Poop to Clean Power

In February 2023, LWV UMRR hosted Tracy Hodel, St. Cloud Public Works Director, talking about how St Cloud, Minnesota, is turning wastewater to energy and fertilizer and making their city more sustainable.  Now, their electrolyzer is about to come on line, and St. Cloud will have the first wastewater treatment plant in the world to produce green hydrogen and use the byproducts of oxygen and heat waste

Hodel's talk is posted on the LWV UMRR Blog at this link.  

“I feel like energy is the sexy part of it, right? Nobody wants to talk about the solids part, but it is converting something that people think of as a waste product into something very, very valuable.”

This article, from the Minneapolis Star Tribune  on October 6, highlights St. Cloud's accomplishments!  

What's the big idea
The mission of St. Cloud’s wastewater treatment plan is simple: clean the water flowing in from toilets before it is released into the Mississippi River. But why stop there? After dreaming up — and finding the funding for — a few special projects, the city is now at the forefront of wastewater ingenuity. It is using waste to make fertilizer for farmers. It is using power harnessed from the breakdown of local manufacturers’ wastewater to create 100% renewable energy to power the treatment facility. And when the city’s new $3 million electrolyzer — a device that splits water into hydrogen and oxygen — is installed in the coming months, St. Cloud will have the first wastewater treatment plant in the world to produce green hydrogen and use the byproducts of oxygen and heat waste.
 
What makes it uniquely Midwestern
The innovation is built on lofty goals and cutting-edge science, and yet it’s practical and understated. The city’s science fiction-y projects started as a way to become more efficient and save operating costs by purchasing energy from solar gardens and installing solar panels on city buildings. The city then built its own small solar array at the wastewater treatment campus in 2016. With each successful innovation, leaders dreamt up more ambitious ideas.
 
About a decade ago, former Mayor Dave Kleis set a goal for the city to be 75% renewable by 2035. It exceeded that goal by becoming 100% renewable in 2020, and today, the city produces three times as much energy as it uses. Its energy initiatives save between $1 million and $2 million each year from the city’s budget.
 
The city sells its solid fertilizer product and gives its liquid fertilizer to area farmers for free. Meanwhile, the waste-to-energy program produces heat and power for the facility at a substantial savings. The plant is able to produce energy for about 3 cents per kilowatt-hour, while typical energy customers pay an average 14 cents.
 
St. Cloud City Administrator Tracy Hodel calls it “poop to power.” She’s made stickers with the phrase to get the word out.
 
“I feel like energy is the sexy part of it, right? Nobody wants to talk about the solids part,” she said. “But it is converting something that people think of as a waste product into something very, very valuable.”
 
How it will shape the future
City leaders hope the wastewater plant will be a model for other municipalities.
St. Cloud’s new 1-megawatt solar array will guarantee 100% green hydrogen, which can be used at the facility for heating and on-site renewable energy production, and will be sold for transportation and manufacturing. The plant will also use the oxygen byproduct in its existing treatment process in which microorganisms break down waste. And they’ll capture the heat from the electrolysis process, which could potentially put the facility in a position where it no longer needs to use natural gas for heating.
“Everything we’re doing is enhancing the receiving waters, the agricultural industry, the air with the carbon dioxide emission reductions,” Hodel said. “So we’re creating a cleaner, healthier world for our future.”
— Jenny Berg

https://www.startribune.com/from-ai-to-thc-these-midwest-ideas-will-change-the-future/601479532?utm_source=newsletter&utm_medium=email&utm_campaign=st_cloud_today&utm_term=St%20Cloud