Efficiency (Cost per mile)

[drg1012]

I track every drive - miles and kwh used. I also track hourly electric usage by my charger, including preconditioning and my energy cost (I don't include my grid access fee - I would pay that even without an EV). My electricity costs around $0.104/kwh. I also look at what I would have used in gas based on my normal ave mpg of my other car (2021 4Runner) and roughly ave cost of gasoline each day in my area. I live in Colorado - you can clearly see the effect of temperature on cost.

	daily cost	cents/mile	days	miles/day	Gas Cost Savings
	Total	4.4 c​	180​	87.5​	$ 1,820.49
22-Nov​	4.85​	4.4 c​	6​	111.5​	$ 65.16
22-Dec	$ 4.08	4.4 c​	31​	93.2​	$ 254.23
Jan-23​	$ 4.10	4.9 c​	31​	83.4​	$ 270.43
Feb-23​	$ 3.54	4.8 c​	28​	73.3​	$ 287.62
Mar-23​	$ 4.49	4.3 c​	31​	103.6​	$ 434.35
Apr-23​	$ 3.19	4.1 c​	30​	78.7​	$ 283.22
May-23​	$ 3.29	3.8 c​	23​	85.8​	$ 225.48

Sponsored

 

[Nygman]

@drg1012 That's what I'm talking about, your car isn't grabber blue by chance? Glad it isn't just me, although I must admit my wife does make fun of me for doing it, especially when I get really excited after a very efficient trip.

I think it's really interesting how cost per mile fluctuates. I think I'm going to need to improve my spreadsheet game, it looks like I'm not tracking nearly enough.

 

[timbop]

Absolutely I take fuel cost into account; once I got my Mach-E in Feb '21 the only miles my wife's car gets are her driving to work and running errands afterward.

Due to the great incentives on solar in NJ, I am actually paying about 3 cents per mile. I just topped 23,000 miles on my Mach-E for a cost of around $700. At 15mpg my wife's old Durango (she got a PHEV last year) would have needed 1533 gallons to go that distance, and assuming a charitable $3 per gallon average over that time it still would have cost $4600 plus 5 oil changes.

 

[drg1012]

@drg1012 That's what I'm talking about, your car isn't grabber blue by chance? Glad it isn't just me, although I must admit my wife does make fun of me for doing it, especially when I get really excited after a very efficient trip.

I think it's really interesting how cost per mile fluctuates. I think I'm going to need to improve my spreadsheet game, it looks like I'm not tracking nearly enough.

Iced blue silver metallic and my wife makes fun of me about a great many things, this included ;-). Just for giggles, here is daily efficiency vs. daily average temperature:

as well as efficiency vs temperature (blue) and corrected efficiency (grey) (including the effect of reduced storage of the battery at colder temperatures). I have to updates these now that it is starting to warm up....

 

[Nygman]

Would love to do solar but doesn't work for me due to my slate roof and plentiful shade from large old trees I can't cut down. Powering my car with the sun would be my ideal. Instead I am doing research on Community Solar projects via the NYSERDA (https://www.nyserda.ny.gov/All-Prog...Your-Home/Community-Solar/Community-Solar-Map) to see if I can get some benefit.

 

[MikeC]

I did about a hundred miles of driving on Sunday and my MachE GTPE (96 to be exact). It was a mix of highways, nice back roads, with some traffic and city driving mixed in. Based on my charger, I put back in 44Kw and here in New York, I pay $.17 per Kw off-peak delivered. Therefore Sunday driving cost me about $7.48 in energy to recharge. I also just so happen to fill up my other car on Sunday, the price for premium unleaded was $4.53 a gallon. It's an inefficient SUV [Ford Flex EcoBoost], that gets about 14 mi to the gallon on average, based on the type of driving my wife and I do. On this fiil it was 13.8, but I'll go with 14. I calculated it would have taken about four and a half gallons or approximately $31 of fuel the cover my Sunday drive If I took the SUV.

If you look at my mi/Kwh you'll see it wasn't a fuel economy run. It was in the mid-2's. I had a fun drive. I know these efficiency numbers don't look great, but from a cost per mile perspective, I'm spending about 7.7 cents a mile in my MME over .32 cents a mile in my SUV. Even if I were to double the fuel economy of my SUV, that would have the cost, to around $.16 a mile still double what it cost to run my MME. I'm driving the MME is way more fun.

I'm curious if anybody else looks at their efficiency this way. I do it quite often, and I'm still amazed by how much less per mile it cost to run. In averages to about a quarter of the cost every time. Sometimes I've seen it a tad bit better, and on a few occasions worse, but I've never seen it more than half the cost.

While my numbers are for the GTPE, I was wondering if anyone can share their real life calculations for other models, in other states, based on the actual cost of electricity. If you have solar and it's free for you, I'm jealous. I'm not really looking to compare that, I just am curious as to the cost per mile in various regions for various models.

