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by mcgingras 1048 days ago
Where I'm located I'm billed $.07 per kwh. My model 3 LR has a 75 kw battery, so to charge it from totally empty to totally full would cost $5.25. Tesla's claims are a bit inflated, but I can get 300 miles on a full charge, putting the cost to drive 100 miles at $1.75. Even if we took an extremely generous approximate of 50mpg, it would take 2 gallons for an ICE vehicle to travel 100 miles. Where I'm located, gas is going for $4 a gallon, so it would cost $8.00 to travel the same 100 miles in an ICE vehicle.

If you're charging at home, the EV easily wins.

However, charging away from home can get expensive. During peak hours, it's possible to find charging for $.50 per kwh. Now it would cost $37.50 or $12.50 to drive 100 miles. Compared to the $8.00 in the ICE car, the EV is more expensive.

I think it's a bit disingenuous to claim that most cars cost more to charge than to fill up with gas. If you are able to charge at home, EVs are cheaper to drive per mile.

15 comments

That's roughly around what I'm seeing as well as my electric is about the same rate. I'm in the midwest and gas is a little cheaper where I'm at, but it's still significantly cheaper to charge. Supercharging isn't too bad around me but I rarely ever use it. I did get to experience supercharging in California recently and it was probably as much or more than gas there which is probably why you see articles like this.

No one mentions oil either. I probably pay $100-150 a year to change the oil in my other ICE vehicle.

+ other maintenance costs that EVs don’t have to deal with (brakes, etc.)
EVs may have reduced use of the friction brakes, but I still wouldn't budget 0% to their maintenance ;)
Teslas at least are rated for the lifetime of the car, but it’s fair to say the chance of them getting replaced is higher than zero especially if you drive it a long time and brake aggressively.
don’t tires need to be replaced more often because batteries make the car heavier?
Not sure if that’s an actual known cause, but every personal story I know involves extreme acceleration contributing to quicker tire wear.
> I'm billed $.07 per kwh. My model 3 LR has a 75 kw battery, so to charge it from totally empty to totally full would cost $5.25

You're assuming 100% charge efficiency. I don't know what your actual home charging efficiency might be, but users seem to be reporting in the 80% to 95% range, with more in the 90s than 80s. So your actual cost could be $5.50 to $6.50. I'd guess that charging efficiency goes down as the battery gets older, but I have no evidence for that.

$0.07 per kwh also seems unusually cheap; where I am, costs are closer to $0.15 per kwh. So $11 to $14 per full charge sounds like a more realistic estimate for me, which still beats gas, but not quite as handily.

I pay hourly prices in Chicago, and it's often .03 or .04 $/kwh at off peak times.
The overnight electricity rate in Ontario, Canada can be 2.9 cents/kWh, and the price of gasoline is about $1.50/litre ($5.70/gallon). So it's over 10x as much to drive our gasoline vehicle as it is to drive the electric one. A lot over 10x, in fact, since our gasoline vehicle doesn't get anywhere near 50mpg...
This matches my experience with our two EVs.

One thing to add is that range increases a lot when driving below 45 mph. For city driving we get a lot more range for the same cost.

Switching from a minivan to a Nissan Leaf for around-town driving was a huge cost savings per month.

The study has 75% of the EV charging done at commercial chargers at $0.42/kwh. And it also calculates as part of the cost, 12 hours at $33/hour for your time spent driving to, and waiting for, the commercial chargers.
My lowest cost per kWh in SF Bay Area is $0.34 or 5 times your energy cost. I can switch to a plan where past midnight it’s 0.25 but it will bump a good chunk of the day to over $.50 per kWh

In other words, until I get solar, charging a vehicle at home is not a money saving proposition for me

I live in Europe, it's approx. $0.41 per kWh and diesel fuel is $1.60/liter or approx $6,4/gallon.

If I use your example,

- 75 kw battery to full is $30.75 and it's $10.25 per 100 miles;

- 2 gallons for ICE to travel 100 miles, it would be $12.8 per 100 miles.

So electric car would be a clear winner. If I factor in charging at 80% efficiency, it's $12.3 - only a $0.5 difference.

