Cost per mile and justification (spreadsheet??)

[Deanwvu]

Hello,

Now that my purchase-o-rama is nearly complete, I get to move on to the fun side of this whole project: building my ebike and riding it!

I need to (for me, and my wife) justify the cost of this project. There is no doubt ebikes are supremely cost efficient compared to ICE cars, but only if I use it enough!! I can throw together a simple enough spreadsheet to calculate this, but I figure that may have already been done here at ES.

I'd like to log my miles on a spreadsheet that would show my cost-per-mile for operating my bike. This would take into account the initial cost of the bicycle itself, the motor, the electronics, and the battery, and also the cost-per-mile of my electricity. I'd then compare this to the average cost in the USA of owning an ICE vehicle, which is 50-60 cents per mile, best I can find.

I'd want to make this a game of sorts--to keep riding as much as possible to bring my cost-per-mile number down and down and down and eventually well below that 50-60 cents per mile!

I'd log joyrides separately. For this comparison, I only want to log miles that I otherwise would have used the car for--that way I dont get an artificially inflated number.

Anyone made one of these calculators already?

 

[dogman dan]

Add it all up, and figure the battery should last at least 5000miles. Hopefully much more, but not if you won't ride that far in 2-3 years.

That should get you into a cost per mile for the bike, then it's just simple math. It can be as low as 15 cents a mile, but often is more if you spend a lot on the battery to go fast.

The one thing I could never figure out just how to value it. But my ebike commuting made a car in it's last year go 4 years instead. Calling that half the car payment for 3 years saved seems reasonable. If nothing else, it sure delayed that cost, leaving that money in the budget for other things.

In my case, while I still commuted, I was putting 12 bucks in my pocket every day I rode. Plus whatever making that car last longer did for me. It was enough money to go racing with ebikes.

 

[wesnewell]

My 2010 car has depreciated $8K with only 6K miles on it. Add insurance. tags, gas, etc, and cost to operate it is over $2 per mile. My ebike cost under 5 cents per mile total riding an average of 3.5K miles per year.

 

[trav]

The operating cost of your bike is dependent on your cost of electricity, plus any additional maintenance that the bike may need. You could keep a log of how many kw-hours your bike will use and multiply it by the cost per kwh on your electric bill.

Or, do it empirically. Let x equal the number of miles traveled.

For a car, the cost function is approximated by:
C(x)=0.5x

For a bike that has a 20 mile range at 48 volts with a 15 ah battery, assuming the initial expense of the bike is 1000, and if electricity costs 0.33 dollars per kilowatt-hr,

(48 volts × 15 amp-hr) = 720 watt-hr = 0.720 kilowatt-hr

20 miles / 0.720 kilowatt-hr = 27.7778 miles/kilowatt-hr

(0.33 dollars/kilowatt-hr) / (27.7778 miles/kilowatt-hr)=0.0119 dollars/mile

Thus, the cost function for a bike is

C(x)=1000 + 0.0119x

Equating the cost functions and solving for x,

0.5x = 1000 + 0.0119x
0.488x = 1000

x = 2048.68 miles

Therefore, with all the given factors, you need to ride the given ebike for about 2050 miles for it to equal the cost of driving a car.

Note: this model is insanely simplistic, and does not take things like maintenance, depreciation, or inflation into account. I think 2050 miles is a pretty decent estimate though.

If you really want to know, log your miles driven/fuel expenses for the car, and do the same for the bike, figure out the total cost, and note when the bike becomes cost effective.

 

[motomech]

To me, comparing the cost per mile to a cage is meaningless.
If Ebikes didn't exisit, I would do what I did for over 50 years, ride a motorcycle, now, that would be a small bike, or scooter, probably Chinese.
One of my last gasers, was a 50cc Eton Beamer scooter. I bought it off a collage kid who had parked it for $500. And I put another $200 into it(battery, big bore kit and new muffler).
It would do 47 mph, got 80 mpg and at the time didn't need reg., insure. or plates.
Even at today's gas prices, I would haVe to put many 1000's of miles on my Ebike to even come close to the cost per mile of that scooter.
For me, it's the qualities and nature of Ebiking that outweigh the expense.
"Silence is golden."

 

[Ussyamoto]

Here ya go, got bored and threw this together. Let the games begin!
My current info is in there for a reference.

Let me know what you think and if you think I can change or improve it in any way.

https://docs.google.com/spreadsheets/d/13bz9CxDh2atnt3Cuv9ucQjOlqJeq4aREReMH-ihLXAc/edit?usp=sharing

 

[Ussyamoto]

Warning, Post hijack!

Please post what you get for Current cost per mile and how much have you saved in fuel
I'm curious on what others will get.

I'm at:
Current $/mi: $2.74 USD
Fuel savings : $114.39 USD

 

[dogman dan]

I'm just like Wes. I did replace my car finally, and now I pay $450 month plus about one tank of gas or less, for a car I drive at most twice a week. Thats when I go someplace with the wife. Add the depreciation to that actual bill, and I don't want to know what it's going to cost.

