Peer-to-peer car sharing (sometimes called distributed, neighbor-to-neighbor and car sharing 2.0) facilitates car renting between personal car owners and a network of interested renters. In contrast, for standard car sharing from ZipCar or CityCarShare, the organization owns the fleet of cars.

Probably even more companies will launch P2P car sharing services in the coming months, with new ways to target already-existing communities, and eventually the market will face consolidation. But in the meantime, here’s my cheat sheet of a dozen companies offering websites to facilitate peer-to-peer car sharing among neighbors.

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Think of the strategy as similar to the way that Facebook was able to create trusted social networks at colleges before it spread elsewhere. And interestingly enough, Facebook early-exec-turned-investor Chamath Palihapitiya was the lead seed investor in the company, and other angel investors include Jim Freer, Sebastien de Halleux, Felicis Ventures and Red Swan Ventures. Wheelz, which has been under development since early 2011, has raised $2 million.

Peer-to-peer car sharing is a new model of car sharing where car owners rent out their cars by the minute or hour to other users in the network. Drivers can use mobile apps to unlock the cars and the web to reserve cars in nearby locations. In contrast, traditional car sharing companies like Zipcar and CityCarShare own and maintain the car fleets themselves, which can get pretty expensive. Traditional car sharing companies have struggled to be profitable because of the high cost of car ownership and maintenance.

The concept of P2P car sharing is compelling enough that there’s a handful of startups out there building networks, including Getaround, RelayRides, Spride Share and WhipCar, in the U.K. RelayRides is backed by Google Ventures and August Capital. Getaround has raised money from TechCrunch creator Michael Arrington‘s CrunchFund, Redpoint Ventures, General Catalyst and a group of angel investors including Netflix founder Marc Randolph and WordPress founder Matt Mullenweg (see disclosure). Spride Share is backed by Spring Ventures founder Sunil Paul and has an advisory board that includes LinkedIn founder and chairman Reid Hoffman, Zynga CEO Mark Pincus, UC Berkeley Institute of Transportation Studies director Dan Kammen and City CarShare CEO Rick Hutchinson.

For now, the amount of people actually using these peer-to-peer car sharing networks is so small that there’s room for a bunch of them. It’s likely that they will each grow in certain niches, neighborhoods and cities and perhaps down the road will merge or get bought by the traditional car sharing companies. The technology won’t be the differentiator — a mobile app and an unlocking mechanism can be pretty basic and commoditized. It will be marketing, market focus and business model that determine which of these companies draws in more customers.

That’s one reason why Wheelz is a potential player, despite that it’s entering the market later than the others. Carpooling company Zimrides took the same approach to focus on already-created trust groups at schools and businesses as their core market first and then only later moved to make its service more open to the public. As the security issues with Airbnb have shown, trust will be a major part of the web sharing economy, and companies that understand that early on will benefit.

Disclosure: Automattic, the maker of WordPress.com, is backed by True Ventures, a venture capital firm that is an investor in the parent company of this blog, Giga Omni Media. Om Malik, the founder of Giga Omni Media, is also a venture partner at True.

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Katie takes a look at this fast growing space in an analysis on GigaOM Pro, where she writes:

The ubiquity of the Internet itself and its unique ability to be able to connect people and help them organize goods and their daily lives has led to the rise of the web-sharing economy, which some call collaborative consumption and others call the Mesh. Older Internet pioneers like eBay and Amazon have paved the way for this movement by creating tools to maintain online trust and reputation — a key element of this movement. Feeling comfortable with allowing people in your neighborhood to share your car (like with RelayRides, Spride Share and Getaround) is a crucial part of the web-sharing economy.

While there’s no doubt that web-sharing is generating excitement, it’s also seen some growing pains, as evidenced by recent news about abuse and misuse by those using the service.

Here at GigaOM, we want to hear what our early-adopter audience thinks about this emerging opportunity. Take a few minutes to fill out our survey, and we will email you an executive summary of the results. You’ll also have a chance to win one of three free GigaOM Pro annual subscriptions or a free ticket to a GigaOM Pro event of your choice.

UPDATE: The survey has been closed. Keep an eye out for results soon!

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• How to leverage the web-sharing economy now
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• Cleantech, meet connectivity: a new era of energy efficiency

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As I put it in this piece, the year of the car as a service has finally arrived. One small hiccup for Zipcar: It’s not profitable, and likely won’t be profitable this year. For the year ended December 31, 2010, Zipcar generated revenue of $186.10 million, with a net loss of $14.12 million. As of December 31, 2010, Zipcar had an accumulated deficit of $65.4 million, and in the company’s risk factors in its S1, it says, “We expect to incur a net loss in 2011. We do not know if our business operations will become profitable or if we will continue to incur net losses in 2012 and beyond.”