And the country I live in has the 4th highest energy price in the entire block.

Two points I would also consider

1- the service cost of an ICE car would be higher in a long run compared to the electric one due to higher complexity and more moving parts.

2- electric's car battery will wear down overtime and it will probably run less during winter.

I don't have much data though to elaborate on those points.

Yeah price of electricity now when so few cars charging on the grid. What will the price of electricity be when everyone with a car is charging on the grid in the future?
The US is adding cheap renewable energy to the grid at a much higher rate than the rate of adoption of electric cars.
That's good news. Hopefully it will cover the increase in demand in the future.
$.07 where? That is quite a bit below avg in US. Did you include transmission or only generation?
I'm in Idaho and if you do a ToU plan, that's the the off peak number. [1]

EVs make a TON of sense here.

[1] https://www.idahopower.com/accounts-service/understand-your-...

You are assuming 100% efficiency in charging, probably 85% would be more realistic. Not a deciding factor at .07 kWh, but something you would feel at .50 kWh.
It's not just away from home. Where I live, electricity at home is $0.72/kWh during peak hours.
Why would you charge during peak hours?
I don't. I'm responding to the parent's comment:

> However, charging away from home can get expensive. During peak hours, it's possible to find charging for $.50 per kwh.

Another data point.

In NYC, residential power, including transit, taxes, other fees, is almost $0.35 and gas is $3.30

In california it is ~ $0.28-$0.49/kwh

EDIT: last I checked. wholesale rate is $0.02-$0.04/kwh, sigh.

I'm in SF and paid PGE $0.50938/KWh for peak hours electricity last bill.

Actually, from down thread, CA electricity goes up to $0.58!

https://www.pge.com/en_US/residential/rate-plans/rate-plan-o...

https://news.ycombinator.com/item?id=36978291

Most of us don't live in the state of Washington where the electricity flows like wine*. $0.07/kwh is a good bargain these days. The national average across all of the USA is $0.23/kwh

Financially speaking, charging at home in California is a losing proposition.

* Please forgive me, I couldn't resist the Dumb and Dumber reference :p

Actually 26 states (most) have a billing option which provides cheap overnight rates for EV owners. For me, that means $0.01/kwh.

It seems like business insider's analysis lacks crucial nuance to how things actually work.

In a reality which exists beyond napkin calculations, our 2 EV household, our monthly electricity bill just hit its peak of $185 due to this heatwave. During March/October, it goes down as low as $50.

PG&E is charging between 31c - 45c /kWH in CA depending on time of day, season, etc (https://www.pge.com/pge_global/common/pdfs/rate-plans/how-ra...)

so about $7.75 - $11.25 for that 100-mile fillup.

I try to charge during the day when solar covers the charging need, that comes with its own issues too tho.

I charge at home and it works just fine. I pay $0.25-$0.28/kwh. It puts the cost of a full 75kwh battery at ~$19. That’s still cheaper than paying $4.5-$5/gallon at the gas station.

In fact, even if I charge at the supercharger during peak hours, it costs at most the same as buying gas.

Gas prices for most Americans (pretty much all outside of the west coast) are significantly lower than $4.50 per gallon.

https://fred.stlouisfed.org/series/GASREGCOVW

But it really depends on type of vehicle and type of usage.

Lots of start and stop miles, and electric might come out ahead. For example, family with kids that need to drive to various places.

Lots of short drives, but not a lot of total mileage, gas might still make more sense. For example, retiree or spare car.

Lots of long commutes at highway speeds, gas might still make more sense.

Even in Phoenix during off-peak hours (on-peak is between 4-7PM) it's ~$.11 (without fees, this is the USA after all).

But... I just looked at my last bill. Apparently Mid peak is $.58 / kWh at SoCal Edison.

Even the cheapest time, Super off peak is $0.33333 / kWh which is more than Peak Usage in Phoenix, which ends up being $.29 / kWh.

I didn't know it was that bad.

Don’t live in Washington state, have the same cost of electricity at home. Vote out your elected officials.
You are an anomaly. Your cost of electricity can’t be replicated most anywhere else.
And when everyone has an EV charging on the grid what do think the price of electricity will be then?