How much carbon does bike-sharing save?

By Felix Salmon
December 2, 2010
CityRyde has a bright idea: why not sell carbon offsets?

" data-share-img="" data-share="twitter,facebook,linkedin,reddit,google" data-share-count="true">

How should bike-share services pay for themselves? Up until now, the main model has been sponsorship and advertising. But CityRyde has a bright idea: why not sell carbon offsets?

The idea’s pretty simple: as bike-share use rises, the amount of carbon-emitting vehicle use falls. So bike shares save carbon; CityRyde even has a methodology to determine exactly how much. (One thing I’d like to see, though: virtually all bike-share programs involve trucking bikes from the center of town back into the periphery, not to mention transporting broken bikes to be fixed. So somewhere in the methodology there should be an accounting for the amount of carbon emitted by the bike-share program itself.)

In any case, if the bike-share program sold carbon offsets to companies which want to claim to be carbon-neutral and to individuals wanting to offset their carbon emissions, that could raise some revenue: CityRyde co-founder Jason Meinzer told me his rule of thumb is that you could bring in between $25 and $100 per bike per year that way. For a scheme with 50,000 bikes in New York City, that would equate to between $1.25 million and $5 million per year: hardly chump change.

Meinzer didn’t share with me exactly how he got his numbers, though, so I ran a smell test. Let’s say each bike travels 15 miles per day, 350 days per year: that’s 5,250 miles per year. A lot of bike rides are simply for pleasure, and others—especially in a city like New York—replace walking or taking mass transport. Those are activities with negligible marginal carbon emissions.

But let’s say that 1/3 of bike journeys would otherwise have been taken in a car of some description. That means that each bike saves 1,750 passenger-miles in cars. If one car carries the same number of people as two bikes, on average, then that’s 875 car miles saved. At 1.2 pounds of CO2 per mile, that’s basically half a ton of CO2 emissions saved per bike per year. And while the market in carbon offsets is far from transparent, my feeling is that you’d be lucky to get $5 per ton, which would equate to $2.50 per bike per year. That’s a full order of magnitude lower than Meinzer’s lower estimate.

Meinzer’s methodology is a lot more sophisticated than that, and I’ll update this post if he wants to share his own math. But at $5 per ton, selling carbon offsets would gross only about $125,000 a year—which, by the time you subtract the cost of measuring the carbon saved and administering the sales, leaves you with little or nothing in net revenue. So while it’s an intriguing idea, I’m not yet convinced it’s a practical one.

Update: Meinzer says that he does account for the carbon costs of the program, in the “Project Emissions” and “Leakage” sections of his methodology; I don’t see it myself. And he explains that he gets his much higher estimate for total revenues from selling carbon offsets at a much higher price:

Our credits most certainly will be sold at a premium due to the novel co-benefits associated with their generation even outside of the carbon mitigated; e.g. health and social (and remember some credits sold for as high as $111 last year). This has been validated by the carbon brokers we’ve been working with over the years. Moreover, outside of the “price-point” per carbon a key angle we are taking to obtain an even higher premium on our credits is via creative bundling; by lumping the carbon credits w/ the sponsorship and advertising. Case in point – Blue Cross Blue Shield donated $1.5 million to have their name tied to the existing 1,000-bike Minneapolisbike share. Had they been able to purchase the offsets stemming from that program the donation would have been MUCH higher. This argument is reinforced by the fact that this donor in particular clearly has a key interest in health, and so the aforementioned co-benefits of our credits would prove even more attractive given the health-benefits of biking. Most big names companies are already offsetting their carbon emissions each year anyways for a variety of reasons, even outside of a regulatory mandate.


We welcome comments that advance the story through relevant opinion, anecdotes, links and data. If you see a comment that you believe is irrelevant or inappropriate, you can flag it to our editors by using the report abuse links. Views expressed in the comments do not represent those of Reuters. For more information on our comment policy, see

What a complicated solution. This post illustrates to me why carbon offsets are unlikely to do much. If you want to reduce emissions, you need to make carbon emissions more expensive, instead of handing out credits for certain fairly arbitrarily defined forms of “good behavior”. If I read a book, should I get a carbon offset subsidy? After all, I could be skydiving instead, so I am definitely saving carbon by reading, and also sequestering carbon from dead trees in my bookshelves. Or should we restrict book subsidies to former skydivers?