Car sharing is an expensive business when you have to own and maintain the cars in the fleet. As of September 2010 (when I did this analysis), Zipcar had 8,541 cars in its fleet, most of which it leased, but 1,692 of which it owned outright. Most of Zipcar’s costs are maintaining cars, and buying and selling the cars, which it only keeps on an average of two to three years before it sells them to the used-car market.

A less capital-intensive version of car sharing is neighbor-to-neighbor car sharing, which is being promoted by startups like RelayRides and Spride Share. (Hear from these companies at Green:Net 2011, on April 21 in San Francisco.) In this next-gen car sharing world, the members of the community own the cars and rent them out to their neighbors.

Zipcar needs the $174.24 million to expand its fleet and bring in more users; there are only 560,000 members after eleven years in business. But, according to Frost & Sullivan, the revenue from car sharing programs in North America will increase to $3.3 billion in 2016, up from $253 million in 2009.

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Getaround, along with a spate of competitors including RelayRides in San Francisco and Boston, SprideShare in San Francisco, WhipCar in the UK, and CityzenCar in France, fits into the larger trend of using the web to help people share “stuff.”

How to Get Around

Here’s how it’s supposed to work: To sign up as a driver in Getaround’s Beta launch, you enter some basic information on Getaround.com, including date of birth, gender, zip code, and whether you know how to drive a stick shift. To complete the signup, you log in to Getaround using your Facebook account, granting it access to some of your Facebook data. Before you can rent a car, Getaround also checks your driving record.

For the car owner, Getaround seeks to provide “a lot of flexibility and control” over who can rent the vehicle and how. “You can choose to share with one or two people, or the whole neighborhood,” said Jessica Scorpio, co-founder and business development chief for Getaround. “We’re the marketplace to make it happen.”

The owner of a Tesla Roadster Sport in the program, for example, only considers requests from drivers who are at least 30 years old, and she requires a minimum 2-hour rental period (at $25 per hour). Drivers can “bundle” requests for up to five cars for a given rental period, and then the car owner who responds first wins the gig. Owners set the rental rate, and Getaround takes a 30 percent cut of each transaction.

Requiring users to have a Facebook profile helps Getaround verify identity, said Scorpio, and also encourages good behavior. “If drivers know you have access to their real Facebook profile,” she said, “they’ll be more cautious.” Down the road, Getaround plans to integrate more closely with Facebook, enabling users to rent their vehicle only to existing network connections, for example.

Once a driver and owner have agreed to a rental, Getaround generates an email confirmation that will allow the driver to locate, honk, unlock the car using a smart phone, thanks to the “Carkit” device that owners can have installed on their vehicle for $200. Currently Getaround offers an app for the iPhone and it plans to release an Android app in the near future, but the browser on a smart phone can also do the job, according to Scorpio. Car owners who prefer to meet the renter and hand over keys in person can skip or delay the hardware installation.

Getaround accepts only vehicles from the 2000 model year or later with no more than 100,000 miles on the odometer, and the company hopes to recruit a large number of “green vehicles,” including more all-electric models. Scorpio said Getaround currently has 60 cars active throughout California, mainly in the San Francisco Bay Area and San Diego, where the University of California has provided funding for a small-scale trial project. At least 40 additional vehicles are moving through Getaround’s approval process. In all, Scorpio said “a few thousand” people have signed up to use Getaround.

While the 12-person company is focusing most of its efforts on proving its model in San Francisco, said Scorpio, Getaround can support peer-to-peer car sharing anywhere in California. Next year the ambitious startup hopes to expand across the country, and within five years it aims to go global.

Peer to Peer Car Sharing

It’s not mere coincidence that distributed car sharing services are sprouting up in California. In September legislation called AB 1871 passed in the state that paves the way for distributed or “peer-to-peer” car sharing programs. The legislation established rules for when a vehicle owner’s insurance policy stops applying, and when a commercial policy held by a service provider like Getaround kicks in.

Getaround “did as much as we could” to encourage passage of AB 1871, said Scorpio. But the company’s origins trace back to a 2009 group project at Singularity University’s 10-week, $25,000 summer program in Mountain View, Calif. Created by futurist Ray Kurzweil and X Prize chairman and CEO Peter Diamandis, Singularity University’s courses and programs focus on “exponentially growing technologies in order to address humanity’s grand challenges.”

