Energy efficiency of active travel (walking, cycling, ebike) compared to an electric car
Energy efficiency of active travel (walking, cycling, ebike) compared to an electric car
137 comments
-
Maybe the most surprising thing here is that regular biking is still twice as efficient as e-biking even given our mediocre metabolic efficiency and a physique that isn’t exactly designed for the bicycling motion.
-
It makes sense to me...
For example if the the e-bike rider had to spend 1/5 of the energy of the unpowered cyclist (numbers chosen for the example's sake) that would be 1.1Wh/km they exert.
The remaining 12.9Wh/km would be what was discharged from the battery while riding (from using pedal assist and/or throttle features). This can be measured when you charge it back up at the end of the trip to the previous level.
-
Looks like trains are about 50wh/km
https://www.linkedin.com/pulse/most-energy-efficient-mode-zero-emission-urban-transport-kme%C5%A5
I couldn't find any info on planes, but that'd be interesting to see how massive that would be too.
-
Really had to drop that car speed down to make a meaningful chart huh?
-
Wdym? The faster a car moves (or anything, not just a car) the less efficient it's gonna be, because it has to fight against more and more wind resistance.
-
The measure of productivity of transportation is distance traveled, not speed (unless this were some time race). Comparing kw/speed tells you nothing about the kWh used to make the same trip as alternative modes of transportation.
-
In theory I agree, in practice other stuff, as the need for heating/cooling, really muddled the theory and puts the sweet spot speed way up. And if we turn the Aircon off, 150 is a really high number.
-
Wdym? The faster a car moves (or anything, not just a car) the less efficient it's gonna be, because it has to fight against more and more wind resistance.
That isn't entirely true. At lower speeds there may be other inefficiencies that are worse than wind resistance (since wind resistance becomes negligible at low speeds).
It will depend on the vehicle, but for example, small gasoline cars are more efficient at 70 km/h than at lower speeds. Electric vehicles will likely be more efficient at lower speeds (40 km/h) than gas vehicles, due to (lack of) gearing but there will still be low speeds where they are less efficient than higher speeds.
https://www.researchgate.net/figure/ehicle-energy-economy-at-different-speeds_fig1_326822085
-
Besides the other comment being right about air resistance, a speed of around 40 km/h is considered safe in urban environments and artificial obstacles are now being placed to lower traffic speed to about that limit. Also, the mean speed is also around that in towns where you either go faster than the limit or go 0 in a traffic jam
-
What would the energy usage be if all of them were going the same speed?
-
More importantly, the KWH used to go the same distance. Sure a car uses more power... It's going faster, and gets to its destination faster, therefore using power for less time.
Energy is measured in KWH, people. But yeah, your point about normalizing to the same speed to make the comparison fair is good.
-
-
It's still inaccurate though. Even at (slow) highway speeds my Ioniq uses slightly less than 150wh per km, if I drove a constant speed of 45km/h I could easily hit under 80wh per km
-
-
Yeah, micro mobility is great on paper when you’re young and live in an accessible city with flat topography. Years ago I became (and still am) a bicycle commuter and I am ENTIRELY SICK OF IT. I want a fucking car. I am tired of biking in the rain and the snow and the cold. It fucking sucks.
Also If I didnt have the ability to purchase an e-bike recently I’d be fucked with the terrain of the place I am currently stuck living (and even that doesn’t quite cover the situation).
Also I am tired of minor injuries compounding year over year due to the simple fact that I am using my body as both the engine and support structure to move myself, vehicle and cargo around just to live.
It was fun 10 years ago but now I’m just like give me a fucking cargo van.
-
I've been telling everyone how most people don't need a car in a big enough city (I'm in Europe), and how much more efficient (PROPER) public transport is.
...And then I get the work commute metro trains where stupid/inconsiderate/disgusting people still get on the packed train despite being sick, keep standing in my kidney and sneeze/cough at others (without a mask, of course) and sniff their nose all the way. Every single time when that happens I dream about having my own car where I don't have to deal with this (or an idiot blasting TikTok from their speakers, being drunk+loud, smelly, etc.).
