Earth Day is in full swing. Have you offset your carbon emissions yet? Well, there are plenty of apps and Websites out there ready to help you do just that and more. Green is the new black. Speaking of which, if you want to be green, you’d better avoid black cars and Websites with all-black backgrounds (like goth sites and sometimes even Google).

But don’t avoid us. We just decided to turn the background of TechCrunch black today in memory of Google’s noble effort last year, when its site went black in honor of “Earth Hour”. And don’t even think about printing out an e-mail (not that you would—unless it had really important information on it that you needed hard copy of like a contract or a map, in which case, be my guest).

Seriously, green apps are great and we fully support them here at TechCrunch. The first step to dealing with a problem is often to measure it. And theer are plenty of Websites that let you measure your carbon footprint such as Co2Stats, (for Websites) and Zerofootprint (for people). But all too often these turn out to be nothing more than green vanity apps, designed to make you feel good about being green, but not really impacting the environment one way or the other.

For instance, consider a Facebook app just that launched called GoRecycle411 (developed by Jerry Kelly, the former VP of finance at Mark Cuban’s 2929 Productions). You enter how many cans, bottles, newspapers, or office paper you’ve recycled and it tells you how much energy you saved and posts your achievement to all your friends via the Facebook News feed. It keeps a tally, and translates your energy into how many barrels of oil, trees, gallons of water, pounds of carbon dioxide, kilowatts of electricity, and cubic yards of garbage you save. It also keeps track of how much everyone using the application is saving.

The more you recycle, the more virtual points you get which you can spend on virtual gifts for friends like a polar bear, a windmill, or a tree. Of course, you can enter whatever numbers you want, and you still get all those good green karma points. All in all, it is better than a lot of other Facebook apps. Not only do you get to show off how green you are, but you get to shame your friends into recycling at the same time.

Another example is Greenbookings, a Dutch travel site that calculates the carbon emissions caused by your vacation and offsets that at the end of the year by investing in green energy projects. You pay nothing extra for the offsets, but you get to feel good about it and Greenbookings uses that as marketing lure to get you to book flights, hotels, and rental cars through its site. Why not, right? It is easier for one company to offset a years worth of travel-related carbon emissions than for each traveler to do so individually, and probably cheaper too. Except that who knows what Greenbookings is going to invest that offset money into. Last year, it put the money into a hydroelectric project in China. Water power is certainly cleaner than a coal plant, but isn’t China notorious for creating huge hydroelectric projects that wreak all sorts of other environmental and human havoc? I guess you just have to trust Greenbookings on that one

(Photo by Steve Jurvetson. Yes, the venture capitalist. Is it me, or is he channeling Thomas Kinkade, the “Painter of Light” in the image above?)

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They’re committed, they say, to connecting people and businesses on green issues, and teach people about ways to be more environmentally sound. Like other social networks, members can create profiles and add friends. Users also rack up Green Points and have a Green Profile, which shows just how much they care about the environment.

Greenopolis, I suspect, is designed to show that Waste Management cares about the environment more than anything else. So in a way, it’s like an advertisement. See ZeroFootprint, a Canadian company we’ve covered that also creates local social networks around carbon offsetting in partnership with cities.

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Their chief goal, says the company, is to raise awareness among individuals and groups that everything we consume has some impact on the environment. The company is fighting global warming in two ways: encourage carbon reduction, and sell offsets for the remainder.

First, they are encouraging people and companies to be aware of how much carbon they are emitting into the atmosphere through consumption (cars, heating, food, etc.) and encouraging them to find ways to lower those emissions. For individuals this is done through their emissions calculator. The company also creates white label websites for companies, groups and cities. See, for example, Zerofootprint Toronto, a sort of social network for Toronto citizens to calculate their emissions and interact with other members.

Second, Zerofootprint offers individuals and entities the ability to purchase carbon offsets directly at their “Carbon Shop.”

When large companies like Yahoo go carbon neutral, they will usually purchase large amounts of offsets via one of the official exchanges, like the one in Chicago or Montreal. Those are good for large organizations or consultants who represent them; but smaller buyers need a way to buy smaller offsets easily. That’s where Zerofootprint comes in. Want to offset a cross country flight? Purchase a CA$10 offset and the company says you are neutral.

The big exchanges are are sometimes criticized for not properly monitoring sellers to ensure proper carbon reduction. Zerofootrpint says they do not buy offsets from exchanges because of these concerns. Instead they work directly with sellers, usually tree growers, and make sure they are legally bound to leave the trees in perpetuity.

The company charges 10% over their cost when selling offsets. They say this helps cover their operating costs. Also, they buy offsets in bulk and in advance, and they have some capital risk.

Zerofootprint is actively trying to do deals with companies as well. They’ve recently signed an agreement with Air Canada that went live just a week ago. The program encourages customers to buy an offset when purchasing a flight ticket on the airline. They say they are also negotiating with Virgin Atlantic and others, they say.

The company has twelve employees and is based in Toronto. Competitors include TerraPass and Native Energy.

After meeting with the company and hearing their story, we decided to do more than just write about them. We are working with Zerofootprint to ensure that our TechCrunch20 Conference in September is carbon neutral. They will consult with us on ways to keep emissions to a minimum, and we will be purchasing offsets for the remainder. More on the TechCrunch20 blog.

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