The group’s concept for an iPhone app that facilitates “peer-to-peer” car-sharing won the “best money making app” category in a hackathon competition at Yahoo headquarters in July 2009. By September three of the team members — Scorpio, plus Sam Zaid and Director of Engineering Elliot Kroo — had officially founded the startup now known as Getaround.

Given its Silicon Valley roots, it’s no surprise that Getaround considers itself a technology company. But at the end of the day, Getaround’s success and growth will depend as much, if not more, on the company’s handling of low-tech issues like auto insurance, legislation and customer service. Streamlining the hardware aspect will be crucial for the company to achieve its vision of a global footprint.

As Spride Share co-founder Sunil Paul put it in an interview, Spride’s distributed car-sharing platform (which unlike Getaround, requires a key fob for entry) offers an example of a greentech venture that’s enabled by technology, yet fundamentally is not a technology play. “This is not going to be the whiz bang app, or the whiz bang anything,” he said. Rather, Spride’s success will hinge on catching policies up with an opportunity and capitalizing on what Paul sees as a general trend toward cars in “reasonably dense settings” becoming a shared resource.

Mobile Phone Tech As Enabler

During a rental session, Getaround tracks location data via users’ smart phones as well as the so-called Carkit installed on each vehicle. The company allows vehicle owners to set when and where other Getaround users can view the location of their car when it’s parked. And according to the company’s privacy terms, the vehicle owners also “may be able to see the location” of their car during the rental period. “Other than that,” says Getaround, “other users will not be able to see your movements….unless you choose to enable ride-sharing features.”

Might Getaround partner at some point with a smartphone-based ride-share service, such as Zimride, Carticipate, Avego or Daimler’s Car2gether? According to Scorpio, the company is interested in partnering with car sharing companies, municipal transportation departments, universities, and “P2P companies,” which she described as “anything that helps you share assets.”

According to Scorpio, Getaround does not actively monitor driving information in real time. Rather, she said the company is more interested in patterns (for example, if you speed during every rental session) and being able to track down a stolen vehicle. “We want to know if it’s going 100 miles an hour toward Mexico,” she explained.

Getaround has built a device called a Carkit that allows this data collection, and also makes keyless entry using the company’s iPhone app possible. The device, according to Scorpio, is “as non-invasive as it can get,” plugging in “very easily” to a car’s ODB-II (on-board diagnostics) port. Currently Getaround picks up vehicles from new members and brings them to professional mechanics for the Carkit installation. This is a clunky, costly step for a startup trying to build a web-based global service, so Getaround is working to simplify the process and hardware.

Scorpio expects 2011 to be a big year for the company. Getaround has raised seed funding from Redpoint Ventures and Powerset founder Barney Pell. The startup not hurting for cash at the moment, said Scorpio, but it plans to seek Series A financing this year.

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Widespread access to so-called “mobility as a service,” is a crucial piece of this greener transportation puzzle, making it easier for us to go car-free more frequently. Over the course of 2010, a rich ecosystem of services, startups and innovations began to take shape.

As envisioned by MIT researchers, a fully fleshed-out Mobility on Demand system would involve a comprehensive network of services in which city residents could rent an electric car, scooter or bicycle when and where they need it in order to bridge the “last mile” gap between public transit stations and a final destination.

The effects of sharing bikes and vehicles could extend well beyond the transportation sector. According to a report out this fall from research firm Latitude, car-sharing is kindof like a gateway drug for the growing trend of using the web to help people share physical things. People who try out car-sharing services are more likely to join in other web-based sharing services, and folks who share vehicles share significantly more than non-car-sharers across a range of categories, from living space to food to media. Here’s seven steps taken this year toward shared transportation.

Bike Sharing Boom: Bike sharing networks, in which city residents or tourists can rent bicycles by the hour or day, have been around for years. Paris, with the Velib program it launched back in 2007, helped popularize the idea, but it wasn’t until this year that bike sharing — often enabled by mobile access to the web and GPS — began to gain momentum stateside. Programs launched in Denver, Minneapolis, Washington, D.C., and other metro areas.

New York City is up next, as the Big Apple’s transportation department requested proposals last month to set up a high-tech system for borrowing or renting bikes for short trips, starting around the spring of 2012. Across the pond, London launched a program called Barclays Cycle Hire in July and by November it was set for expansion, having already logged more than 1.5 million journeys and signed up over 100,000 users.

