I am a bike commuter, and I’ve heard a lot of others who commute by bike saying that one of the biggest reasons they bike is because it saves money on gasoline. Some also go a step further and say that this reduction of gasoline helps the environment, too. But I’ve always wondered: is this really true? After all, food is expensive, and also a leading contributor to CO2 emissions!
Here’s a quick calculation based on prices where I live (Seattle):
## Cost of fuel
Biking exhausts calories at a rate of about [50 kcal/mi](https://www.livestrong.com/article/135430-calories-burned-biking-one-mile/) in excess of sedentary existence. If you eat a Big Mac (590 kcal) for $7.04, this is **$0.60/mi**. If you eat a Wendy’s JBC Biggie Bag (940 kcal) for $5.51, this is **$0.29/mi**. If you just eat an entire loaf of Trader Joe’s white bread (1540 kcal) for $2.19, this is **$0.07/mi**.
The average gas-powered car runs [at around 25 mpg](https://www.epa.gov/automotive-trends/highlights-automotive-trends-report) or 0.04 gal/mi. At $5/gal, this is **$0.20/mi.** The average electric vehicle runs [at around 3 mi/kWh](https://justwe-gpi.com/ev-charging/electric-car-mileage/) or 0.33 kWh/mi. At $0.12/kWh, this is **$0.04/mi**.
The conclusion is that the cost of “fuel” for biking actually exceeds that of cars if you always eat out, and lies somewhere between a gas-powered car and an EV if you cook at home.
## CO2 emissions
The average US diet emits [2.2kg CO2 per 1000 kcal](https://www.tabledebates.org/research-library/carbon-footprint-and-nutrition-self-selected-us-diets) consumed. At 50 kcal/mi, this is **110g CO2/mi**. Of course, this number can be greatly reduced if you are vegetarian.
A gallon of gasoline emits [8.9kg CO2/gal](https://www.epa.gov/energy/greenhouse-gases-equivalencies-calculator-calculations-and-references). At 0.04 gal/mi, this is **356g CO2/mi**.
Seattle’s public electric utility [is net-zero](https://www.seattle.gov/city-light/environment), running mostly on hydropower and buying carbon credits to offset the 3% of its portfolio which relies on fossil fuels. An electric car thus emits **0g CO2/mi**. The national average is [433g CO2/kWh](https://www.epa.gov/energy/greenhouse-gases-equivalencies-calculator-calculations-and-references). At 0.33 kWh/mi, this is **144g CO2/mi**.
The conclusion is that the CO2 emissions of fuel when riding a bike are comparable to that of an electric car depending on your diet, but if your electricity comes from carbon-free sources, an EV is obviously better.
## What are correct reasons to commute via bike?
I need to emphasize that I am a bike commuter, and I agree that more people should be biking to work! But I was still surprised by these calculations. We shouldn’t ignore them because these are facts that bike opponents can also cite. In light of this, I wanted to point out some deficiencies in the above calculations and list some other reasons why biking is good. (In other words, you should say the following if someone asks you why you bike, not the above!)
* Cost of fuel is not equal to cost of ownership. [Fuel is only a small portion](https://www.bts.gov/content/average-cost-owning-and-operating-automobilea-assuming-15000-vehicle-miles-year) of the price of car ownership, and the vast majority is the base price of the car, taxes, interest, insurance, and maintenance. Plus, eating makes me happy!
* Direct CO2 emissions based on fuel is not equal to total lifetime emissions. The manufacturing process of a car, the road infrastructure, and the construction of parking spaces needed to store the call all represent additional environmental costs of car ownership. (Though I could not find studies that calculate how significant these other factors are.)
* Environmental impacts are not limited to CO2. For example, rare earth metal mining for large batteries in EVs pose a significant environmental issue as well.
* People who commute via bike typically choose to live closer to work. (You can choose to live close and drive a car, but for some reason most people don’t.) This skews the per-mile analysis of the above numbers, because people aren’t biking as far as they drive anyway.
