Electric Bikes - Which is greener? electric bike or human powered bike?

I've been having this debate on another forum, and frankly there are several people that are offended with the idea that an electric bike might be greener.

check it out if you like, but out of respect to this website, please keep all your comments here

http://www.freecbc.ca/cgi-bin/backtalk/backtalk.cgi/abalone/read?conf=general&csel=&nosee=1&item=538&isel=539-$&rsel=new&tmprsel=218-$

http://www.ebikes.ca/sustainability/Ebike_Energy.pdf <----- if you havent already seen it

Human powered is greener. But my co-workers might not think I smell very "green" when I get to work which is why I'm sticking to electric. :)

They are both 'greener' than anything else out there, except maybe walking.

Human powered is greener. But my co-workers might not think I smell very "green" when I get to work which is why I'm sticking to electric. :)

electric is greener...factor your food for fuel for your body...

peace wasp

electric is greener...factor your food for fuel for your body...

peace wasp

Depends on where that electrical power comes from. If from solar, then I agree. If from the power grid, maybe not.

Even if from solar, you have to weigh in all the manufacturing and transportation and setup of your solar charging station. Stick with it long enough to pay down the pollution caused by that, and you'll be greener. :D

Depends on where that electrical power comes from. If from solar, then I agree. If from the power grid, maybe not.

Even if from solar, you have to weigh in all the manufacturing and transportation and setup of your solar charging station. Stick with it long enough to pay down the pollution caused by that, and you'll be greener. :D

yes just like if my power was say coming from coal and you were growing you
own food...there are variables

peace wasp

electric is greener...factor your food for fuel for your body...

peace wasp

Doesn't compute. You're still eating food even if you ride an electric bike. :rolleyes:

did you guys even bother to read that PDF I posted a link to? your arguments are answered with citations!

After a 25 mile ride doing errands just pedaling I need some calories and a couple beers:) With the ebike just one pop or beer will do plus about 3 cents of electric charging:) Seems cheaper than human powered to me.

did you guys even bother to read that PDF I posted a link to? your arguments are answered with citations!

I did and it's nonsense. I eat the same quantity and the same foods whether I bike or eBike.
Human beings are incredibly energy efficient machines. No eBike battery/motor combo can beat it.

And like I said before: When a human rides an eBike, he still eats food.

Keep in mind that I'm only looking at moderate cycling. I don't race or train on my bike. I just ride it as a means of transportation or leisure.

So in my case, the human powered is "greener". But I don't care. I still use electric. I'm not an environmental hippie but I like to do my part where possible without compromising too much.

I eat the same quantity and the same foods whether I bike or eBike.

If that's true, you are very unusual. In general, you must eat fewer calories to maintain your weight, if you burn fewer calories during exercise.

And if you gain weight by burning fewer calories, the extra fat your body puts on will also burn calories, believe it or not. (fat cells require a small amount of energy to keep themselves alive).

The energy contained in your food goes somewhere and it's unlikely that it simply goes through undigested.

So, assuming you eat extra to power a human-powered bike, the energy is going to come from food. If the food is the typical, buy-it-at-a-grocery-store, "industrial agriculture product" that people eat in developed countries, then human powered biking is far greener than car-driving but still less green than coal powered e-biking.

Electric is greener - folks who are turned off by the distance of their commute for human powered bikes are probably using cars instead. Electric bikes makes it easier for the average person to decide not to use cars at all, and IMHO this far outweighs any cost that electric bikes have on the power grid.

normal bike=greener if you grow your own food.
electric bikes fill landfills with batteries and other more disposable parts than a regular bike.
Its not all about consumption, much of it is what you leave behind
Even with a solar charger, there are more parts to put in the landfill year after year.
This argument is silly, what is greener a small fan or blowing your own wind?

