Don’t Truck Your Waste to a Landfill: Truck A Gasification Plant To Your Waste

simply cramming all of the components needed for gasification into a space the size of a very small garage.

First there’s a shredder, which tears material poured into the GEM into confetti-sized flakes. Plastic, paper, food, wood, and agricultural waste make the ideal feedstock for the machine. The shredder can also deal with glass and metal, but since these materials can’t be gasified and just end up increasing the volume of ash residue, the company recommends sifting recyclables out of the input stream.

Then there’s a dryer, which takes out most of the moisture in the shredded flakes, and a pelletizer, which compresses them into dense little cylinders resembling rabbit food. The pellets are dropped into the aforementioned downdraft gasifier, which breaks them down under high heat into a mix of methane, carbon dioxide, carbon monoxide, hydrogen, and nitrogen. Finally, this “syngas” is sucked into a generator or microturbine to make electricity, or piped to a furnace to make heat.

(Addendum, 1/19/09: The Boston Globe has a nice infographic illustrating how all of this equipment is arranged inside the GEM.)

According to David Montella, InfoSciTex’s vice president of corporate development, a big part of the R&D effort behind the Green Energy Machine went into a fairly prosaic problem: “Coming up with a homogeneous pellet that is optimized for gasification.” Says Haber, “That’s really where a lot of other companies [working on small-scale waste gasification] have failed, and it’s where a lot of our intellectual property is.”

IST Energy solved the problem by heavily instrumenting its lab prototype. “That allowed us to iterate quickly and devise the best recipe” for the pellets, Montella says.

Shredded waste (left) and pelletized waste (right)From a cold start, it takes about two hours for the Green Energy Machine to start producing gas, and at that point, it’s self-sustaining, diverting only 7 to 10 percent of the energy in the gas to run its own equipment. IST Energy estimates that customers who run the machine 24/7, at its full three-ton-per-day capacity, will save enough money on waste disposal and energy costs to pay for the $850,000 machine in three to four years. By contrast, wind turbines take 7 years to pay for themselves, and photovoltaic panels take 10 or more, according to Haber.

“There is nothing out there that does what the GEM does,” says Haber. “On cost alone, we are going to give you a solution that has a wonderfully short payback period. Not to mention that it helps the environment substantially.”

Haber is especially enthused about the machine’s ability to prevent greenhouse gas emissions. “Our ‘carbon negative’ impact is significant,” says Haber. “We’ve calculated that running one GEM unit over the course of a year would save 540 tons of greenhouse gas emissions.” That calculation assumes that the machine is running at full capacity; roughly one third of the greenhouse-gas savings comes from eliminating waste disposal and landfilling, one third from augmenting electricity supplies (thereby reducing consumption of electricity from fossil-fuel plants), and one third from augmenting a gas heat systems (reducing natural gas consumption).

A parade of prospective customers is scheduled to inspect IST’s production machine starting next week. Haber says he hopes to sell five to 10 units in 2009. Right now it takes four months to assemble one GEM unit, but Haber says that time will decrease as volume goes up and the company’s vendors become more efficient. Once it receives a few orders, the company will open a new assembly facility, probably in Acton or Marlborough, Haber says.

The biggest obstacle to selling GEMs, according to Haber and Montella, is the patchwork of regulations in various cities, counties, and states with respect to alternative generation sources. IST designed the machine to meet the Massachusetts Department of Environmental Protection’s general standards for emissions and noise, but each local government has its own regulations about what levels are permissible and where such equipment can be sited.

Then there are the electric utilities. By law, they must buy power back from customers who produce surplus electricity, but they must also be called in to certify that these supplemental power systems are hooked into the main grid properly—a convoluted process, from both a technical and a bureaucratic standpoint. Montella says InfoSciTex is almost through working with NSTAR to get its first production unit certified. If all goes well, the unit will be helping to power the company’s own Waltham headquarters within a couple of weeks.

“No one would characterize the Northeast as an easy locale” for green energy projects, Montella says.

But if the Green Energy Machine catches on the way Haber expects—and if the larger financial markets turn around—he hopes to earn his investors’ money back, and then some, by taking IST Energy public sometime in 2010 or 2011. “That will depend on our success, of course. Time will tell.”

Author: Wade Roush

Between 2007 and 2014, I was a staff editor for Xconomy in Boston and San Francisco. Since 2008 I've been writing a weekly opinion/review column called VOX: The Voice of Xperience. (From 2008 to 2013 the column was known as World Wide Wade.) I've been writing about science and technology professionally since 1994. Before joining Xconomy in 2007, I was a staff member at MIT’s Technology Review from 2001 to 2006, serving as senior editor, San Francisco bureau chief, and executive editor of TechnologyReview.com. Before that, I was the Boston bureau reporter for Science, managing editor of supercomputing publications at NASA Ames Research Center, and Web editor at e-book pioneer NuvoMedia. I have a B.A. in the history of science from Harvard College and a PhD in the history and social study of science and technology from MIT. I've published articles in Science, Technology Review, IEEE Spectrum, Encyclopaedia Brittanica, Technology and Culture, Alaska Airlines Magazine, and World Business, and I've been a guest of NPR, CNN, CNBC, NECN, WGBH and the PBS NewsHour. I'm a frequent conference participant and enjoy opportunities to moderate panel discussions and on-stage chats. My personal site: waderoush.com My social media coordinates: Twitter: @wroush Facebook: facebook.com/wade.roush LinkedIn: linkedin.com/in/waderoush Google+ : google.com/+WadeRoush YouTube: youtube.com/wroush1967 Flickr: flickr.com/photos/wroush/ Pinterest: pinterest.com/waderoush/