Fuel Cost saving is actually 90%?

[H2050]

So I have done some math, and found that my gas cost went from $20 a week to under $2 electricity a week.

So before my M3 I drive a Honda HRV, doing 8.8L/100km, and for gas cost is about 1.50/L if I fuel with the "89" mid tier.
My daily round trip is 20km, but traffic is quite bad so usually I have to pay $18-20 a week in gas.

Now my M3 that I owned for 3 days now, charging at home at $0.065/kwh off-peak, each kwh provides 6-7 km, and daily consumption will be 4kwh = $0.26. I measured there is about 10% inefficiency in charging, so the cost is about $0.3 a day and still under $2 a week.

Compare ICE cost of $20 a week to $2 a week that is a 90% reduction in fuel cost. Wait what? I triple checked my maths and it looks like it is what it is. What do you guys think?

 

[JeffK]

It all depends on electricity rates and gas costs. Me, for example, my trip to work is 50 miles (80.5 km) round trip. I spend $33 in gas each week.

Now electricity for me is $0.10 / kWh so if I were to average around 4 mi (6.4 km) / kWh then that's $1.25 per day or $6.25 per week or an 81% reduction in costs. Also equates to a savings of $107 per month.

Although I should mention, when I had my Prius, my weekly expense for gas was $18 and the price of gas was lower. That would have only been a 65% reduction.

 

[T34ME]

I have Solar City PV on my roof. My gasoline expense has been reduced by 100%.

 

[JeffK]

I have Solar City PV on my roof. My gasoline expense has been reduced by 100%.

...and it's paid off and you have a 100% ROI?

 

[cella]

So I have done some math, and found that my gas cost went from $20 a week to under $2 electricity a week.

So before my M3 I drive a Honda HRV, doing 8.8L/100km, and for gas cost is about 1.50/L if I fuel with the "89" mid tier.
My daily round trip is 20km, but traffic is quite bad so usually I have to pay $18-20 a week in gas.

Now my M3 that I owned for 3 days now, charging at home at $0.065/kwh off-peak, each kwh provides 6-7 km, and daily consumption will be 4kwh = $0.26. I measured there is about 10% inefficiency in charging, so the cost is about $0.3 a day and still under $2 a week.

Looks like your gas and electricity prices are extremely favorable for EV driving. In USD your prices are about $4.40/gallon and 5 cents/kWh. Here in the SF Bay Area, gas is cheaper and electricity much more expensive ($3.60/gallon and 20 cents or more per kWh). I think I should move to Canada.

 

[Dutchie]

I don't save because I drive now more than twice as much and I spend money on these leasurly drives to anywhere/nowhere and drinking coffee or eating something, while I would otherwise stay at home.

 

[T34ME]

...and it's paid off and you have a 100% ROI?

Yep, no electricity bill for home or auto plus rebate for overproduction from local utility. It's California (Ecotopia)! Outside temp high was 99F today and never turned on a.c. California has mandated for years that all new construction have high rated wall and roof insulation. More and more construction is including solar panels as standard. More reasons why real estate is so expensive here.

 

[nvx1977]

Here in New England, I pay about 18 cents per kWh for electricity, which is higher than the US average. My utility thus far has not offered time-of-use plans, so have no way to take advantage of peak vs non-peak hours. Still, things look pretty good, and better than a few months ago with gas prices going up.

Using $2.75/gal pricing at the pump and an 18gal tank for my old Sonata, that's about $50. Based on my actual use mpg, I get 500 miles on a full tank. So I pay about 10 cents per mile with the Sonata.

With Model 3, taking into account efficiency reported by the car and adding 15% charging loss, the cost is just under 4 cents per mile under my utility's cost for Model 3. In reality the calculation is more complicated, as most of the electricity comes from solar. But figured I'd share the non-solar costs.

TBH, even if the costs were break-even with my old Sonata, my primary concern all along was CO2 emissions, and when you do the comparison there, the Model 3 slaughters the Sonata. It helps though that in my region, there is very little reliance on coal, and the growth of renewables is way above national average.

Here's a good visualization of how EVs stack up to ICE in various parts of the country:
New Data Show Electric Vehicles Continue to Get Cleaner

 

[ACPark]

...charging at home at $0.065/kwh off-peak ... what do you guys think?

I'd ask if you've added in delivery, regulatory, and tax to your off-peak rate. If not you'd need to add those costs to the electricity which would about double the effective rate for electricity I suspect, or subtract the same fees from the gas which would significantly lower its cost.

I imagine it would still be between 20% and 25% the cost per km for electricity over gas.

 

[brobinson]

So I have done some math, and found that my gas cost went from $20 a week to under $2 electricity a week.

So before my M3 I drive a Honda HRV, doing 8.8L/100km, and for gas cost is about 1.50/L if I fuel with the "89" mid tier.
My daily round trip is 20km, but traffic is quite bad so usually I have to pay $18-20 a week in gas.

Now my M3 that I owned for 3 days now, charging at home at $0.065/kwh off-peak, each kwh provides 6-7 km, and daily consumption will be 4kwh = $0.26. I measured there is about 10% inefficiency in charging, so the cost is about $0.3 a day and still under $2 a week.

Compare ICE cost of $20 a week to $2 a week that is a 90% reduction in fuel cost. Wait what? I triple checked my maths and it looks like it is what it is. What do you guys think?

