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Turning poop into power, not pollution

Move over solar and wind power, there’s another renewable energy source: poop. Thanks to rapidly advancing “digester” technologies, it’s possible to extract and refine natural gas from the methane in human and animal waste, generating power rather than polluting greenhouse gases. Special correspondent Dan Boyce of Inside Energy and Rocky Mountain PBS reports.

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  • JUDY WOODRUFF:

    Now a unique look at a completely different kind of power: the potential of organic waste as a renewable energy source.

    A fair warning of sorts for those of you either preparing or eating dinner, given the subject matter.

    Public Media’s Inside Energy and Rocky Mountain PBS Dan Boyce explains.

  • DAN BOYCE:

    Jon Slutsky has been milking cows since the early 1980s, his professional life rising and falling with what his livestock excrete, and not just from their udders.

  • JON SLUTSKY, Co-Owner, La Luna Dairy:

    It’s like a buffet for the manure connoisseur.

  • DAN BOYCE:

    Manure, the dirty dark side of working with these adorable Holsteins, is the enormous logistical challenge of dealing with waste. Slutsky considers himself an environmentally conscious guy, so he worries about all the methane produced as that manure breaks down.

  • JON SLUTSKY:

    Then the whole methane thing and greenhouse gases, all of that is more important to many in our industry.

  • DAN BOYCE:

    If only he lived about 50 miles southeast. This is Heartland Biogas, a new facility bring in truckload after truckload of manure from nearby dairies. All of the buildings and pools here add up to what’s called a digester.

  • BOB YOST, A1 Organics:

    You can think of the digester the same as your own guts, if you can.

  • DAN BOYCE:

    So, this is where all the cow poop goes?

  • BOB YOST:

    This is — the cow poop ends up right here.

  • DAN BOYCE:

    Bob Yost is showing me around Heartland. What’s brought in gets liquefied, cooked up and mixed together, speeding up the production of methane. And, here, they actually want methane. With a little more refining, that methane becomes chemically identical to the natural gas drilled from underground.

    The gas produced here goes straight into a pipeline on site, just like any other natural gas.

  • BOB YOST:

    It’s injected into the pipeline and then it’s delivered to anywhere in the country.

  • DAN BOYCE:

    Destructive greenhouse gases that would be escaping into the atmosphere anyway going to good use.

    Dairy farms have been building digesters for years, but the technology is advancing and diversifying. It turns out, the way to get the most methane from your digester is to have a mixture of manure and food scraps.

  • WOMAN:

    I got the Turkey bacon guac burger.

  • DAN BOYCE:

    That’s where restaurants like Denver’s Park Burger come in.

  • T.J. MCREYNOLDS, Park Burger:

    We do have a couple of gray recycling bins, as well as bins with no bag, which is our composting setup.

  • DAN BOYCE:

    General manager T.J. McReynolds pays a little bit more for composting services on top of his trash bill. He thought it would all end up as mulch somewhere.

  • T.J. MCREYNOLDS:

    Never once did I even consider it being used for natural gas.

  • DAN BOYCE:

    Hundreds of Colorado restaurants, schools and groceries have begun sending their scraps to Heartland.

  • BOB YOST:

    There could be 25, 30 semi-loads per day eventually of food waste coming in, and then the manure is added to that.

  • DAN BOYCE:

    The company Yost works with, A1 Organics, coordinates the delivery of all that food waste. It comes in all types, a lot of it still in packaging.

  • BOB YOST:

    Well, this had sweet tea in it.

  • DAN BOYCE:

    Luckily this machine at the digester can tear all that apart to get to the valuable organics inside.

    Unfortunately, all of this is a prospect tantalizingly out of reach for Slutsky. His farm is too far from the Heartland facility, and too small to build his own primitive digester, which really only makes financial sense for operations with 2,000 cows or more. Slutsky has 1,500.

  • JON SLUTSKY:

    Well, we have a business to run, and it’s not going to do us any good if we build a digester and go out of business.

  • DAN BOYCE:

    It’s a tough position to be in: big enough to have to deal with mounds and mounds of manure, too small to make any money off it. It’s where most American dairies find themselves, their methane remaining wasted.

    But there is another source of biogas, sitting right under our noses.

  • DAN TONELLO, Manager, Persigo Wastewater Treatment Plant:

    This is what eight million gallons of sewage a day looks like.

  • DAN BOYCE:

    Yes, human waste can also be turned into power. We’re at the wastewater treatment plant in Grand Junction, Colorado. And that distinctive smell of sewage is starting to smell like money to manager Dan Tonello. The plant has had a digester for decades, but most of the methane used to be flared off into the air.

  • DAN TONELLO:

    Not good for the environment and a waste of a wonderful resource.

  • DAN BOYCE:

    So the city spent just under $3 million for the natural gas refining equipment. And, rather than just putting it into a pipeline or generating electricity with it, Tonello had another idea.

  • DAN TONELLO:

    In the evening, when the trucks are done with their routes, they hook up, fill up.

  • DAN BOYCE:

    Grand Junction has been replacing an aging fleet of garbage trucks and buses with natural gas vehicles fueled mostly by the human-sourced gas from the treatment plant. Tonello says Grand Junction is the first city in the nation to do that.

  • DAN TONELLO:

    We’re looking at hundreds of thousands of dollars a year being saved by implementing this process.

  • JOANNA UNDERWOOD, Energy Vision:

    That’s a model for small wastewater treatment plants anywhere in the country.

  • DAN BOYCE:

    Joanna Underwood works with Energy Vision, an environmental group which promotes the use of this renewable natural gas. She says using biogas to run a fleet of vehicles is the most efficient way to use a digester.

  • JOANNA UNDERWOOD:

    Every time you convert a bus fleet or a refuse truck fleet or a produce delivery fleet to renewable natural gas, you have had a huge impact.

  • DAN BOYCE:

    Because, more often than not, those natural gas vehicles are replacing older, more polluting diesel trucks. Underwood says, if all the organic waste in the country were gathered from dairies, food producers and sewage plants, current technologies could produce enough natural gas to replace about half of the diesel fuel used in the U.S. transportation sector.

    And wastewater treatment plants could provide as much as 12 percent of the nation’s electricity, turning waste into a serious powerhouse.

    For the “PBS NewsHour,” I’m Dan Boyce reporting from Grand Junction, Colorado.

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