* Biking is healthy. By investing in your body, you can also save on medical bills down the line, and reduce cardiovascular risks. You can also save time by reducing the cardio you do at the gym. (Note: [A survey of existing literature](https://pubmed.ncbi.nlm.nih.gov/21496106/) found that biking improved fitness and reduced cardiovascular risks, but its effect on mortality, obesity, and cancer remain inconclusive.)
by yadec
25 Comments
Nice job
I’d be interested to see how various kinds of e bikes compare. I’m guessing they’d be about the same since you found that acoustic bike and electric car are about the same.
“Fuel” for biking should be only what is in excess of normal and specific to biking. That big mac is only relevant if it was specifically consumed for biking and not just lunch.
I think your averages are a little high for mpg and m/kwh.
https://modmo.io/blogs/news/what-is-the-carbon-footprint-of-an-ebike
Here is an interesting article on the subject. How the electricity is being produced to charge the ebike battery would be a factor of course, but the assist from the battery actually edges it past a regular bike for efficiency.
Cool to see just how much more efficient it is than walking
You’ve eliminated the kcal burned while driving.
Driving is an average 150-250 kcal per hour (passengering is 80-130 per hour)
Interesting. Not as large of a difference as I would have thought. Might dive into the numbers later
Food is a renewable resource, inasmuch as it comes from plants/animals that we grow/raise and then harvest/slaughter. Petroleum is a non-renewable resource. Electric vehicles are a bit of a “maybe,” because it depends on the local utility’s mix of renewable/non-renewable energy sources.
I need to exercise, probably more than I already do, so biking really just takes from that budget, its effectively zero sum for me. If someone else religiously goes to the gym regardless if they commute on their bike then I agree on your analysis being applicable, although there is an energy cost to driving, being alert/awake, etc.
I’ll only add that food tastes way better than gasoline or electrical wires! 🤣
The above points discussing BMR and food types, plus e-bikes using far less electricity than electric cars are all good 👍
The big issue is that you’re not factoring in the fact that humans already need most of the calories you’re expecting. I don’t have specific numbers, but I am positive that cycling doesn’t add a need of more than 30% daily calorie intake.
Also, it is important to realize that a very large percentage of a cars lifetime emissions are actually created during manufacturing.
You choose energy-intensive food. It’s not a fair comparison.
lol this sub never ceases to amaze me at how hard we try to justify bike commuting.
Maybe I’m in the minority that finds riding my bike to be the main motivator behind riding my bike. I do have the luxury of affording a vehicle, so I’m sure that’s a huge factor.
Thorough try, but in a misguided way in my opinion.
1. Fossil fuels has to be completely phased out. Gas can never be fossil free, food production causes emissions partly because of fossil based transports that will have to be changed in time. Food production varies from emission heavy to very emission light. EVs are better than ICE cars but still very resource intensive with high production emissions.
2. Exercise is needed for everyone to be healthy. Active transportation causing the burning a few calories can’t be counted in a vacuum.
3. I have compared production emissions of a few different vehicles. An EV like Polestar 2 emits over 30 times the amount of a large electric cargobike (Load 75). A combustion car can still easily cause the emissions of 20-25 large electric cargobikes. Comparisons between a car and a non-electric bike means hundreds of bikes to reach comparable production emissions.
This can be continued forever. Don’t fall for bullshit comparisons of cyclists eating heaps of pure beef to be able to pedal around instead of sitting still and conserving energy. That is a scenario clearly meant to twist around reality.
Fossil fuels are a cancer killing the future of our species. If you are decreasing or stopping your car dependence by taking the bike you are helping creating a foothold for a very energy effective transportation mode that easily can work in a world without fossils, while a car dominated transport system is very hard and expensive to completely electrify.
Biking is good for you and the planet, there is no genuine doubts about that.