But the plan is, this new Subaru will take me 200,000 miles eventually, and I'll have years of use of it at low cost starting in 4 years. A big part of the plan is ebiking enough to avoid having 100,000 on it by the time it's paid for. Looking at it that way, I don't see the depreciation costing me much if I keep the car 20 years. Depending on how things go, I might trade it for an electric car at some point.

Re the cost of the ebike, the electricity cost is so small it's barely worth calculating. The cost per mile of your battery is where all the money is. The motor should last 10,000 miles or more if you run a reasonable wattage. tires and tubes do cost a lot over time, especially if you have roads like mine, covered in nails and sheetrock screws from the contractors trash trailers.

 

[Melbourne]

You forgot to add Health Benefit to the spreadsheet.

-Lower blood pressure
-loss weight
-reduce chance diabetes
-lower chance of heart attack
-lower cholesterol?
-lower chance of cancer?

 

[BikeFanatic]

Did you add savings for parking, where I work in the city it costs 1000-2500 or more to park your car at or near work, and most people pay it.

maybe you could share the file with google docs- I'm sure many people here are interested in calculting their savings.

 

[Kingfish]

4x4 ICE Truck: Averaged 12k miles/year at about $400/month with tax, title, insurance, fuel, etc. The truck was paid off a long time ago: Original cost, including loan fees was $25k in 1995 dollars. At 170k+ miles, it has close to $20k in improvements, upkeep, and overhaul.

EV Investment: > $20k USD, amortized over 5 years. Distance: > 10k miles since 2010. Created 2 units: Converted one hardtail into a FWD and built a second F/S 2WD from scratch. New Energy costs: EV averages < 2k miles/year unless I go touring. Presuming I charge the worst possible electric rate at $0.125/kWh, it costs < $0.005/mile; a negligible value relative to the investment.

Summation:

• Truck averaged $0.40/mile, but does not include original costs and upkeep (though guestimating an additional $0.265/mile).
• EV, with investment costs, but discounting negligible energy at the end of 5 years will average about $2.00/mile. This value will continue to drop until the batteries need replacement.

Conclusion: You can’t compare these 1:1 because the context is not the same. I could take my truck anywhere, plus pull the moon to boot. The EV is a personal vehicle with limited abilities and capacities. The EV will always cost more until we get an infrastructure in place equal to ICE, and then the critical costs must come down, i.e. Battery and Motor.

Caveat: Should I change my riding habits towards having greater mileage, then the return on investment will be much quicker. Additionally, the math suggests that a small eCar or eMoto is a worthwhile investment on par with ICE. An electric 4x4 Truck is not... yet :wink:

Putting on the charge, KF

 

[80for20]

I live in the greater Vancouver area (home of ebikes.ca). Traffic is brutal. An electric bike lets me shave a minimum of 30-40 minutes off of my daily commute (can be FAR more if there is a traffic snarl up somewhere).

I'm not sure if you are considering time as a cost in your calcs. If you have to contend with heavy traffic, maybe it is worthwhile assigning some notional amount to lost opportunity. Especially if you work in a role where time is money (i.e., work harder and get a bigger bonus)

 

[Taiden]

Back of the envelope, I figured an ebike would cost $0.04 to $0.06 a mile if you were spending for a commuting tool. With any hobby, once you start going nuts doing all sorts of projects for fun, that will go right out the window.

The ebike I was gifted is slow but it commutes just fine. The cost on that is $0.0005 a mile RIGHT NOW because I didn't pay for it, and I charge it half here and half at work, which halfs the $0.001 cost of electricity I put into it since my house has five tenants and we split the electricity evenly. :wink:

As soon as I build something more capable, it will go up to about $0.04 a mile AFTER 40,000 miles of travel. Put if you consider resale on ebike components seems to be about 60% of new at the low end, you could argue it's less than $0.02 a mile.

 

[Ussyamoto]

Did you add savings for parking, where I work in the city it costs 1000-2500 or more to park your car at or near work, and most people pay it.

maybe you could share the file with google docs- I'm sure many people here are interested in calculting their savings.

Google docs link, first time using this
https://docs.google.com/spreadsheets/d/13bz9CxDh2atnt3Cuv9ucQjOlqJeq4aREReMH-ihLXAc/edit?usp=sharing

I've added a spot to put in parking costs as well now, thanks for the idea. I'm going to start a new post for people who are interested.

The Document contains:

Total bike cost calculator
Total current bike savings, cost per mile, cost vs using the car.
Total est savings after 1 year, cost per mile, cost vs using the car.

Calculator to find Electricity cost per mile/for 1 year.
Calculator to find Fuel cost for the car per mile/ for 1 year
Calculator to find your average car cost per mile/ for 1 year

Average car cost calculator contains:
Fuel $/mi
Maintenance
Tires
Insurance
Government fees/taxes
Depreciation
Monthly payments
Parking costs