Closing Loops

Tuesday, July 26th, 2011

Brothers Jesse Edwin Evans and Samuel Evans plan to turn their New Chicago Brewing Company into a zero-waste facility:

The heat for brewing New Chicago’s beer will come from an anaerobic digester, which uses bacteria to convert organic waste — produced in the building and by neighboring food businesses — to biogas (and sludge, which becomes fertilizer).

The gas is then cleaned, compressed, and run through a high-pressure turbine (repurposed from a military fighter jet engine) to create electricity and 850-degree steam.

The brewery, in turn, will produce spent grains—which can be used to feed the tilapia, grow mushrooms, and feed the digester — and carbon dioxide — which will be piped to the plants in the building to make them grow faster.

“The project is about closing loops,” Edel says. For that reason, he’s looking carefully at the energy needs and waste outputs of each potential occupant. He wants to demonstrate that even the most energy-intensive businesses can operate at net zero in a sustainable way.

That’s part of the reason brewing is important to the Plant: “It’s an energy-intensive activity, it’s a waste-intensive activity, and it’s a food activity. There are no toxins; it’s pure, clean stuff, and 100 percent of the waste from brewing is useful.”

Once the digester’s up and running, he says, they’ll be selling some power back to ComEd — but “they don’t let you sell them much, because you get classed as a power plant pretty quickly.”

Vertical farms and aquaponics facilities already exist in the U.S., though they’re still relatively rare, but the Plant could very well be the first place to create a series of loops that includes an anaerobic digester, food businesses, brewing, fish farming, and plant growing. Most anaerobic digesters are used on large farms to manage animal waste, though some breweries are also implementing them for wastewater.

Anheuser-Busch began using one at its New Jersey facility in 1985 to turn wastewater into biogas and now has digesters at ten of its 12 breweries in the U.S; Sierra Nevada and New Belgium both installed similar digesters around 2002 because their wastewater was overwhelming the municipal water treatment facilities in their respective cities.

Magic Hat Brewing Company began using a digester last year that, like the one the Plant will have, breaks down spent grains as well as wastewater and converts them to natural gas that becomes fuel for the brewing process. Steve Hill, the social networking manager of Magic Hat’s parent company North American Breweries, says that the digester will save the brewery, which produces an annual 155,000 barrels, about $200,000 per year.

Anheuser-Busch’s digesters cost $5 to $10 million apiece to build, according to Gene Bocis, who oversees utility and wastewater systems for A-B’s North American zone; Magic Hat’s was $4 million (though an outside company owns it, so the brewery didn’t have to front the money). The costs are scalable to some extent — Edel estimates that the Plant’s medium-size digester will cost $2.1 million — but even a small digester is likely to be out of the price range of most new breweries. Doug Hurst, who opened Metropolitan Brewing in Ravenswood three years ago, says he thinks most craft breweries are fairly green-minded, but “this isn’t a huge moneymaking business so it’s hard to justify a large initial outlay as a small start-up.”

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