normal bike=greener if you grow your own food.
electric bikes fill landfills with batteries and other more disposable parts than a regular bike.
Its not all about consumption, much of it is what you leave behind
Even with a solar charger, there are more parts to put in the landfill year after year.
This argument is silly, what is greener a small fan or blowing your own wind?

show me a landfill that allows me to throw out sla's?
your speaking nonsence lead bats are recycled
and it's not a argument it's a discussion!
your words speak volumes if you want to argue
argue with your wife most people are DISCUSSING...

peace wasp

show me a landfill that allows me to throw out sla's?
your speaking nonsence lead bats are recycled
and it's not a argument it's a discussion!
your words speak volumes if you want to argue
argue with your wife most people are DISCUSSING...

peace wasp

ar•gu•ment--noun
1.) A reason or set of reasons given with the aim of persuading others that an action or idea is right or wrong : there is a strong argument for submitting a formal appeal | [with clause ] he rejected the argument that keeping the facility would be costly.

2.) An exchange of diverging or opposite views, typically a heated or angry one : I've had an argument with my father


dis•cus•sion--noun
The action or process of talking about something, typically in order to reach a decision or to exchange ideas. See agrument

syn•o•nym--noun
A word or phrase that means exactly or nearly the same as another word or phrase in the same language.

ar•gu•ment--noun
1.) A reason or set of reasons given with the aim of persuading others that an action or idea is right or wrong : there is a strong argument for submitting a formal appeal | [with clause ] he rejected the argument that keeping the facility would be costly.

2.) An exchange of diverging or opposite views, typically a heated or angry one : I've had an argument with my father


dis•cus•sion--noun
The action or process of talking about something, typically in order to reach a decision or to exchange ideas. See agrument

syn•o•nym--noun
A word or phrase that means exactly or nearly the same as another word or phrase in the same language.

couldn't answer could ya...
your words and lack of a answer shows
that your just trying to argue
wife not home?

peace wasp

couldn't answer could ya...
your words and lack of a answer shows
that your just trying to argue
wife not home?

peace wasp

I'm not Bikingtoteach.

Lead acid batteries should be recycled.

Argument and discussion are synonymous.

I don't want to vote because the question is too vague.
What do you mean by 'greener?' What is the source of electricity?

If human power is greener, what diet does the human eat and where is the food sourced?

It all comes down to far too simple questions to answer very complex issues.

Electric is greener, since it takes electricity to power the bike. And to recharge the battery, a power plant must burn fuel and give off CO2. Vegetation grows bigger with more CO2, so electric is greener.

Sounds silly, but so are people who believe that politicians are doing this to better the planet.

I vote for choice C, insignificant to the planet and focusing on the wrong global goal.

I was going to spend about a grand on a cheap bike and some batteries and a good hub motor for the front wheel.

Then, the more research I did, the more I realized what a pain in the butt it would be, dealing with burned out motors, batteries, charging, weight, etc.

I came to the conclusion that for a thousand dollars I could get a pretty darn nice bicycle. So I did. I spent 700 on a nice Trek Soho and then purchased some accessories like a helmet, riding outfits, lights, a rack, and a few more things.

I ride four miles each way to work, with some hills, and am loving it.

No electricity, no batteries, no worries, and my butt is getting firmer. My wife has noticed a difference in my body.

It's a no brainer.

anything around the 5 mile range is a great commute by regular human powered bike. You're very lucky to live so close to work, I on the other hand live 13.5 miles from work and there aren't any bike paths between me and work. Speed saves lives or at least i think so. I think I read somewhere that most Americans live within 15 miles of their jobs, im not sure what the spread is on that but, The human powered bike + the electric bike could dramatically change the world around us. Or we could all just sit around and argue about who's greener.

anything around the 5 mile range is a great commute by regular human powered bike. You're very lucky to live so close to work, I on the other hand live 13.5 miles from work and there aren't any bike paths between me and work. Speed saves lives or at least i think so. I think I read somewhere that most Americans live within 15 miles of their jobs, im not sure what the spread is on that but, The human powered bike + the electric bike could dramatically change the world around us. Or we could all just sit around and argue about who's greener.