That 6.5c/kWh likely does not include the additional fees for delivery and other stuff. Here in Ohio, the quoted cost per kWh is 5.5c, but it actually works out to around 12c when you factor in all of the associated fees. It will still be a huge savings for you.

 

[Phrixotrichus]

I´m incredibly jealous of the low per kwh prices people are posting here.
We´re sitting at ~25+ € cts per kwh here in germany with no off peak tariffs or anything else.

If I´d buy a Model 3 now my fuel savings compared to my current lpg modified v6 would be near zero thanks to that.....

 

[GoneCrazy]

I don't save because I drive now more than twice as much and I spend money on these leasurly drives to anywhere/nowhere and drinking coffee or eating something, while I would otherwise stay at home.

You're just now spending that money on life enrichment as opposed to fuel.

 

[SageBrush]

What do you guys think?

I think you make this exercise too difficult.

6.5 cents / 6.5 km = 1 cent per Km by EV
150 cents /11.36 km = 13 cents per Km by petrol

 

[No2DinosaurFuel]

you guys and your cheap electricity. Here in CA, we get $0.23 for electricity. Still cheaper than petrol, but no where near the 90%.

 

[chronopc]

I used to get gas from Costco which would take 30 minutes on average. The time savings for me is over 90%.

 

[JonathanD]

I used to get gas from Costco which would take 30 minutes on average. The time savings for me is over 90%.

I feel so badly for those people when I drive by. To add insult to injury they have to sit their idling, burning gas, waiting to fill their tank with gas.

 

[Cheburashka]

So I have done some math, and found that my gas cost went from $20 a week to under $2 electricity a week.

So before my M3 I drive a Honda HRV, doing 8.8L/100km, and for gas cost is about 1.50/L if I fuel with the "89" mid tier.
My daily round trip is 20km, but traffic is quite bad so usually I have to pay $18-20 a week in gas.

Now my M3 that I owned for 3 days now, charging at home at $0.065/kwh off-peak, each kwh provides 6-7 km, and daily consumption will be 4kwh = $0.26. I measured there is about 10% inefficiency in charging, so the cost is about $0.3 a day and still under $2 a week.

Compare ICE cost of $20 a week to $2 a week that is a 90% reduction in fuel cost. Wait what? I triple checked my maths and it looks like it is what it is. What do you guys think?

I think you are way off.

There is no way a kwh in Onterrible is 0.065/kwh.

I think the transmission fee alone is like 0.11, and there is some debt free of 0.07, plus 13% HST on top.

 

[sub]

I have 8kw solar system with a tiered rate, installed system 7 years ago and the system has already paid for itself. With the tiered rate I sell power back at 2-4x the off peak rate at night used for charging depending on time of year and peak/partial peak rates. Add free supercharging on our X and our fuel is free. I've also cut down miles on our other gas vehicle by 30-50%. Solar is the way to go with EV.

 

[ksumnole]

Edit, this post pertains to Ontario, Canada data:

Although the stated rate for off-peak is $0.065, you have to factor in regulatory and loss-adjustments as well as taxes. You can use the OEB bill calculator to figure it out for yourself, but for me, off-peak ends up being about $0.095 per kwH.

Bill calculator | Ontario Energy Board

The way to do it, is to put in zero consumption and see what your bill would be.

Your Electricity Charges
Electricity
Off-Peak @ 6.5 ¢/kWh 0.00
Mid-Peak @ 9.4 ¢/kWh 0.00
On-Peak @ 13.2 ¢/kWh 0.00
Delivery 21.00
Regulatory Charges 0.25
Total Electricity Charges $21.25
HST 2.76
8% Provincial Rebate* (-$1.70)
Total Amount $22.31

Next, put in some usage and re-calculate, here I used 75kwH:

Your Electricity Charges
Electricity
Off-Peak @ 6.5 ¢/kWh 4.88
Mid-Peak @ 9.4 ¢/kWh 0.00
On-Peak @ 13.2 ¢/kWh 0.00
Delivery 22.59
Regulatory Charges 0.56
Total Electricity Charges $28.02
HST 3.64
8% Provincial Rebate* (-$2.24)
Total Amount $29.43

So the difference is $7.12

So basically it would cost be $7.12 to fill up the Model 3. Perhaps there is some in-efficiencies when charging, but it should be negligible.

You could then take your range (currently I think I would get about 475 kms at full charge) and convert that to to a price per 100 kms.
For me I get $1.499 per 100/kms. If I converted to the price of gas of we are at about 1.15 L/100 kms

You could take your Wh/km to do different calculations, but you are really splitting hairs.

So my calculations show me that going from my 12L/100km SUV to this car is about 90.5% cheaper.

Long story short.....I agree with the OP

 

[SW2Fiddler]

I haven't added Solar yet.
I am in the Texas grid ("ERCOT"), however, and can choose among many electricity vendors and plans. I was able to switch to "TXU Free Nights" plan and have observed over a few billing cycles.

This plan re-calculates any kWh during night (8 PM to 6 AM is what I selected), sets rate to $0.00, which removes any Calculated Tax for that power, PLUS forgives the transmission surcharge of ~3 cents.

I thought it too good to be true, but since I schedule charging for 8:02 PM, I have a 100% fuel savings situation going on.

I think I need to get a PowerWall at this point. There's a whole lot of Cheap (often free) West Texas Wind Power on the grid.