Twin Cities sewage treatments plants cut energy bills


A solar-energy installation will help power the Blue Lake Wastewater Treatment Plant.

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There’s a green revolution in the local sewage treatment trade that is yielding economic and environmental dividends.

Jason Willett, director of finance and energy for the Metropolitan Council Environmental Services Division, which operates seven energy-intensive sewage treatment plants in the Twin Cities metropolitan area, reports new developments, with business partners, that will further cut the big energy bill and carbon footprint.

Since 2006, the council’s wastewater operations have achieved energy savings totaling nearly $4 million annually, or a 20 percent decline in electricity acquired from Xcel Energy. As a result, it is no longer one of Xcel’s top three Minnesota power consumers.

The council has reached agreement with winning bidder Oak Leaf Energy Partners of Denver, which will lease up to 10 acres for a solar-energy installation paid for by Oak Leaf, that will provide about 10 percent of the energy needs of the Blue Lake Wastewater Treatment Plant in Shakopee. The plant will purchase power at below-market rates in an arrangement that’s being subsidized by Xcel as part of its conservation-and-renewables push.

The Blue Lake plant is the third-largest wastewater treatment plant in the system and handles 29 million gallons of wastewater per day from nearly 300,000 residents in 27 communities. The plant has also switched from natural gas from CenterPoint Energy to its own “biogas” generated by anaerobic digesters. That will net the plant $500,000 annually in fuel savings.

Meanwhile, a new biogas-driven electric generator will be installed at the Empire Township plant, south of St. Paul, to convert the plant gas to electric power that will cover about one-third of plant energy requirements, resulting in an annual savings of about $350,000 alone in the electric tab. Increasingly, sewage treatment plants are seen as energy source generators that will power themselves as “carbon-neutral” facilities and provide extra electricity to the grid, as well as ample supplies of fertilizer with treated waste.

Colder products seeing hot sales

It was 35 years ago that three entrepreneurs started a specialty manufacturer to make a quick-disconnect fluid coupling device for plastic tubing widely used by the medical, industrial and chemical industries.

The company, now located on once-polluted land in a St. Paul industrial park near University Avenue and Hwy. 280, was called Colder Products, because St. Paul was colder than just about anywhere.

Business is getting hotter, reports President Gary Rychley of Colder.

“Our business is innovation, and we hire most of our engineers from the University of Minnesota, just a couple miles away,” Rychley said. “We have a great workforce here, which is why we do 90 percent of our manufacturing in St. Paul. We just converted 10 more temporary workers to full-time employees. Wherever there is plastic tubing and fluids or air gases flowing, it’s a Colder opportunity.”

Rychley said the global manufacturer has nearly 300 U.S. employees and expects to grow sales 10 percent this year, its best in history, and profits by about 15 percent. Revenue has been rising at a 9 percent annual clip over the last decade.

Colder couplings can be found on products such as CamelBak water bags for hikers and bicyclists, BMW motorcycles, Mercury Marine motors and IBM cooling systems.

“In a given year, we’ll build 10,000 different configurations [orders],” Rychley said. “For blood pressure cuffs, we probably do 12 million a year for GE.’’

Since 2005, the business has been owned by industrial conglomerate Dover Corp. of Illinois.



• Atomic Data of northeast Minneapolis is on a growth track. The tech company just struck a $1.3 million, seven-year contract with Hennepin County to host its online content management and search-engine functions through Atomic’s “private cloud” of servers. The company, founded in 2001, has grown from 32 employees and $6 million in revenue in 2010 to an expected 84 employees and $17.9 million in revenue by the end of this year. Hennepin County will control the content and communications and the back-end support is designed to be invisible to users.

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