I agree that bicycles could dramatically change our lives... except for one thing:


People want convenience. And they're willing to pay for it. They're willing to pay with their money and their health. But bikes.... especially electric bikes... will not work for one main reason. Commuting by bicycle is not convenient for the vast majority of us, and people WILL NOT pay money to be inconvenienced. And good quality electric bicycles with enough capacity to be really useful are VERY expensive.

I commute by regular bicycle 10 miles each way to work on an Air Force base with 16,000 people coming to work every day. And I pass another bike commuter about once every other week or so. It's not convenient to bicycle to work... so people won't even pay $400 for what we consider an entry level bike... do you honestly think that they'll drop that much or more on batteries alone? Great idea, but we're only talking each other into doing it here on the forums.

Your question is broad, which when broadly answered, neither is outright "greener". They both have ways you can go about it which are highly varying in their environmental impact.

You would need to do some serious data collecting and number crunching to figure out the averages, which the ebikes.ca article attempts to do nicely. Keep in mind that large, simple factors such as the type of diet of the rider, the source of the energy, and whether or not the battery is properly disposed of and/or recycled can tip the scales easily.

I'm more inconvenienced when I have to pay $70 to fill up my car. I save a full tank of gas every month just doing errands with the ebikes. That can make a $1000 ebike free pretty fast, especially if you can commute with it.

I'm more inconvenienced when I have to pay $70 to fill up my car. I save a full tank of gas every month just doing errands with the ebikes. That can make a $1000 ebike free pretty fast, especially if you can commute with it.

You totally missed the point of my post.

I have coworkers ask me all the time about how much I save in gas by riding. Even though they know that I save about $250 every month in gas I don't have to buy... they won't ride. They're willing to flush that money because it's too hard to ride... it's not convenient. If it's harder than jumping in and turning a key, they opt out. Hell... we have several motorcycle riders around here who won't even ride their motorcycles unless it's 75 degrees and sunny outside!

Here's about as green as I could find!

Get yourself a couple of batteries, charge them with this:
http://www.metacafe.com/watch/868499/free_hidden_electricity/

And then charge your bike from the batteries.

???? Beyond the moral aspects of it, I have verified with a friend of mine who is a line technician that it is around 52 volts DC, low amperage.

And where does the power from the phone company come from?

It's no greener than the power outlet in your wall.

Of course, stealing power is illegal. and stupid to steal from the phone. Who would be so stupid as to compromise an emergency system such as the phone system?
Again, they are both greener. This question is only relevent if electric bikes were the only alternative to a human only bike. Unfortunately, cars exist.

Here's my 2 cents. From a strickly greener point, human powered wins. But from the point of wanting and using a bike every day, rain or shine, or I feel tired this morning, gee that hill is getting steeper, then I found my electric bike wins, even with the small recharge power it takes. Before electrifying my bike, some days, minor excuses made me drive a vehicle.
Now I look forward to the ride every day. Not going to work, mind you, just the ride to get there!!

The problem with those claims that people eat more when using human powered is that they don't take into account that the typical American eats far more than what they need for their sedentary lifestyle. Which is why you see so many stories about people losing weight once they start riding a bike. If their consumption increased to offset their increased calorie needs, their weight would not drop.

The claim that electric bikes may be greener might be true when the subject is very calorie conscious and never eats in excess of the calories required.

I don't see why we need to focus on how much a rider eats.

I'm totally comfortable doing a comparison of how much energy is expended for an equal amount of work.

If I eat 10 carrots or 10 burgers, that is either a good idea or a bad idea.

If I ride a bike or ebike, which is greener?

don't confuse me with burgers and carrots! LOL

... Before electrifying my bike, some days, minor excuses made me drive a vehicle.
Now I look forward to the ride every day. Not going to work, mind you, just the ride to get there!!