I still won't have a car, but man, sometimes the right decision isn't the easiest.
-
I live in a city with very good public transport which I use constantly. I also have an E-bike.
However, one needs to note that if I buy something big (extra lot of groceries, a new computer, a painting, anything that doesn't fit in a backpack), using PT is pretty inconvenient. Especially when I'd be faster just carrying the thing home from Ikea, since I only live some 2km away, but the bus routes don't go across the boroughs (but radially from the center outwards, with a few "lateral" buses), so I'd take two buses and it'd be some 10km. And if it's raining and I have an item that shouldn't get wet...
Also, taking a cat to the vet for instance.
I'm just waiting on when public transport will be supplemented with small city EV-s you can rent for a few hours cheaply. Like those e-scooters, but small cars, and with more regulations.
I know an apartment building which gives the tenants (mostly young students) the option to reserve and rent an EV for just a few euros an hour. And you don't need to fill the tank, so it's pretty nice.
-
-
Had a neighbour in his 80, had multiple leg operations and he still used to take a daily bike ride to keep fit. Not to mention that even if bike commutes suck, they improve your mental health considerably, even if you go in the rain/cold.
And most importantly of all, those who can take the bike cover those who can't. So please enjoy your car ride, but take the bike when you can.
-
Do you personally commute by bike 100% of the time for literally every outing to get to work or run errands? Because I do, and have for a decade. I’m over it.
-
-
Also I am tired of minor injuries compounding year over year due to the simple fact that I am using my body as both the engine and support structure to move myself, vehicle and cargo around just to live.
I'm sorry you're getting pushback and criticism for this. As someone who physically can't bicycle and struggles with mobility, I strongly support well designed and well maintained walkable communities, bicycle infrastructure, and effective public transit. And I recognize that, for some people, the basic right to travel and work and generally function in society requires personal car ownership.
That doesn't mean I sympathize much with people who live in subdivisions off major highways with no grocery stories within twenty miles - there shouldn't be any community anywhere designed to require car ownership.
But I also don't sympathize much with people who want to ban all personal vehicle ownership from their little 15 minute utopias. Disabled people exist.
-
I agree with this. Cities shouldn't be car exclusive, but eliminating cars completely would also alienate villagers and people living in rural areas, in addition to disabled people.(written by an european who has family in those regions)
-
-
Sounds like it should keep you fit.
What kind of injuries?
-
I completely understand the weather thing. In the Netherlands it doesn’t get that cold, but the rain is really annoying (it rained basically non-stop from october till late february). In the city where I live however, there is also a pretty good bus service, so you can avoid cycling longer distances in the rain. For me I find cycling in good weather so good for my mental and physical health that I wouldn't want to go without it.
You say an e-bike doesn’t quite do it for you, and I'm curious what you mean. Is it that it doesn't have the range, that the engine isn't strong enough for hills, or something else? I would love to learn about more disadvantages of micromobility, so I can create more nuanced opinions.
-
I used to live in Boston, which in recent years has become very bike friendly and is actually setup to make sense using a bike for primary transport (fairly robust public transit for the US, physically pretty small), but now I live in a city in Massachusetts where the area has very little bike infrastructure, and the landscape is hills and valleys of hundreds of feet of varied elevation every half mile or so. Using a non-electric bike for daily errands / transport would be equivalent to running a marathon every time I need to pop over to the grocery store. The e-bike battery and range runs out so fast that i’m basically limited to a single specific errand every time I go out—no option for doing more than one thing. Also add to the fact that everything is designed around cars so amenities are not blocks away, but rather towns away.
The northeastern United States sees basically every type of weather so there are days where it’s wonderful to be out on a bike and days were it is a complete nightmare—when you have to get on your bike to get to work when its raining sheets or 10 degrees (Fahrenheit) outside and there is no other option it becomes a wretched ordeal.
