麻豆影院

The brewers are happy to give away dirty water. The PhDs are happy to take it.

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The plan came together 鈥� where else? 鈥� at the bar.

Last April, over pints at Backcountry Pizza in 麻豆影院, Tyler Huggins (PhDCivEngr鈥�16) and Justin Whiteley (PhDMechEngr鈥�16) were honing their idea for 鈥済rowing鈥� a battery from beer 鈥� specifically, from the wastewater discharged by breweries. If successful, their invention would offer a new model for clean energy storage while reducing beer makers鈥� costs.

The two engineers faced a crossroads. Their related work as CU 麻豆影院 doctoral students was promising, but with graduation near, the job market beckoning and research yet to do, they had to decide: Could they afford to go all in on building a better battery?

鈥淭here was a lot of soul searching,鈥� said Whiteley, who鈥檇 been considering a job offer with an established battery start-up. 鈥淲e realized we had to be OK with pursuing what鈥檚 uncomfortable.鈥� Six months earlier, Huggins had cold-called Se-Hee Lee, an associate professor in CU鈥檚 mechanical engineering department, to tell him about an听idea for a new kind of electrode 鈥� the central component of any battery.

Most electrodes are made from carbon-based minerals, a finite resource. Huggins wanted to harness a better听raw material, something biological and infinitely renewable.

Lee connected Huggins with Whiteley, one of his graduate students. The pair had complementary expertise 鈥� one knew biology, one knew electrical systems 鈥� and they shared an entrepreneurial sensibility. The first time they met, they talked for hours about the possibility of cultivating听high-quality electrodes the way one might cultivate tomatoes.

The idea wasn鈥檛 outlandish. Other researchers had used biomass (fungus and timber) in experimental batteries. But听biomass is pricey, and no form of it had been shown to outperform the graphite used in a typical lithium-ion AA. That鈥檚 why battery technology hadn鈥檛 changed meaningfully since the 1970s.

鈥淎 novelty has no value until it outperforms the market,鈥� said Huggins.

With help from Lee and Zhiyong Jason Ren, Huggins鈥檚 advisor, they began tinkering with a type of fungus, Neurospora crassa, that could be grown in just 24 hours and chemically manipulated for optimal electrical conductivity. The mature fungus offered a ready-made substitute for a standard electrode.

The trick would be growing it in bulk. Enter the brewers鈥� wastewater.

A brewery uses seven barrels of water for every barrel of beer produced, and post-fermentation wastewater is rich in organic compounds that are difficult and expensive for brewers to filter. Municipal听water treatment represents a significant business expense. But wastewater just so happens to be a perfect spot for a voracious fungus to thrive. Huggins and Whiteley knew it.

So they called two of Colorado鈥檚 leading craft brewers, Odell Brewing Co. and Avery Brewing Co., to ask for samples. The reply: 鈥淵ou want what?鈥�

Once the disbelief wore off, the brewers were happy to provide all the free wastewater the engineers could handle.

鈥淲e鈥檙e taking some cost and headache off the board for them,鈥� said Whiteley.

From there, the battery-making process took shape: Seed the wastewater with spores, wait for the fungus to congeal into a jelly, then bake it at 1,472 degrees Fahrenheit.

The resulting charcoal-like substance is, in essence, a raw electrode compatible with existing battery designs. Better yet: the material performs just as well as graphite, and Huggins and Whiteley proved it.

By June, they鈥檇 secured a patent, turned down job offers and co-founded a company, Emergy Labs, to perfect their prototype.

They won鈥檛 try to duke it out with Duracell in the consumer battery market. But if all goes well, they鈥檒l adapt the technology for business use, allowing companies to store, say, wind and solar energy more efficiently 鈥� while putting breweries鈥� dirty water to work.

An eco-friendly win-win for beer lovers and energy consumers alike? Everyone can drink to that.

Trent Knoss last wrote for the Coloradan about 3D printing.

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