Sorry but a Brit responding. I am so envious of your fuel and Rapid charge prices. For a 500 mile journey (it can be achieved in the U.K ), I want to turn up at a Rapid charger where there are at least 6 (so I don’t have to wait) and I pay £0.79 ($0.98) per KWh, and I get approx 2.8 miles/KWh on a long motorway journey. Fuel is approx £1.55/litre (back street garage) so to travel the same distance in my previous car (BMW 520D tourer (estate)) which with motorway/highway driving averaged 45mpg. Diesel at the moment is £1.55/litre (US gallon is 3.785 litres…..$7.2855), it costs me about £30 more to drive the same distance in my lovely Mach-e. I think I’ll move . Our wonderful government charge 20% VAT for public charging….such an incentive to encourage people to buy electric. Enjoy your wonderful prices….

 

[carbonizedbrett]

I didn't get my JuiceBox until May of last year. I used the reporting to determine total kWh delivered to the car (not what the car reports as "added") and the monthly Ford emails that include my odometer readings to create the table below. There's probably some occasional not-at-home charging throwing my mi/kWh off in some months. I used a round 18 cents/kWh because tracking the all-in rate for PSEG in NJ is just ridiculous. Supply + Delivery is about 20 cents and I get about 2 cent rebate on the next bill for the previous billing period's off-peak usage. (I think people in NJ sometimes forget to include the delivery charge and just look a the "Price to Compare" which just equates the supply charge.)

I have done some "per tank" calculations as well - "filling" the tank to 90% and dividing the kWh delivered by the JuiceBox by the miles since the last "fill-up." Those have been closer to 2 than 3. I was surprised by how much - the car's numbers are usually closer 3 to than 2. I hadn't realized how many electrons were leaking during the fill-up process!

Note: car is kept in attached garage but it gets chilly and I had it set to warm cabin and pre-condition M-F.

 

[timbop]

Sorry but a Brit responding. I am so envious of your fuel and Rapid charge prices. For a 500 mile journey (it can be achieved in the U.K ), I want to turn up at a Rapid charger where there are at least 6 (so I don’t have to wait) and I pay £0.79 ($0.98) per KWh, and I get approx 2.8 miles/KWh on a long motorway journey. Fuel is approx £1.55/litre (back street garage) so to travel the same distance in my previous car (BMW 520D tourer (estate)) which with motorway/highway driving averaged 45mpg. Diesel at the moment is £1.55/litre (US gallon is 3.785 litres…..$7.2855), it costs me about £30 more to drive the same distance in my lovely Mach-e. I think I’ll move . Our wonderful government charge 20% VAT for public charging….such an incentive to encourage people to buy electric. Enjoy your wonderful prices….

The prices he and I mentioned are for charging at home. Rates for DC fast charging at public chargers is usually in the $.40 to $.70 per kwh, so not too far off from your public rates

 

[RickMachE]

The problem with trying to get "exact" is that you can't. Ballpark at best. The efficiency of the charge when the battery is at 50 is different from 70 is different from 90. The drive with the air temp at those different temps, and whether there's a wind, ...

I always tracked my ICE efficiency by recording the readouts with the gas receipt, i.e. miles driven, mpg vehicle shows, mpg calculated, ... But with the EVs, I have better things to do than track each and every errand I run, etc. I track trips, and I use the Trip 1 odometer to track miles between trips and record that before resetting it (Trip 2 is from day of pickup).

The other day I realized I could pull my JuiceBox data into a spreadsheet, and look at reallocating my electric bill to house and auto, not just house. Let's me get a truer read of the actual electric usage in charging, and everything else. Since I know the exact kWh used, and it's always off-peak, I can take the off-peak total, calculate overall proportion of bill, then use that to allocate all the non-specific costs and taxes, then add in the off-peak cost. This allowed me to see my fully loaded cost per kWh ranges by month, as the utility slowly raises rates (they want to raise them faster). Started at 14.3 cents in July 2021, now at 16.8 cents.

I then figured I would add in my total cost to charge publicly (stored in Quicken), then add it all up and say "this is my cost to drive an EV". Sure, that works. But, it's not a per mile number, because it excludes the free charges - hotels, malfunctioning EA chargers, free public chargers, charging at friends and relatives, etc. Not huge, but there none the less. And, I have to wait for the current utility bill to add in those costs since the odometer on the vehicles wasn't recorded at the last bill.

 

[JSeis]

Our Flex twin turbo get 24 mpg on my commute so yours is rather inefficiently used. Our power is dirt cheap at $.0634/KWh. But on long DCFC trips at say $.43/KWh it’s nearly a wash. I pick the Flex due to range and comfort for long (300-400 mile + trips).

Given that I pay about 6X-7X more for electricity on long trips..gas works out.

 

[Nygman]

Our Flex twin turbo get 24 mpg on my commute so yours is rather inefficiently used. Our power is dirt cheap at $.0634/KWh. But on long DCFC trips at say $.43/KWh it’s nearly a wash. I pick the Flex due to range and comfort for long (300-400 mile + trips.

Given that I pay about 6X-7X more for electricity on long trips..gas works out.

I get between 24 and 28 only on highway driving and we want maintaining close to legal speeds. Most of my driving in the flex Is city driving point to point stop and go. 20 minute commutes averaging 15 to 20 miles an hour. 24 would be a luxury. Currently my flex reflects 12.9 MPG on this fill. I'm just comparing like for like in my case. I've also never DC fast charged, my electric is from ConEd.

 

[JSeis]

Of course, the Flex EB is a really good ICE people mover-hauler of serious ass. Imagine if we had the Mach E GT power train!

Sponsored