My point is, beyond a very specific set of circumstances where weather, health, topography, public transit infrastructure and also the immense luxury of even being able to live in a city all line up, using a bike as a primary mode of transportation is completely useless solution.
-
-
Preach it.
I am old enough where these sorts of points have much heavier weight. I can bike, but my body is not happy after any non-trivial distance.
I now have my eye on an electric recumbant trike. It solves all of my ergonomic (back) issues, and the electric would help with some of the terrain struggles and help me more accurately predict travel time. Plus, there's a bit more storage for, e.g., a change of clothes for the destination. They're damned expensive, though, even the cheapest.
Doesn't solve the weather issue, but I'm sure someone makes a version that has a shell; at which point you're essentially just driving around a small, slow, electric car with a lot of limitations.
I'm still going to replace my bike with a recumbent, though. My body just can't handle that position for prolonged periods anymore.
-
-
The car is correctly represented, about 0.15 KWh / km is what one gets.
However, the positioning of the e-bike looks strange to me. I've looked at previous studies and the e-biker has always been first in efficiency - because the efficiency of a motor far exceeds the efficiency of human digestion and muscles, while weight and speed remain comparable to an ordinary cyclist.
I think someone has calculated food energy incorrectly, or assumed that e-bikes move faster than they do. :)
-
I guess it's hard to gauge an e-bike since they often have a variety of operating modes ranging from progressively higher levels of pedal assist up to full throttle. But that's fascinating to think that an all-electric ride may actual consume less energy in the grand scheme of things. I had never looked at it that way!
-
It is interesting, but remember we need food to live anyway, and we need exercise to stay healthy. If we ask used ebikes on max pedal assist to get around, but then go to the gym and pound the treadmill for an hour, what does that do to the numbers? Or if we eat less and burn less energy, but then lose bone density and need more healthcare as we age (just one effect among many of not getting enough exercise)?
-
-
I think many people peddle just as hard on an electric bike, so the 5.5 kWh/km is a given, the rest is the energy required to go faster. Since air resistance increases with the square of the speed, it might very well be the case that 14 kWh/km at 25 km/h is more efficient than what the human alone would need to deliver for the same speed.
Edit: I failed to take into account that for the human at the same level of effort the power remains constant, not the energy per kilometer. Going faster at the same power output would reduce the energy expenditure per kilometer for the human to about 4 kWh/km, which would indicate that 10 kWh/km is being delivered by the motor to go faster.
That being said, it might be the case that they just calculated the energy needed to move the bicycle without taking the energy efficiency of the digestive system into account.
-
I just did a quick of my statistics. My bike typically provides an average of 100W in my hilly 28km commute (both ways) that takes about 1h15 minutes. That's less than 5Wh/km.
I'm using a fairly high setting, too, and judging by the fact that I don't break a sweat at all, I'm 100% sure I'm not pedaling as hard as I do on a regular bike.
-
-
-
This would be much more efficient if it had other transportation as well.
Like non-electric cars, trains, subways, etc.
It's not too hard to get their efficiency as well.
NEXT DAY EDIT: Should've looked, there's actually a handy chart showing the energy efficiencies of a whole bunch of vehicles and modes of transport just straight up on Wikipedia. This article. Comparing the km/MJ column, we can see:
Walking 4.55
Velomobile with enclosed recumbent: 12.35 (there wasnt a figure for just regular biking)
Solar car: 14.93
Tesla Model 3: 1.76
General Motors EV1: 1.21
All combustion engines are below 1, but here's a few:
VW Passat: 0.33 Cadillac CTS-V: 0.17 Renault Clio: 0.42
There's a whole bunch of other stats though so I suggest checking the table
END EDIT
-
Also biking and walking are not necessarily even viable for certain commutes such as any over about 4 miles/ whatever that is in kilometers say 8, and anytime I need to carry heavy luggage / groceries. Or anytime anybody with mobility issues needs to travel.