Green Light for AB 1871: In September legislation called AB 1871 passed in California that paves the way for distributed or “peer-to-peer” car sharing programs, which let car owners rent out their personal vehicles. The legislation establishes rules (going into effect January 1, 2011) for when a vehicle owner’s insurance policy stops applying, and when a commercial policy held by a service provider like RelayRides or Spride Share would kick in.

Distributed Car Sharing Revs Up: Following passage of AB 1871, startups including Spride Share, RelayRides and Get Around (which started as a team project at Peter Diamandis and Ray Kurzweil’s Singularity University in Mountain View) have launched services to facilitate distributed car sharing. Big-name investors have put some skin in the game, too. Having launched in the Boston area in the fall, RelayRides expanded to San Francisco this month, and announced its first round of investment from Google Ventures and August Capital.

Zipcar Guns for IPO: The car sharing market fielded its first IPO registrant this year, with Zipcar filing in June to raise up to $75 million in a public offering. Plans for proceeds from the offering include, among other things, repaying more than $40 million in debt, developing new services, expanding its fleet and paying some $5 million to shareholders in the recently acquired Streetcar. Then again, the company raised a $21 million Series G financing round earlier this month, which could mean the IPO is on the rocks.

Streetcar Acquisition: In its latest bid to expand across Europe, car sharing heavyweight Zipcar bought London-based car-sharing firm Streetcar this spring in a deal valued at about $62 million. Zipcar CEO Scott Griffith called the deal (which came on the heels of an investment in Spanish car-sharing startup Avancar late last year) a key step toward making the company a “truly global” car-sharing network.

UK antitrust authorities halted integration of the two companies while they looked into whether “the transaction may result in a substantial lessening of competition in any relevant market in the United Kingdom,” but ultimately approved the transaction this week.

Big Auto Starts Sharing: With the launch of a pilot project that will let customers rent any current BMW model by the hour from the company’s event center in Munich, BMW Group broke into car sharing this fall. It wasn’t the only example of a big auto company moving into Zipcar’s turf in 2010. Daimler expanded its two-way city car sharing program Car2Go (pick up a Smart Fortwo in the Car2Go fleet, drop it off at any open parking spot in the program area).

Daimler also launched the Twitter of ridesharing, Car2Gether, which identifies and links passengers and drivers with empty seats that are nearby and heading in the same direction. What’s a German car company doing getting into social networking and tech-enabled carpooling? Trying to figure out new business models for an era of accelerating urbanization, declining car ownership and expanding access to the mobile web.

Hertz Snaps Up Flexicar: In October, rental car giant Hertz announced an agreement to acquire Australia’s largest car sharing provider, Flexicar. Already making inroads with car sharing in Berlin, London, Madrid, New York and Paris, Hertz added Melbourne and Sydney to its Connect by Hertz footprint with this deal. The companies planned to integrate Flexicar’s 2,500 members into Connect by Hertz shortly after closing the deal (expected this month).

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Founded in 2009, RelayRides began offering what founder and CEO Shelby Clark calls “neighbor to neighbor” car sharing in the Boston area in September. The concept is like “cloud computing for cars,” as Sunil Paul, CEO of competitor Spride Share, has put it to us. With cloud computing, users can share computing infrastructure over the Internet, accessing software, data and other resources on demand. With transportation and car sharing, the idea is to provide mobility as a service. At a basic level, rather than buying a car, you could buy access to a car whenever you need it.

Piggybacking on the idea of popular car sharing services like Zipcar, RelayRides “makes it easier to live without a car,” said Clark, and can lead to “stronger communities.” Collecting feedback from users in Boston, RelayRides has learned that people on both sides of the car share equation — vehicle lenders and borrowers — “feel like they’re helping each other,” either by providing some extra income through the rental fee or by providing wheels when they’re needed. Car owners set their own hourly rate and get 65 percent of the fee, while RelayRides takes a 15 percent cut. The remaining 20 percent goes toward insurance.

RelayRides is still solidifying its deal with Google Ventures and August Capital, and the startup tells us that the amount of investment should be disclosed in the next few days. RelayRides has previously raised $500,000 in angel investment, and Clark said it has already received some funds from Google Ventures. He declined to comment on questions about profitability.

Starting on Tuesday, “a handful of vehicles” will be available in the San Francisco fleet. Car owners in San Francisco can enroll on the company’s website, prompting a call from RelayRides to answer any questions. From there, the car owner can schedule installation of some hardware, which enables communication with RelayRides’ servers and controls access, so only a user with a current reservation can unlock and start the vehicle.