Excellent point. Using an electric bike moves that "wimp out" point waaaaay up the scale!

My commute is 10 miles each way, and I do it currently on my Trek 520 complete with panniers, lights, bar bag, etc. It takes me about 6 or 7 minutes longer on my bike than in my car. With an electric assist bike, I could probably do it FASTER than in my car... or if I don't feel froggy that day, I can do it slower but with almost zero effort. It's too bad that the really nice bikes and kits are so expensive.

Of course, stealing power is illegal. and stupid to steal from the phone. Who would be so stupid as to compromise an emergency system such as the phone system?

Let me also point out (this was told to me by the electric company folks when i worked customer service there) that electrical wires are inherently dangerous, and you can only rely on fuses and circuit breakers when they're used in the kinds of situations they are designed for.

- if you use telephone connections for anything other than what they're designed for, you may trip a fuse or circuit breaker, and what's worse, you may NOT trip any fuse or breaker and instead just overheat some wires and cause a fire.

http://www.ebikes.ca/sustainability/Ebike_Energy.pdf <----- if you havent already seen it

That was a really interesting article. Not to mention the fact that it made me feel much better about my recent purchase of an E-bike kit with lithium-ion battery. :D

Electric is greener - folks who are turned off by the distance of their commute for human powered bikes are probably using cars instead. Electric bikes makes it easier for the average person to decide not to use cars at all, and IMHO this far outweighs any cost that electric bikes have on the power grid.

That's what guided my choice to go electric. Too far for me with my own two feet, but I hated using the car. I was thrilled to finally stumble upon the electric bicycle option. ...Of course, it would be greener if I just lived closer to work. :rolleyes:

One comment about stealing poer from your phone line: I've worked as an electronics repair technologist for a contract manufacturer that made Nortel telephones. If my telephony theory is good, I seem to remember that one of the phone lines is at about 80 volts, and when you pick up the handset from a phone, the phone places a load on the line...current starts flowing, and the voltage drops to 50Volts, and even less when there are 2 phones off the hook.
Anyways, the drop in voltage ( which is due to the current) is how traditional telephone companies determine that you are trying to place a call on your telephone.

So......if you try and steal power from the telephone line, you will be doing the same thing to the wire that the phone does when it is off the hook. So...YES, the phone company will know that something it up!

Also, I'm not sure if anyone can call you while you are stealing power.

Hell... we have several motorcycle riders around here who won't even ride their motorcycles unless it's 75 degrees and sunny outside!

We normally have about a dozen motorbikes parked where I work on the nice weather days. Any chance of rain, and I often arrive on my bike with not a single motorbike in sight. They are certainly fair-weather riders where I work. They seem amazed that I still ride. Of course, I enjoy the rain showers in the afternoon if they're not too heavy and without lots of lightning.


electric is greener...factor your food for fuel for your body...


It might be true that I eat a little more when I ride, but I honestly don't eat as many extra calories as I burn during the ride. That's why I now weigh 165 instead of the 225 lbs I used to weigh. Now I might buy your argument if you argue that now I'm going to live a lot longer because I'm a lot healthier, and that will obviously burn up some fossil fuel sometime in the future. :D

I read the article linked in this post, but I disagreed with some of the assumptions made in the premise for the article.

Electric bikes are definitely greener even if the power source is from coal. The only way regular bikes are greener is if you grow your own food and don't need to cook it that much.

1 Wh = 0.86 Cal. For a motor that's 80% efficient using a Li-Ion battery, 1 Wh used to charge the battery will output 0.8 Wh or 0.69 Cal of work to the wheel. For a human to output the same at 25% efficiency, they'd have to eat 0.69 * 4 = 2.76 Cal of food.

So in the end 1 Wh fed to a lithium-ion battery will replace 2.76 Cal of human food whenever you ride an electric bike. Do we release more C02 in producing a 276 Calorie plate of food than producing 100Wh of coal energy? I don't have the numbers for that, but knowing what goes into producing our food, I'm willing to bet that it does.