It's all very well insane if we wanted to buy an e-bike and get rid of their car but that's not really practical.
-
The break-even distance in urban areas, where it takes the same amount of time to bike, is typically more like 7 miles. That's about half of commutes. Not a 100% replacement for everybody, but big enough to make a meaningful difference.
-
<7km is too far to bike?
Oh man. Well, I agree on the other things you said, but... 6.4 km isn't that much. It's a fair bit, yeah, but not that much. With an e-bike, it's not really even a thing. I chose to use the healthcare in the next city over (I live on the border of two cities) and I have about ~7km whenever I go there. 10-15 min with an ebike. With a regular one it'd be a chore, but it wouldn't take much longer, 20-25 minutes maybe with a loose pace.
But yeah biking definitely can't replace everything. I mean, cargo bikes exist, but still.
With mobility issues, we now have a lot of mobility "scooters" that go about 25km/h per the EU regulations. Like a super buffed up wheelchair. with a sort of chassis. Small enough to fit in the back of a taxi-van that has a disabled lift, but still quick enough to use in a similar way as a bike.
Still tho. I want my cheap rental ecars.
-
-
-
This should be shown in Km/Wh so the more efficient the modes of travel show as bigger bars.
-
yes, I thought it was backwards and was quite surprised
-
A lot of electric cars use that unit.
Well more like kW/100km
-
-
While I like this chart, it's useless without the tradeoff. It also needs to map speed to time spent. What is being given up for improved efficiency? The inflection point is how you move people from point A to point B.
-
The biggie is urban planning to ensure that people don't need to travel huge distances on a routine basis. That means that people give up very little.
-
-
This data needs to be normalized by speed or realistic range/day. Otherwise it's pretty meaningless.
-
It is totally pointless, I am totally on side of bikes and walkable cities, but this chart is pointless. What battery stores and what humans use is not comparable, and adding combustion engine car/bus/train here would throw the chart to totally other scale. Train has enough kWh to power a small town, but it carries shit ton of load.
-
Like most "fuck cars" memes it's only relevant if you're a young single person with no hobbies who never travels more than 5km from their home without taking public transport.
-
-
Energy efficiency and carbon footprint are very different things - pretty sure the carbon footprint of 15 big macs (8500kcal) is substantially greater than 1L of gasoline (let alone an electric grid equivalent)
-
A quick googling tells me a burger is about 3kg of CO2 equivalents. 1L of gas seems to be about 2,5kg.
Now if you were to eat local and seasonal food I'd guess you can get more efficient than burning oil.
Edit: As @bjorney correctly pointed out a quick google in the morning, before the brain functions properly kick in, isn't the best way to produce comments on numbers. I did NOT account for the factor of about 15 that a burger needs to get close the energy stored in a liter of gasoline.
Edit to the edit: Just out of curiosity I did another quick google (please brain, be functioning now) and it seems that to get 8500kcal from oats you need about 2,5kg. This seems to produce about 1kg of co2 equivalents. I am certain that this does not include the amount of co2 the human is expelling in excess by using their muscles instead of a motor, so the whole discussion is probably moot anyways.
-
In this regard, a vegan cyclist is going to beat out anyone in a car.
-
-
Now do one where you A) normalize this to the same trip distance (not speed, so that these choices for a single trip become meaningfull) and B) convert the kWh into CO2 emissions, including the emissions in growing and transporting the various power and food production methods used (coal to solar, locally produced veggies-air shipped beef)
-
It's already normalized to distance, the graph is showing kWh/km. The speed is just there for additional context.
-
Trip distance is dependent on methods of transportation at the aggregate level. That's only relevant for policy decisions or collective actions, not individuals of course, but if we are going to deal with climate change, collective action is necessary.
Given the graph is normalized by km traveled, its overly generous to cars.
