Landfill gas from rotting garbage is roughly half methane and half carbon dioxide. The methane, an extremely potent greenhouse gas, is usually vented and burned off on site, but as natural gas prices have soared over the last few years, capturing that gas now has the potential to make landfill operators stinking rich. There are LGFTE projects in operation at 455 landfills across the U.S., producing 1,383 megawatts of power, but the EPA has identified another 535 sites as promising candidates that could produce an additional 1,260 megawatts.

Waste Management currently operates renewable energy projects at 112 of its landfills and is developing facilities and another 60 sites. The company aims to produce 700 megawatts of energy from those 172 projects by 2012. It’s been converting waste to energy for decades, much of it through its subsidiary Wheelabrator Technologies, founded in 1975.

But Waste Management isn’t the only company converting trash into cash. Energy Investors Funds and Enpower Corp. last year bought Landfill Energy Systems, which claims to have developed 22 landfill gas projects generating 80 MW, for an undisclosed sum.

Waste Management says energy recovery is among its top priorities, and according to CEO David Steiner, the company aims to produce enough energy from landfills to power 2 million homes by 2020. That will likely require development at nearly every landfill, an ambitious goal. But between the landfills WM owns and this new push to partner with independent operators, Waste Management could get a huge energy bump from all those dumps.

Map Courtesy of the EPA.

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Bungee Labs executive and former Microsoft evangelist Alex Barnett says thank you to Facebook for the connections it provides:

I’ve rarely used a service that has brought me so much emotional satisfaction…connecting with good friends is a feel-good thing and it is this emotional value that makes Facebook hard to beat in terms of the gratification other services can provide. So much so, here I am even writing a thank you note to the service (I can’t remember doing that for any service…I’ve written about how “cool” stuff is, or how useful some service might be…but “thank you”? Never).

Yahoo! Personals product development executive Susan Mernit is similarly grateful for the personal and emotional connectedness the social web brings, noting in a blog post that she feels “amazement at how small the world is and how the virtual universe brings people together again and again.”

But just because Facebook provides real value to users doesn’t mean that value is easily monetized (through advertising, for example). Maybe Jason Calacanis was right when he said, “Social networking is second only to chat rooms as the worst place to advertise. The content there from your friends and your family is more compelling than any advertisement.”

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