In electric bikes being greener, I'm not even factoring how riding an electric bike will motivate you to replace even more auto miles with bike miles.

1 Wh = 0.86 Cal. For a motor that's 80% efficient using a Li-Ion battery, 1 Wh used to charge the battery will output 0.8 Wh or 0.69 Cal of work to the wheel. For a human to output the same at 25% efficiency, they'd have to eat 0.69 * 4 = 2.76 Cal of food.


I'm an engineer, and I understand the math. I understand that both the energy to charge a battery and the food I eat can both be expressed in calories. But I cannot agree that battery charging calories, which come from energy made using coal or other energy sources can be directly compared with calories that are available to my body from food grown from the ground, which by it's natural growth process is converting CO2 to oxygen. You just can't compare these, even though they are both units of energy.

Now if you start comparing the energy required to produce and transport the extra food I eat from biking, then I'll hear some of that argument. But again, I disagree with most of the assumptions made at the beginning of the article in post #2.

I still contend that human cycling is greener. But I'm still listening to the discussion.

Now if you start comparing the energy required to produce and transport the extra food I eat from biking, then I'll hear some of that argument. But again, I disagree with most of the assumptions made at the beginning of the article posted in post #2.

I still contend that human cycling is greener. But I'm still listening to the discussion.

Please explain. I thought I read a comparison between calories used while biking vs. energy used in the production and use of electric-charged batteries. I'm not dissing ya. I just really want to understand your analysis, since the article made sense to me. What am I missing?

(Not that it matters in the grand scheme, since we will all choose a mode of transport that works best within our financial and physical means. ...But then we are back to the argument about the 10-15 miles commuters, who can choose electricty over gas-powered car.)

Please explain. I thought I read a comparison between calories used while biking vs. energy used in the production and use of electric-charged batteries. I'm not dissing ya. I just really want to understand your analysis, since the article made sense to me. What am I missing?


Assumption #1
"The first is that the electric bike and the conventional bike have similar energy
consumption per kilometre."

The article's author admits:
"It fails to be true if an individual travels faster on an electric bike than they
would under pedal alone, as air resistance adds considerably to the power
requirements."

I believe that the combination of extra weight in the ebike system along with the ability and urge to go as fast as possible make this a poor assumption. I believe that if you have an ebike system that adds 500 watts of power available to you, you will use most of it except on the downhills.

Assumption #2
"Only the consumables of both transportation modes will be considered in the
comparison."

So the author has left out the impact of production of the ebike components, though he points out that these are probably small effects.

Assumption #3
"This treatment is also ignoring all secondary effects. For instance, the health
benefits and costs of exercise will not be addressed, nor will the disposal of toxic
materials in batteries be considered."

Also ignoring the secondary effects of all that CO2 converted to oxygen by the plants growing to produce the food I eat, which is a positive effect to human powered cycling.

The article seems to assume that cyclists will eat enough calories to completely suplement all the energy they expend while riding their bike. I tracked my calorie intake for over six months when I started riding, since part of my reason for riding was to be in better shape and to lose weight. I dropped from 225 lbs to 165 lbs. Yes, I did consume more calories initially than if I didn't exercise at all, but my metabolism adjusted as I dropped weight. I now absolutely have to eat less than I was eating before in order to stay at my target weight. But the article gives me no credit for this, and assumes instead that I will eat as many more calories as I expend while cycling. Like I'm going to ride my bike and not reduce my weight or lower my body's metabolism.

Assumption #4 (later in the article)
"N human = 1:7 * 1:4 = 1:28

In other words, on average each unit of mechanical energy that a cyclist delivers
to the pedals comes at the expense of 28 units of primary energy (i.e. Fossil
fuels)."

