Michigan University Uses Excess Mayonnaise To Generate Power

In the quest to tap into renewable resources to power our homes, businesses, farms and industries, biogas is a particularly attractive option for its ability to take any organic material and turn it to power—a fact not lost on Michigan State University this past winter, when more than 1,200 gallons of mayonnaise was converted to fuel.

Atlas Obscura reports that last December, temperatures around the Midwest campus turned freezing and caused 500 containers of dining hall mayonnaise to turn. Every one of those containers held 2.5 gallons of the creamy white stuff, which was shipped to the school and served to students—who quickly complained that the flavor was off, The State News reported.

University policy is to donate unusable food to the local food pantry. But in this instance, the quantity was just too enormous for the food bank to take the donation.

Faced with the conundrum of too much mayonnaise and no one to feed it to, it was time for some innovation. That’s where Michigan State University’s sustainability officer Carla Iansiti came in. She realized the school’s anaerobic digester, which powers several buildings on the south side of campus, might gobble up the mayo and make energy with it.

“[With] that amount of weight, I couldn’t justify just throwing it away,” Iansiti told The State News.

Anaerobic digestion is a natural occurrence happening around us all the time. The process involves microorganisms consuming organic material in the absence of oxygen. The result is biogas, which if trapped in sealed tanks can be combusted to create electricity and heat. Anaerobic digester machines do just that, turning the biogas into power. Biogas can also be processed and made into a renewable natural gas and transportation fuel.

The anaerobic digester at Michigan State University was installed in 2013, and gobbles up around 17,000 tons of organic waste from campus farms and dining halls each year, generating 2.8 million kilowatt hours of electricity. The machine is particularly fond of foods high in sugars and fats. Could there be a more perfect offering for it than mayo?

Twelve volunteers teamed up to pour all 1,250 gallons of the mayonnaise into a dumpster, which was then poured into the anaerobic digester while the mayo containers were thoroughly cleaned out. The whole process took about eight hours.

“It felt really good,” said Cole Gude, Michigan State University’s Culinary Services Sustainability Officer. “It’s one of those things of sustainability where you have this horrible situation and, because of the technology we have and the driven people we have at MSU, we have the ability to turn it into something good.”

Curious about having an anaerobic digester at your place? Here’s a lot of “digestible” information on the topic. Be sure to also check out these sweet instructions on how to make your own.