Some references regarding production emissions:
Life cycle assessment —Carbon footprint of Polestar 2, s. 20.
XC40 ICE petrol: Materials production 14 ton + Li-ion battery modules 0 Manufacturing 2.1 ton + End-of-life 0.6 ton = 16,7 ton CO2e
PS2 LR: Materials production 17 ton + Li-ion battery modules 7 ton + Manufacturing 2.1 ton + End-of-life 0.6 ton = 26,7 ton CO2e
Riesse & Müller On the move together Responsibility Report 02, s. 96:
Delivery 74.71 kg + Production 696.64 kg + Packaging 10.07 kg + Shipping 4.82 kg + Disposal 43.83 kg = 830,07 kg CO2e
If you are overweight you already have the excess calories to burn! If you adopt a plant based diet grown with regenerative organic techniques you are Carbon negative in your fuel. I agree with all your other reasons, but cost of “fuel” assumes an unhealthy diet which won’t provide you with the premium benefits.
Peanut butter is $7.90 for 2kg (12000kcal), or **$0.004/mi**
you are calculating the CO2 generated at the tail pipe. Oil needs to be drilled, pumped, pipelined, refined, and rrucked before it reaches a car. Allow of those process take energy and are powered my mostly fossil fuels. Initial googling says to add an additional 24% diesel and 30% gasoline of CO2 produced per gallon.
Next, it takes a lot of steel and plastic, to make an ICE and a lot of lithium and cobalt to make an EV. Those need to be factored in for CO2. The materials to make an e bike are the same for an EV but are dramatic less 89 lbs for a Heavy ebike vs 3500 lb for a light EV. A bike classic ™ is even better at 25 lb of materials vs 2000 lb for a typical ICE.
On food, we want humans. and humans need to eat. It is better to spend our financial budget and Carbon budget on maintaining and making humans rather than maintaining and making cars.
There are other costs to save on by bike commuting including registration, insurance, parking, storage, maintenance, depriciation. And there are society saving costs including costs related to health care from car crashes, health car costs relating to decreased air quality from car emissions and car tires, damage to roads and other infrastructure.
The biggest issue with this calculation is the assumption that Co2 is bad for the environment. There is no way in hell that exhaling is poisonous to the environment, so these calculations are moot. Excess Co2 is not an issue currently, as actual greenhouses operates on over 1000ppm, so something tells me that more Co2 is better for plant life, which in turn, is better for humans.
You’re not thinking about a lot of other variables here, like the cost of manufacturing the car vs bike, the difference in damage to roads and infrastructure, the cost of building bike infrastructure vs car infrastructure, the waste produced after the car/bike’s lifespan.
How can a biker use 50kcal per mile?? Isn’t the typical caloric intake of a human like 10kcal per day max? (Unless you’re joey chesnut)
So my 5 mile commute is 250kcal? That’s like eating 830 donuts.
I dont like this math at all.
Do ebikes….
[Representative Orcutt?](https://inhabitat.com/washington-state-official-says-cyclists-emit-more-co2-than-motorists-and-must-be-taxed/)
On the cost side, you’ll find that the cost of good bike tires is more expensive than car tires on a cost per mile/Km basis. Unless you’re selling your car and replacing your car with a bike, bike commuting isn’t a money saver. Lots of good reasons to commute by bike, though!
Idk if we should count the food you burn as a bike commuter. Just because drivers aren’t burning those calories doesn’t mean they aren’t consuming them. Have you seen the obesity rate, recently? I’m not sure there’s much correlation at all between how many calories someone burns and how many calories they consume.
Yea for most people if we only look at the cost of fuel, gas is cheaper. Just like in this thread people miss the point. I always tell them this in direct response to when people say they are saving money on gas. They then explain all the other reasons commuting is good that I’m well aware of. You still aren’t saving money on gas though.
Asking some interesting questions here 🤔
So we shouldn’t exercise?