Carbon offsets seem arbitrary and uncheckable and easily gamed. I am afraid the main impact of such offsets is to make people feel better about themselves while the climate goes to hell.

Posted by TSTS | Report as abusive

Sadly, this doesn’t work at all.

For the carbon emitted by someone cycling themselves is higher than the carbon emitted from gasoline used to transport said people.

The problem is that human beings are really very very inefficient consumers of energy: and we get our energy from a very inefficient process known as agriculture.

Posted by TimWorstall | Report as abusive

“… the carbon emitted by someone cycling themselves is higher …”

Exactly! That’s why societies with higher bicycle usage must consume much more fossil fuel per capita, in order to support their wasteful, bike-riding habits. Oh wait, they don’t.

The study on which this fanciful proposition is based was debunked the moment it was published. But since it provides a convenient rationalization for being fat and lazy, its appeal will never fade.

Posted by Greycap | Report as abusive

CityRyde is going to sell carbon offsets to generate revenue for its business eh? That is the most diabolically brilliant scheme I have heard of yet. Carbon offsets as the concept appears to me are totally arbitrary, made up devices for a way to solve a problem nobody is really sure of how to actually solve (or even if it exists) and hold no real value whatsoever. CityRyde is going to take these valueless, made up devices and “sell” them for real funds to generate revenue for its company. And not to make donations or further research for “green” technology (no where on its website does it state that is what it wants to do) but to simply cover costs and turn a profit as any private business strives to do. Who can claim that that is not absolutely genious? Ya know, I am going to go buy a Prius, feel good that I am doing my part to be “green”, then “sell” carbon offsets to those who still drive Hummers so I can pay off the car loan. Thanks for the idea CityRyde!

Posted by iflydaplanes | Report as abusive

“For the carbon emitted by someone cycling themselves is higher than the carbon emitted from gasoline used to transport said people.”

What complete, utter nonsense.

Posted by Mike.Gayner | Report as abusive

While I agree carbon emissions should be decreased, I do not agree increasing the cost of them is fair.
7 months of the year, bikes…electric cars..walking are impossible where I live. I suppose if we all lived in Arizona it would be a great idea. Many of us live in cold climates and have to rely on fuels to survive.
I hate the fact I have to pay for a gas guzzler and heating bills that compare to some peoples rent, but the die is cast for my life and moving is not the answer.
I suppose we could all return to riding horses for transportation or just stay home on the couch until our solar panel power failed for our XBoxes.

Posted by ChillyWillie | Report as abusive

So they expect $111 or more per ton. Yet before it shut down for lack of interest, the Chicago Climate Exchange (which was the only legally binding greenhouse gas (GHG) reduction and trading system for emission sources and offset projects in North America) had a metric ton of carbon listed at between 5 and 10 cents, That is over 1000 times less than CityRyde is projecting.

Posted by ddpalmer | Report as abusive

Perhaps the bike-share companies could improve their green credentials by incorporating this kind of technology on their equipment:

(aka, Felix, meet your iPhone!)

Posted by politicalcalcs | Report as abusive

“For the carbon emitted by someone cycling themselves is higher than the carbon emitted from gasoline used to transport said people.”

But people also emit carbon while driving …

Posted by DaveKrentz | Report as abusive

A nice calculator for bike vs car travel emissions is here: gy.html

In any case, firstly, organisms are quite efficient at energy production compared to machines. Second, bicycling is a very efficient mode of transport even among human-powered modes. Third, can you really believe that moving a ton or two of steel around with you in it is more efficient than moving yourself with 20 pounds of bike?

Posted by AardvarkGumbo | Report as abusive

To the guy who said “CityRyde is going to sell carbon offsets to generate revenue for its business eh?” — No.

CityRyde is going to sell the methodology to generate carbon offsets to sustainable transportation initiatives in order to help them generate revenue to support the construction of sustainable infrastructure. As someone who’s actually followed the company, I can tell you that generating funding for green transportation is precisely what they’re trying to do.

Posted by istealllamas | Report as abusive