Vehicles enrolled in the Boston RelayRides fleet have a keypad interface that lets drivers extend a reservation, but Clark said the San Francisco fleet will feature an upgraded, more streamlined system without the in-vehicle interface.

Cutting the installation time to 1 hour, from 3-4 hours with the older system, the hardware changes could be a smart cost-cutting move for the company if it’s looking to expand to more markets. According to Clark, the company aims to serve not only cities but also areas with lower population densities — the suburbs and “urban fringe” — where traditional car sharing providers can’t profitably operate. Without the cost of owning and managing its own vehicle fleet, said Clark, RelayRides can afford to have more down time, or lower utilization rates for each vehicle.

For security, a RelayRides vehicle’s ignition will be immobilized except for access by the car owner or an authorized borrower. General vehicle locations can be viewed without a reservation, but users only find out the exact address via text message once the rental is finalized. RelayRides also emails the user a map at that point marking the vehicle location (each enrolled vehicle is outfitted with a GPS system for finding the vehicle and tracking mileage ). As Clark put it, since the keys are kept in the car and its location is being advertised, it would be “asking to be stolen” without these precautions.

Also on Tuesday, RelayRides will begin screening drivers who sign up on the company’s website (the company checks for a history of violations or tickets). Once approved for membership, drivers can reserve vehicles through RelayRides’ website and unlock a car during their time slot with a smart card. Next month, users will also be able to register San Francisco’s Clipper transit pass for this purpose, with RelayRides reading a digital signature on the card and assigning it to a particular user, said Clark.

For companies like RelayRides and Spride Share, insurance is one of the biggest bugaboos. Until recently, insurance regulations in California and other states allowed insurance companies to void a vehicle owner’s insurance policy if the car was rented out to others.

In September, however, legislation called AB 1871 passed in California that establishes rules for when a vehicle owner’s insurance policy stops applying, and when a commercial policy held by a service provider like RelayRides would kick in. RelayRides holds a $1 million supplemental insurance policy that goes into effect during each reservation period.

Clark believes the legislation “forced a lot of people to take a position on personal car sharing.” By clearing up a “gray area” for this type of business model, he said, the legislation has helped ease RelayRides entry into California. (San Francisco also garnered the most votes in a poll on RelayRides’ website asking where the company should expand next.)

Spride Share waited for AB 1871 to go on the books before launching its pilot program with local car sharing provider City CarShare. Asked whether RelayRides considered pursuing a similar partnership for its West Coast launch, Clark commented that Spride “cemented a relationship with City Car Share early on.” That left only Zipcar as a potential partner, he said, and RelayRides did not consider linking up with the car sharing heavyweight.

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The results indicate that car-sharing has been a key catalyst for spreading the business model of using the web and social networks to share physical things. Basically it seems like after you get used to sharing a car, your attitude toward ownership in general starts changing.

Car-sharing has been so successful because cars are infrequently used and expensive items, and by joining a car-sharing service, members with the appropriate driving habits can save money. As the Latitude study puts it, cars have traditionally had a “high barrier to ownership or a high burden of ownership.” Latitude says that 69 percent of those surveyed said that they’d be more interested in sharing their stuff if they could make money from it.

Already, Zipcar, a decade old startup with the country’s largest car-sharing network, has a fleet of 7,000 vehicles and more than 400,000 members, and is planning an IPO. According to forecasts from research firm Frost & Sullivan, the number of drivers using car-sharing networks increased 117 percent between 2007 and 2009 in North America. Within five years, the firm expects to see 4.4 million people in North America and 5.5 million people in Europe (where Zipcar hopes to expand its presence beyond London) sign up for car-sharing programs, more than tripling membership from 2009.

Latitude says with this growth in mind, emerging “sharing enterprises would do well to seek partnerships with car-sharing and like services, seek out users of other sharing services as new customers, and begin offering other items to share once established in a category.” In other words: piggyback on or buddy up with car-sharing services, if you want to find the like-minded early adopters.

In a world where there will be an estimated 9 billion people on the planet by 2050 — more than 2 billion than there are today — largely with population growth happening in cities, sharing resources and vehicles will be one of the only sustainable answers. Particularly sharing of cars will be needed when the planet is also facing a shift to a new era of constrained resources, where the traditional way we generate energy is increasingly unsustainable. More efficient use of cars will lead to less oil consumption.

So, woo-hoo for car-sharing! The gateway drug of the web-sharing economy is catalyzing collaborative consumption.