I understand where these numbers come from, but I don't see an equivalent cost of delivering that energy to the battery charger in your home. I cost 7 calories of energy to deliver 1 calorie of food to my doorstep in the article, but what does it cost to deliver 1 calorie of energy to your battery charger. Is the energy cost of mining and transporting the coal and the energy consumed by it's production included? I may have missed this in the article, but I believe this is the main oversight in the articles calculations. They state a "grid efficiency" of 50%, but I do not believe that takes into account anything more than the conversion of coal at the power plant to electrical power. The cost to mine and transport that coal are not included in that number.

The article has a lot of good points, and it was eye-opening to read. But the analytical engineer side of me was taught to question and take apart assumptions, and to survey if all reasonable effects are included. I believe that if I had taken the same data and same amount of time writing such an article, I would have probably reached a different conclusion. That's all. :)

Well, my case is different.

on my power bill, I have the ability to allocate a portion of my energy needs towards purchasing wind power from the wind farms just south of my city.

I'm not sure of the rate, I am guessing it is 30% more than regular electricity. It would cost peanuts to allocate enough power so that my electric bike is effectively being run on wind power.


My bike uses about 1/2 Kilowatt hour per charge, and thats assuming a full discharge between charging. So even at double the cost, thats about 12 cents worth of power. multiply that by 20 working days = $2.40 cents per month. The other $2.40 cents of power for the trip home would come from my workplace. Something that my employer would be proud to do, he already owns a Honda Insight, so I think its a safe guess that he's ok with it.


In terms of money savings, I'd be saving most of the $14 per day that I spend on gasoline.

Hmm....considering that is $14 after taxes, in a weird sort of way, I'm actually getting paid about $26 before taxes to ride my bike for 2 hours per day. That hourly rate kinda sucks, but it still a novel idea.

Assumption #1
"The first is that the electric bike and the conventional bike have similar energy
consumption per kilometre."

The article's author admits:
"It fails to be true if an individual travels faster on an electric bike than they
would under pedal alone, as air resistance adds considerably to the power
requirements."

I believe that the combination of extra weight in the ebike system along with the ability and urge to go as fast as possible make this a poor assumption. I believe that if you have an ebike system that adds 500 watts of power available to you, you will use most of it except on the downhills.

Assumption #2
"Only the consumables of both transportation modes will be considered in the
comparison."

So the author has left out the impact of production of the ebike components, though he points out that these are probably small effects.

Assumption #3
"This treatment is also ignoring all secondary effects. For instance, the health
benefits and costs of exercise will not be addressed, nor will the disposal of toxic
materials in batteries be considered."

Also ignoring the secondary effects of all that CO2 converted to oxygen by the plants growing to produce the food I eat, which is a positive effect to human powered cycling.

The article seems to assume that cyclists will eat enough calories to completely suplement all the energy they expend while riding their bike. I tracked my calorie intake for over six months when I started riding, since part of my reason for riding was to be in better shape and to lose weight. I dropped from 225 lbs to 165 lbs. Yes, I did consume more calories initially than if I didn't exercise at all, but my metabolism adjusted as I dropped weight. I now absolutely have to eat less than I was eating before in order to stay at my target weight. But the article gives me no credit for this, and assumes instead that I will eat as many more calories as I expend while cycling. Like I'm going to ride my bike and not reduce my weight or lower my body's metabolism.

Assumption #4 (later in the article)
"N human = 1:7 * 1:4 = 1:28

In other words, on average each unit of mechanical energy that a cyclist delivers
to the pedals comes at the expense of 28 units of primary energy (i.e. Fossil
fuels)."

I understand where these numbers come from, but I don't see an equivalent cost of delivering that energy to the battery charger in your home. I cost 7 calories of energy to deliver 1 calorie of food to my doorstep in the article, but what does it cost to deliver 1 calorie of energy to your battery charger. Is the energy cost of mining and transporting the coal and the energy consumed by it's production included? I may have missed this in the article, but I believe this is the main oversight in the articles calculations. They state a "grid efficiency" of 50%, but I do not believe that takes into account anything more than the conversion of coal at the power plant to electrical power. The cost to mine and transport that coal are not included in that number.

