This alum-founded startup is turning campus food waste into fertilizer

Walk by Posvar Hall on Roberto Clemente Drive, and you might spy a green Ecotone Renewables shipping container that’s home to some of Pitt’s hardest-working employees: microbes that every day are turning food scraps into fertilizer.

It’s a project that’s been in the works for years, bringing together Pitt’s ambitious sustainability goals, an alum’s passion for business and ecology, and the complex task of preventing waste while providing students thousands of meals per day.

“At the University of Pittsburgh, sustainability and innovation go hand in hand,” said Assistant Vice Chancellor for Sustainability Aurora Sharrard. “We’re looking to reduce landfill waste by 25% by 2030. Ecotone is a great partner in that work as part of multifaceted solutions to reducing and responsibly managing food waste at Pitt.”

That’s no simple issue. Surplus food at Pitt dining halls is distributed to those in need by Food Recovery Heroes, for instance, and recent efforts like a shift to USEFULL stainless steel dining containers are reducing the use of single-use plastic takeout containers.

Even then, there’s more to do: As Sharrard puts it, “not every piece of food will make it to someone’s stomach.” The University has been composting since 2014, but that process has its own limits.

Enter Ecotone Renewables. The company, including cofounder and Pitt alumnus Kyle Wyche (A&S ’19, BUS ’24G), won Pitt’s Sustainability Challenge in 2023, receiving $300,000 to partner with the University to tackle the problem of food waste.

Ecotone operates two of its shipping-container ZEUS digesters on campus: one that receives organic waste from The Perch at Sutherland Hall, and another beneath Posvar Hall that takes scraps from food trucks along with coffee grounds from across campus and other sources. Combined, they process more than one ton of waste each month — and they’re just getting started, with three more digesters planned for Pitt’s regional campuses in the next year.

A stomach in a shipping container

Short for Zero Emission Upcycling System, Ecotone’s ZEUS digester is what’s called an anaerobic digester, meaning it breaks down waste in the absence of oxygen. Peek inside, and you’d see something like the tiny-house version of a research laboratory, with snugly fitted tanks, a sink and a control system.

To use it, one simply dumps a compostable bag full of scraps into a chute on the side of the digester. 

“We take that food waste and turn it into a smoothie that goes into a series of pipes and tanks, and there’s a large tank that’s called the stomach,” Wyche said. “When it burps, we trap that gas so we can use it to produce energy.”

If you’re starting to notice an anatomical theme, that’s by design: ZEUS operates much like a digestive system, housing microbes that break scraps down into useful substances, along with temperature and acidity controls that keep those microbes in peak condition. Wyche’s language also reflects his Pitt education. Before getting his MBA, he earned a BS in ecology and evolution from the Kenneth P. Dietrich School of Arts and Sciences.

“When I studied ecology and biochemistry here at the University of Pittsburgh, I learned a lot about gut bacteria and gut health and human biology,” Wyche said. “This is almost mimicking that biology.”

[Read more about Wyche’s story in Pitt Business magazine.]

Ecotone started as an aquaponics company in 2017 before pivoting to the problem of food waste. Led by Wyche along with CEO Dylan Lew and Sales Exec Elliott Bennett, the company has expanded to 13 employees, and the trio of leaders landed on the 2025 Forbes 30 under 30 Energy and Green Tech list.

Small but powerful

Wyche and his cofounders aren’t the only ones trying out this type of waste processing. Anaerobic digesters can be found around the world at a massive scale, often for the purpose of producing biogas, a mixture of methane and carbon dioxide that can be burned as fuel. That application requires lots of caution about what goes into the digester, but Ecotone’s priorities are different. 

ZEUS is tuned to handle any kind of organic waste, making it as easy as possible for anyone to use, and the company focuses on fertilizer as the main output. Add the small size and portability of the digesters, and you have a product that fills a sustainability niche that anaerobic digestion hasn’t previously been able to fill.

As they work with partners to service their growing number of digesters, Ecotone is also refining their process to make it smoother and more automated. “Our operators go into the field, and they are able to then share that feedback with our engineers,” said Wyche. “And our engineers come back and create a system that’s even more effective for our customers.”

The resulting liquid fertilizer, which the company calls Soil Sauce, is bottled and distributed to local farmers and retail locations. Some is also kept by Pitt, where Office of Facilities Management crews are experimenting with using it to help campus trees and flower beds grow.

Another key partner on campus is Pitt Eats, where sustainability director Emmy Ray (BUS ’24G), trains staff on how to properly dispose of waste in the digesters and helps ensure they are being used. Also a Pitt graduate, Ray has been excited to see the University’s second-largest dining hall get its own digester as it had proved challenging to compost at the space.

“The partnership really has been beneficial, because now we have a way to take our food waste, put it in a machine, and create something super cool that we can use across campus,” Ray said.

Photography courtesy of Steel City Visuals