outlier. Hawaii is cheaper!

 

[JP Bark]

It's not really a few dollars but it would be funny just to prove a point.

27 kilowatt-hours (kWh) used per 100 miles is what the M3 is rated for, my daily commute is minimum of 82 miles but sometimes over 100. So lets use 82 82 miles is roughly 22kWh a night to charge assuming no losses which isn't realistic, but lets use that figure.
22kWh at 40 cents per Hwk is about $9 a night. this averages out to $279 a month for power or 3348 a year. Cutting that number is 1/2 would make a huge difference.

Basically the M3 is impressive since I would be getting to work and back off the same power contained in about 2/3 of a gallon of gas. Problem is the power companies don't want us to drive electric cars (I guess?)

A gallon of gas contains 33.7kWh of energy and costs $3.50 33.7kWH from the power company costs $13.48 in winder and over $15 in the summer.

With the Electric Vehicle Time-of-Use Plans

On peak is from .24 to .54 Off Peak is from .22 to .28
Electric Vehicle Plans | San Diego Gas & Electric

So charging off peak is anywhere from $5.28 to $6.16
On peak is either $5.28 or $11.88 in the summer.

 

[Asymmetry]

Any possible theoretical gain is quickly wiped out by your first dent or scrape...

 

[JP Bark]

I will take my lucky .083 cents to .1168 cents for power in AZ.

 

[Zaxxon]

No it's actually not. Not sure how they are getting those numbers:
Total Electric Rates | San Diego Gas & Electric

It's funny, as OpenEI has the same average residential rate for SD.

U.S. Utility Rate Database

Anyway, you're clearly right that 16 cents is incorrect for your specific rate plans. But the overnight TOU rate is 23c/kWh which is not going to be enough to make the 3 comparable to a mid-30MPG ICE car, much less worse (see my video link above for the calcs by Ben Sullins). So long as your solar covers your peak usage so you're not getting hosed in that regard.

 

[Glamisduner]

It's funny, as OpenEI has the same average residential rate for SD.

U.S. Utility Rate Database

Anyway, you're clearly right that 16 cents is incorrect for your specific rate plans. But the overnight TOU rate is 23c/kWh which is not going to be enough to make the 3 comparable to a mid-30MPG ICE car, much less worse (see my video link above for the calcs by Ben Sullins). So long as your solar covers your peak usage so you're not getting hosed in that regard.

Unfortunately solar works different under the EV plan. It will not cover my peak usage for the hours 4-9pm for peak. This is why the grandfathered tiered plan is so much better (if you don't have an EV) with the grandfathered plan you put in "x" amount of kW and get credit for "x" amount of kW. If I switch to the EV plan I will get a credit for power at the rate @ for which time period the power generated. So energy produced on non peak is only worth 12 cents per kW. Since peak hours is 4-9:00 I won't be producing much power off solar during that time. Notice how much the price jumps for those peak hours? That is how they get you! You send them power all day for 12 cents per kW until 4:00 then you buy power back from SDG&E at 5 times the cost (yep 60 cents!). So for every 6 hours of power you send them, they will give you back a credit for one hour. It really pisses me off to be honest which is why I'm hesitant to switch plans, but I would be pretty much forced to switch if I buy a model 3.

I suppose a powerwall would be another option, but then I'm looking at significant expenses to have an EV (Maybe something like $15,000 extra?)