Don’t Truck Your Waste to a Landfill: Truck A Gasification Plant To Your Waste
For most of the “clean energy” startups Xconomy covers, the big question is whether the company’s prototype—be it a wind turbine, a wood-chips-to-ethanol reactor, or an anaerobic cow-manure digester—will still work efficiently when scaled up to industrial proportions. But for IST Energy in Waltham, MA, the question was how to scale down a waste gasification plant until it fit inside a standard cargo container, a space roughly 30 feet by 8 feet by 8.5 feet.
That’s exactly what the startup, a new subsidiary of engineering and defense contractor InfoSciTex, has now accomplished. Tomorrow the company is expected to launch its “Green Energy Machine” or GEM waste-to-energy conversion system, a unit that fits on the back of a truck and can shred three tons of trash per day—including paper, plastic, wood, food, and agricultural waste—and turn it into a synthetic gas mixture which can then be used to fuel electric generators or building heating systems.
In essence, it’s a mobile version of the factory-sized gasification pilot plant that Boston cleantech startup Ze-gen has built in New Bedford, MA (see my August 2007 story)—except that IST Energy uses a different kind of vessel to gasify waste, a “stratified downdraft gasifier,” in place of Ze-gen’s giant vat of molten iron. The unit takes up as much space as about three cars, and can be backed up to a building’s loading dock, or wherever its dumpsters are stowed.
The company built the Green Energy Machine in response to a request from the U.S. Army, which wants to cut down on the volume of trash, mostly from field kitchens, that it has to convoy across Iraq and Afghanistan. And IST Energy CEO and president Stu Haber says he expects the military to become one the prime customers for the machines, which will be ready for delivery this summer. But he says the GEM is also ideal for commercial and municipal facilities such as industrial plants, hospitals, universities, prisons, sports stadiums, and city waste transfer stations—”really, anybody who generates at least two tons of waste a day, which covers a huge market.” (For comparison, the town of Lincoln, MA, generates 6 tons of solid waste per day, and the Prudential Center development in downtown Boston generates 11 tons, according to Haber.)
While the machine isn’t cheap—IST will charge $850,000 per unit—its major selling point is that it can greatly reduce customers’ waste disposal and energy costs. About 95 percent of the material fed into the GEM is converted into gas, leaving an ash residue that is much cheaper to transport and takes up much less landfill space. (It also won’t emit methane and other greenhouse gases, as most landfilled materials do.) And not only does the machine power itself, but the extra gas produced can run a 120-kilowatt electrical generator or a 240-kilowatt-equivalent gas furnace. (For comparison, a typical standby home generator produces 12 kilowatts, while commercial emergency generators have outputs of 20 to 150 kilowatts.)
InfoSciTex didn’t start out in the clean energy or waste-disposal business. The company is working on an eclectic range of engineering and R&D projects in health, aerospace, software, energy, and defense, including an advanced insect repellent, a feeding bottle for pre-term infants, and an air-activated blanket for hypothermia victims. Many of its projects are a legacy of its 2005 acquisition of engineering staff and federally funded Small Business Innovation Research programs from Waltham’s Foster-Miller (which retained its robotics, advanced materials, and some other divisions and became a subsidiary of defense contractor QinetiQ).
Foster-Miller had been working on a small-scale gasification scheme, and in early 2005 it responded to an Army request for proposals for waste-management solutions for its overseas operations. “We not only outlined a solution but told them we could also provide electricity and gas heat,” says Haber. The Army accepted that proposal and several others, and the project—which became the core of IST Energy—won DoD funding to the tune of $2.5 million.
The company used the money to develop a lab prototype, then raised another $2 million in angel funding to build the first production unit, which is now parked outside the InfoSciTex building on Waltham’s Bear Hill Road (see photo).
I got a look at the unit last week. From watching a technician wriggle around the equipment inside the container, it seemed clear that one the biggest challenges for the company was 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.
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.”