Beer makers use wastewater to help make energy storage cells

Engineers from the University of Colorado – Boulder have developed a bio-manufacturing process that uses a biological organism cultivated in brewery wastewater to create the carbon-based materials needed to make energy storage cells.

The pairing of breweries and batteries could set up a win-win opportunity by reducing expensive wastewater treatment costs for beer makers while providing manufacturers with a more cost-effective means of creating renewable, naturally-derived fuel cell technologies.

“Breweries use about seven barrels of water for every barrel of beer produced,” said Tyler Huggins, a graduate student in CU Boulder’s Department of Civil, Environmental and Architectural Engineering and lead author of the study.

“They can’t just dump it into the sewer because it requires extra filtration.”

The process of converting biological materials, or biomass, such as timber into carbon-based battery electrodes is currently used in some energy industry sectors. However, naturally-occurring biomass is inherently limited by its short supply, impact during extraction and intrinsic chemical makeup, rendering it expensive and difficult to optimise.

However, the CU Boulder researchers utilised the unsurpassed efficiency of biological systems to produce sophisticated structures and unique chemistries by cultivating a fast-growing fungus,Neurospora crassa, in the sugar-rich wastewater produced by a similarly fast-growing Colorado industry: breweries.

“The wastewater is ideal for our fungus to flourish in, so we are happy to take it,” said Huggins.

By cultivating their feedstock in wastewater, the researchers were able to better dictate the fungus’s chemical and physical processes from the start. They thereby created an efficient naturally-derived lithium-ion battery electrode while cleaning the wastewater in the process.

If the process were applied on a large scale, breweries could potentially reduce their municipal wastewater costs significantly while manufacturers would gain access to a cost-effective incubating medium for advanced battery technology components.

“The novelty of our process is changing the manufacturing process from top-down to bottom-up,” said Zhiyong Jason Ren, an associate professor in CU Boulder’s Department of Civil, Environmental and Architectural Engineering and a co-author of the study.

“We’re biodesigning the materials right from the start.”

Huggins and study co-author Justin Whiteley, also of CU Boulder, have filed a patent on the process and created Emergy, a Boulder-based company aimed at commercialising the technology.

“We see large potential for scaling because there’s nothing required in this process that isn’t already available,” said Huggins.