-
Yeah, if you account for the amount of CO2 that goes into producing food the ebike will be much more efficient in terms of co2/km than a regular bicycle. Even if you cheat by making the regular bicycle drive slower than the ebike, like they did for this chart.
-
-
Interesting. I've never owned an electric car, but just guesstimating based on those numbers, my daily commute would cost something like 25 cents in electricity. Not too shabby.
I did buy an ebike a few years back and watched to see how much the bill went up, but frankly never noticed any change. At 2 cents per day, it's basically a rounding error relative to other electrical usage, so that makes sense to me now.
-
Let me just travel 30km to the shops by foot and carry shopping home another 30km back again
-
Have you heard of this miraculous thing called public transit? And there are things called panniers which are pretty cool too.
But frankly, if you don't have groceries within walking distance, your neighborhood and your zoning laws are very poorly designed.
And that's deliberate. Neighborhoods around the world are designed to require cars to live in, because of oil company lobbying, and also for "security", in order to keep out people too poor to own cars.
Getting rid of cars requires changing the various ways our cities are designed to make cars necessary. That's worth doing too.
-
Living outside land of the free, I have like 4 grocery stores and 1 supermarket within 15min walking distance, and I don't live in a dense neighborhood.
-
Can confirm. It takes an hour to walk to the city. I have 3 grocery stores within 10 min of walking (checked with Google maps too)
-
-
Also carry 4 other humans with you when you go
-
-
Thanks a lot for linking the source!
-
you're welcome. It's something I try to do routinely.
-
-
Where's the gas car on here? How about steam locomotive?
If I've got to go 300+ miles through the US I'm probably not going on foot or by human power.
-
If you need to travel that distance, take a fucking train.
-
Lol. Sounds good. My little brother lives in Birmingham, AL and I live in West Lafayette, IN. My sister lives in Fishers, IN and my in-laws are at one of the northernmost suburbs of chicago. I invite you to propose me travel solutions for my wife and two children under 5 which are better than my electric car.
For reference:
West lafayette to Birmingham: 875 km
West Lafayette to Fishers: 112 km
West Lafayette to North of chicago: 260 km
I would LOVE to take the train or bike or walk. But I think people like you and OP might be underestimating the hostility toward (and unavailability of) public transit in the US outside of Metro areas. I appreciate that there are better answers than my electric car, but it's better than getting in my double wide and double tall diesel truck, no?
-
-
-
This should include gas cars too which are ungodly inefficient
-
EBikes are awesome. I live in a hilly area where riding is tough. EBikes allows people of all ages and abilities to get out. Even with the assistance you still burn calories... as long as it's assisted peddling and not the illegal bikes I see delivery guys riding.
I ride road bikes but when I get older and less capable I'll certainly invest in an ebike.
-
I don't begrudge the deliverers their powered bikes, they have a tough enough gig and it's one less car. I do wish e-scooters would stop going fast among foot traffic though. My kid moves pretty unpredictably, and has had near misses in pedestrian areas
-
-
My ebike goes 40 km/h.
-
I believe most e-bikes in Europe are limited to 25km/h. 32km/h in Canada.
-
I'm in Canada and my e-bike does indeed have a 32km/h limiter. I was a little amused, though, to discover that there is a phone app which can lift this limit, so it appears to only be in software. But I have left it at 32 regardless. I'm perfectly happy with that.
-
same in australia
-
-
Mine goes up to 35 km/h when is freshly charged, down 75% of battery to 30 km/h.
-
-
-
-
Time efficiency in a modern urban area optimized for public transport and non-motorized transport modes compared to time efficiency in current typical urban areas, which are focused on individual motorized transport modes with severe lack of public transport:
[Fancy chart: first case left, second case right]
[Good] [Bad]
-
-
Time us is so heavily dependent on location you cant standardize the data effectively
-
I get what you are trying to ask, and why, but unfortunately, such a comparison is not so trivial:
Setting aside load (weight) and age differences, various transportation means use gear shifting in order to adapt the power output to the characteristics of the current load (as in "system load" this time). This adds a dimension of dynamism to the comparison, and most vehicles do not automatically and systematically impose an ideal efficiency constraint on the power output.