The article has a lot of good points, and it was eye-opening to read. But the analytical engineer side of me was taught to question and take apart assumptions, and to survey if all reasonable effects are included. I believe that if I had taken the same data and same amount of time writing such an article, I would have probably reached a different conclusion. That's all. :)

Your argument on assumption # 1 makes sense to me, as I'm doing higher speed with the same energy expended. I go a lot faster with electrical assist.

On assumption #2, it seemed like production costs were taken into account.

Assumption #3) The study did not take into account recycling costs or costs of not recycling. I'm thinking that regardless of what we ride (car, bike, electric bike, etc.), we all need to be more conscious of the need to recycle. ...But, yes, the article left the costs a little unclear.

...You also make the argument (embedded within others) that we start burning more than we consume when we bike, so there is no increase in calorie intake. I would argue that this is also true with Ebikes. Many people brag about their weight loss after starting up on an Ebike. It might not be as significant as when riding on pure leg energy, but fewer calories are consumed than used. ...One personal side note is that the harder I ride, the more I crave meat, so my raw bicycling calories might have more environmental impact.

...Thank you for sharing your thoughts. I truly mean that. I agree that the energy consumption calculations are not simple, and many factors are at play. And I really wanted to know the scientific objections to the article.

It's also true, as other posters have pointed out, that an Ebike may provide a reasonable alternative for those who wouldn't ride a regular bike, therefore eliminating the use of one more car. I'm not sure what the stats are for that. I just know that without the Ebike alternative, I'd still be using car most of the time. I also know that my use of it plants a seed in the brains of those around me. ...Definitely, it's not measurable stuff, though.

It's also true, as other posters have pointed out, that an Ebike may provide a reasonable alternative for those who wouldn't ride a regular bike, therefore eliminating the use of one more car. I'm not sure what the stats are for that. I just know that without the Ebike alternative, I'd still be using car most of the time. I also know that my use of it plants a seed in the brains of those around me. ...Definitely, it's not measurable stuff, though.

I tipped the scales last friday at 400lbs. I have weightloss surgery scheduled for this month to deal with my overeating, and I would like to commute with my ebike to improve my level of activity. The doctors tell me that i'm looking at about a 2 year journey before I will be close to my target weight.

I'm confident that an ebike will reduce the work load, but increase the frequency on my workouts.

It's also true, as other posters have pointed out, that an Ebike may provide a reasonable alternative for those who wouldn't ride a regular bike, therefore eliminating the use of one more car.

Agreed. I am not opposed to an ebike, and would consider using one for commuting if I needed the assistance due to either health or hills or distance. I think it's an excellent alternative, and certainly may be more acceptable than a regular bike to the general population. Many of my friends have chosen motorbikes as an alternative to the car commute, while some have chosen either a scooter, and some a bicycle. I've seen ebikes in one of the shops here in town, but really don't have much knowledge of those yet. Almost anything is better than the one-person car commute, which I did previously.

I wonder if my wife would ride bikes with me if I got here an ebike to ride. She won't ride now, because she thinks I would either leave her or I wouldn't get to ride fast enough to enjoy my ride. :thumb:

I wonder if my wife would ride bikes with me if I got here an ebike to ride. She won't ride now, because she thinks I would either leave her or I wouldn't get to ride fast enough to enjoy my ride. :thumb:


That's how I got my wife on the road. At one point I thought she would never get on a bike by herself so I even considered getting an xtracycle with seat or something so she can get on with me. I just bought her an ebike and once she tried, she was hooked. We do all of our errands with them. ;)

I'm an engineer, and I understand the math. I understand that both the energy to charge a battery and the food I eat can both be expressed in calories. But I cannot agree that battery charging calories, which come from energy made using coal or other energy sources can be directly compared with calories that are available to my body from food grown from the ground, which by it's natural growth process is converting CO2 to oxygen. You just can't compare these, even though they are both units of energy.