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But I think there’s another often overlooked aspect at the heart of this cultural shift: how to manage constrained resources sustainably in the face of massive population growth centered around cities. There will be an estimated 9 billion people on the planet in 2050 — more than 2 billion than there are today — and largely that population growth will happen in cities. According to the United Nations around 70 percent of the world population will live in cities or urban areas by 2050, up from 49 percent today.

At the same time the population grows — and partly because of it — the planet is facing a shift to a new era of constrained resources. Fossil fuels, and thus the traditional way we generate energy, is increasingly appearing unsustainable due to a number of factors: burning fossil fuels causes climate change, the imbalanced concentration of fossil fuels creates global political instability, and the idea that the world’s available known petroleum reserves have peaked (and if you don’t believe in that, then you can agree that fossil fuels are a finite resource, unless you want to wait a million more years for organic matter to carbonize).

When There’s Too Many People

So how do you provide energy, goods, water, and food for 9 billion people, who will concentrate in cities, on one planet, which isn’t getting any bigger any time soon? There’s going to be a lot more sharing involved. And we can thank the Internet — for the first time in history — for delivering a network that is far-reaching enough, low cost enough, and easily accessible enough, to facilitate that kind of sharing between strangers.

Many of the early successful collaborative consumption driven websites have tended to emerge around cities, like car sharing service Zipcar, for example, which enables subscribers to rent out shared vehicles that are parked at public locations in cities. Cities have limited parking spaces and garages, while residents are often times already commuting via public transportation, so car ownership is less of a necessity.

As an avid City Car Share member (a company that is basically a non-profit version of Zipcar) I can tell you from my own experiences that I’m only able to weave the car sharing service into my daily life, and not own a car, because there’s so many City Car Share cars clustered in my urban neighborhood in San Francisco. It would be difficult to repeat the experience in suburbia, where owning a car and commuting to work is a necessity.

Densely populated cities offer the optimal environment for this type of sharing. There’s not a big incentive to get involved in a sharing web site — say, to find or loan a drill (which was the inspiration for Zilok) or a car  — with your neighbors when there’s few neighbors and few goods to choose from. Or at least you don’t need an Internet service to help facilitate that — you probably already know who to ask in a small community. Small dwelling spaces in cities also go hand in hand with web-based sharing services, and the studio apartment owner could prefer to rent peer to peer goods, rather than own and have to store something in a small apartment.

Efficient Use of Resources

The Internet — though its social network capabilities — is uniquely able to break up the ownership of a good into an efficiently managed service revolving around access. Basically you can eek out a whole lot more use out of a good when you can finitely manage the time and usage of it within a specific population.

Author Rachel Botsman explained the environmental aspects of collaborative consumption in an email to me through the idea of “idling capacity,” or the waste that exists in the stuff we own but rarely use. For example, the car that sits idle twenty-three hours a day or the spare bedroom that is rarely used. In the U.S., Botsman says “80 percent of the items people own are used less than once a month,” and collaborative consumption is “the reckoning of how we can take this idling capacity and redistribute it elsewhere.”

The ultimate idea is to have our economy value units of usage over units sold, and then the notions of “eco-efficiency and business efficiency align,” explains Botsman. In that world, sustainable design and longevity of goods become much more important in the production process. Car sharing might represent one of the largest available efficiency gains and Botsman says that “one car share gets approx 7-8 vehicles off the road.”

Internet As Enabler

The Internet is also uniquely able to facilitate these collaborative consumption sites because it can build trust among strangers. Zimride CEO Logan Green told me that a trusted ecosystem is at the heart of the Zimride ride-sharing service, and, for example, three companies that work in an office park are comfortable pooling together their users for rides because they’re corporate neighbors. Or college students know that the other car-poolers on Zimride will be other students, so there’s a level of trust that the ecosystem provides. Airbnb provides reviews and a social network function to help build trust for its renters and rentees.

Web-based collaborative consumption is all part of how the Internet can use bits to allocate atoms. In the cases of Airbnb and Zimride, it’s using bits to share atoms. In other cases, like digital music downloads replacing CDs, or e-books replacing paper books, it’s bits replacing atoms. In some circles replacing physical goods, with digital ones, is called dematerialization, and we organized a panel around the topic for our last Green:Net 2010. When it comes to energy efficiency and sustainably managing resources, bits will be the answer to effectively allocating atoms.

For more research on the intersection of green and IT check out GigaOM Pro (subscription required):

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Images courtesy of Zipcar, Zimride, Katie Fehrenbacher, and ~Firas‘ Flickr page Creative Commons.