To illustrate, using a single speed bike requires vastly different power than using a 7 speed bike. And different driving styles will radically change the efficiency of combustion engines.
So, in addition to mapping the efficiency to various speeds, it should be mapped to various use cases (hence why combustion engines have different fuel economy in "urban" and "extra urban" situations).
In the end, the graphic would not be 2D like this one, or 3D like it would be with "time per km" (or mile) vs energy requirement, and per type of vehicle, but there would be several 3D graphics, one per vehicle type, with time per km vs environment vs energy consumption.
TBH I was gonna try and do that, but even with ADHD, I can see this is going to be mad time consuming. So yeah, no, I think I'll pass. Good idea tho. "Someone" should do it. 😇
-
-
Yeah but what about if a person is a massive hambeast? Ain’t no cycles going nowhere under that strain.
Or what if they are a massive douchenozzle chud fuckwit?!? It would emasculate them to not have the largest most unnecessary truck possible?!?
-
-
Oh there’s always a genuine, non-sarcastic use for a car. I’m close enough to work to cycle without blinking, yet scheduling and family pressures / drop-offs/ pick-ups mean that it’s more time-sensible to drive.
I hate it. I used to cycle every day to work.
The other shitty thing in the equation is the public transport which functions at a generous 40% of what it might.
I’d hate to wrap my soggy brain around solving the problem, but I wish someone would; more routes, more frequency, more funding. = fewer cars.
-
-
I feel seen
-
-
Keep in mind that although an electric bike might use more energy input than a regular road bike, it uses a much cleaner type of fuel. Even the most dirty coal power plant in the world has a significantly lower CO2 output per watt hour than the food you are eating to power a bicycle. Even if you are vegan
-
Wrong.
Coal power has a CO2 intensity of ~1 g / Wh (source: IEA)
A plant based diet has a CO2 intensity of ~1 g / Wh (source: ourworldindata)
Production CO2 intensity of a bicycle is also lower than an e-bike.
Pedaling under your own power also has health benefits, which the e-bike rider would need to do additional exercise to achieve, thus increasing their total CO2 intensity further.
In short, sit the fuck down and shut the fuck up about shit you clearly don't understand.
-
A plant based diet has a CO2 intensity of ~1 g / Wh
Yes, and since our metabolism is very inefficient you actually need to eat almost 4 watt hours worth of food for 1 watt hour of energy output, everything else just turns into body heat. Meanwhile ebikes have an efficiency of roughly 70-80% when accounting for charging losses and motor efficiency.
-
-
We should probably just stop eating.
-
-
Now do it at the same speed.
-
What sense would that make?
-
-
How does biking or walking consume energy ?
-
You burn calories when you exercise
My 30km round trip bike to work burns about ~800 calories, or 1.33 big-mac equivalents, which has a carbon footprint of about 4.2kg CO2
That same round trip would burn 2L gasoline in my car, which has a carbon footprint of about 4.6kg CO2
-
Edit: I see where you are getting your numbers now after looking around. I will leave my comment here for sake of others seeing it and the discussion.
How are you getting 4.2 kg of CO2 for 800 cal???
The average estimate is 0.35 per 1000 cal for the more eco friendly
https://ourworldindata.org/grapher/ghg-kcal-poore
https://www.globe.gov/explore-science/scientists-blog/archived-posts/sciblog/index.html_p=183.html
If you are eating stupid amounts of meat every meal, sure you might average that high.
And more than that, the food is just CO2, arguably not as bad of a GHG. the petrol/gasoline also has the really bad stuff people don't bring up as much, such as the nitrogen-oxides and sulfurs.
-
-
Food tends to have significant energy inputs in the form of methane gas used in the production of nitrogen fertilizer, diesel tractors, transportation, and cooking
-
Gotcha
-
-
137 comments