<b>Now if you start comparing the energy required to produce and transport the extra food I eat from biking, then I'll hear some of that argument.</b> But again, I disagree with most of the assumptions made at the beginning of the article in post #2.

I still contend that human cycling is greener. But I'm still listening to the discussion.

That's exactly what I'm talking about. The energy it takes to produce the food in our modern food production system takes a lot of energy -- fertilizing, processing, transporting, freezing, preparing, etc...

Yes, the food itself is not taxing on the environment at all. It's just recycled CO2 from the existing air (whereas coal is new CO2 taken from the ground and burned into the air). If you grow all your own food, you can probably say that human power alone is greener than a human electric hybrid.

Assumption #1
"The first is that the electric bike and the conventional bike have similar energy
consumption per kilometre."

The article's author admits:
"It fails to be true if an individual travels faster on an electric bike than they
would under pedal alone, as air resistance adds considerably to the power
requirements."

I believe that the combination of extra weight in the ebike system along with the ability and urge to go as fast as possible make this a poor assumption. I believe that if you have an ebike system that adds 500 watts of power available to you, you will use most of it except on the downhills.

Most e-bikers go from 14 mph to around 18 mph. There's not a lot of wind resistance difference between those speeds. I'd agree there's a significant energy required to go from 18 to 22 mph though.

But the point is that a hybrid human electric bike is better for the environment at any speed than human power alone at the same speeds. If a car was as environmentally friendly as a bicycle was at low speeds, there'd be much less need for a bicycle as an environmentally friendly option. It would be up to you to decide how fast to go taking into account that the faster you go, the more CO2 you output.



Also ignoring the secondary effects of all that CO2 converted to oxygen by the plants growing to produce the food I eat, which is a positive effect to human powered cycling.

Unless you eat the food right out of the garden, this statement isn't true. The more food you grow, the more coal and oil our system uses to get it to our kitchens.




The article seems to assume that cyclists will eat enough calories to completely suplement all the energy they expend while riding their bike. I tracked my calorie intake for over six months when I started riding, since part of my reason for riding was to be in better shape and to lose weight. I dropped from 225 lbs to 165 lbs. Yes, I did consume more calories initially than if I didn't exercise at all, but my metabolism adjusted as I dropped weight. I now absolutely have to eat less than I was eating before in order to stay at my target weight. But the article gives me no credit for this, and assumes instead that I will eat as many more calories as I expend while cycling. Like I'm going to ride my bike and not reduce my weight or lower my body's metabolism.

An electric bike will also allow you reach your target weight or lower your metabolism as well... perhaps it'll take a little longer if you ride the same distance.

Once you reach 165 or any target weight, my argument is that you'll need even less food to maintain that weight if you were riding an electric bike over the same distance rather than a conventional bike.



I understand where these numbers come from, but I don't see an equivalent cost of delivering that energy to the battery charger in your home. I cost 7 calories of energy to deliver 1 calorie of food to my doorstep in the article, but what does it cost to deliver 1 calorie of energy to your battery charger. Is the energy cost of mining and transporting the coal and the energy consumed by it's production included? I may have missed this in the article, but I believe this is the main oversight in the articles calculations. They state a "grid efficiency" of 50%, but I do not believe that takes into account anything more than the conversion of coal at the power plant to electrical power. The cost to mine and transport that coal are not included in that number.

The cost of mining and transporting the coal to produce electricity for the electric bike battery still exists for the electricity used in processing, storing and preparing our food. And IMHO, you need more electricity to produce 276 kCal of food than 100 Wh of electricity.

And don't forget all the gas and oil we burn to get the food to your kitchen.

Occasionally, I need to travel 30 miles by conventional bike. On those days I do, I definitely drink more energy-like drinks and eat more snacks and eat more food than I do on electric bike days going 30 miles.