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Car sharing economic impact is significant yet unrecognized. A formal economic analysis could help raise awareness among public officials.



As the founding CTO of Zipcar I have always believed that the economic impact of car sharing is huge and goes unrecognized.  While I am no longer affiliated with Zipcar that hasn't changed my opinion about the impact.

First, there is the fact that 40% of the members report that they have sold their car or avoided purchase of a car.  So far few cars are owned by Zipcar members than non-Zipcar members.  In Cambridge, for example, this has resulted in 3000 - 4000 fewer cars registered in the city.  

Car sharing members drive less.  Because they pay incrementally for the fully loaded cost of a car, they make rational choices about alternatives for a particular trip.  They walk, bike, use public transit, combine a trip with other trips, travel with a friend, etc.  This results in much lower VMT, lower emissions, etc.

Indirectly this also reduces the demand for parking.  I believe that both MIT and Harvard, for example, have avoided the construction of an entire parking garage due to the reduced demand for parking on their campuses.  The same is true across the country in cities with health car sharing business.

Car sharing members spend less on their car.  Since they make the decision to buy on a per trip basis, car sharing members spend much less per year on transportation.  While the average car owner spends $9,122 per year on their car, the average Zipcar member spends less than 1/10th of that.  

I believe that this results in car sharing members having, on average, several thousand dollars of additional disposable income annually.  And I believe that much if not most of this is spent locally. Compared to money spent on a personal car which mostly leaves the local community (e.g. initial car purchase, fuel, some maintenance costs, financing).

I think there are other positive impacts on the local environment and economy - the opportunities created by access to on-demand transportation for example.

All of htis begs for a serious economic analysis of the impact of car sharing.

Category of the action

Building efficiency: Physical Action

What actions do you propose?

An economic analsys of car sharing.  Exactly what does this entail?  I'm not sure, as I am not an economist.  But I'm sure there are some clever economists out there who would be happy to describe what could be done.

Who will take these actions?

some economists.  How about a PhD thesis, anyone?

Where will these actions be taken?

This would result in publication of results at the least, and help to influence policy makers, politicians, and bureaucrats, by giving them strong evidence to support their actions in support of car sharing as a way to make their cities more livable and improve the lives of all of their citizens.  All the while, reducing carbon emissions and other pollution from much reduced VMT and improving the economic well-being of their citizens at the same time.

How much will emissions be reduced or sequestered vs. business as usual levels?

There is at least a 50% reduction in emissions (documented in reference below), however I believe that the reduction is much higher, probably more like 90%.  In other words, the total emissions from cars that would have been driven by car sharing members is 10x the emissions from the fleet of car sharing vehicles.  Simple math with Zipcar's 850,000 members whose driving needs are met with a fleet of only 10,000 cars shows this.

What are other key benefits?

I think the primary benefit will derive from recognition of the impact of car sharing.

What are the proposal’s costs?

I estimate the cost of a serious economic analysis to be $50K - $100K.

Time line

6 months

Related proposals


AAA report what to Americans spend on their personally owned vehicles?

car sharing impact report: