ST. CHARLES — The sun is shining and pushing power in St. Charles.
As part of a multi-state distributive solar energy project constructed and operated by BluEarth Renewables US, the city saw 2 megawatts of solar energy come online Sept. 23.
The St. Charles site is part of the larger Butter Solar Portfolio, a project that includes 10 constructed facilities in three states that will generate 22.6 MW of power for 13 participating municipalities.
"The biggest benefit to us is having that power delivered right here in town," said St. Charles City Administrator Nick Koverman. "We save on those transmission costs.”
For the city, Koverman explained, joining the project was a matter of saving money "behind the meter," meaning before the energy moves from the grid to the consumer. In St. Charles' case, that meant saving on the cost of transmitting the electricity.
St. Charles, which has its own public utility, joined the project because of the makeup of electricity costs. Koverman said that when the city buys power from Dairyland Cooperative, a large portion of that cost is made up of the cost of transmitting the power to the city over high-voltage lines. By having the power generated right next to its own substation, St. Charles avoids those costs, and the city saves money.
Joining the project happened fast for St. Charles. Eric Udelhofen of One Energy Renewables, one of the project partners, said the project went from discussion to construction rather fast.
"I was here June or July of last year and thought maybe we do this, maybe not," Udelhofen said. "And in January (2019) we had shovels in the ground."
Among the nine other sites was one more in Minnesota, a 600-kilowatt (alternating current) solar plant in Lanesboro. The other sites were mostly in Wisconsin with one solar plant built in Iowa.
In total, the entire distributed network provides enough power for 5,000 homes, said Chris Barnes, director of solar energy for BluEarth Renewables.
Udelhofen said the project differs from most solar projects by using a distributed generation model. Instead of one big site like the 100 MW North Star Solar project in Chisago County, the Butter Solar Portfolio generates a smaller amount of power in several location.
In fact, the amount generated at each site is roughly equal to that city's minimum power load during the day, Udelhofen said. That saves on the cost of managing power in a way that sells it back to the grid.
Big benefits, small costs
Koverman said St. Charles citizens will see benefits in several ways for a minimal investment. The city paid $217,000 for the land on which the site was built, but it also leases that land to BluEarth for the 25-year lifetime of the project. The city also needed to run lines from the nearby substation to the site, located behind St. Charles Borromeo Catholic Church.
However, citizens will see their electricity rates remain low in part because of the "behind the meter" savings and the steady low cost of this portion of the city's power supply, Koverman said.
In addition to the cities, the project was also helped by Organic Valley, the organic agriculture cooperative, which agreed to buy a large portion of the generated energy in order to move its own electricity usage toward a commitment to 100 percent renewable energy.
The project is one of several distributed solar projects in Minnesota. The largest of those is the 100 MW Aurora Distributed Solar Project built in 16 counties across Minnesota and permitted by the Minnesota Public Utilities Commission in 2015, said Emmalynn Bauer, director of communications for the Minnesota Department of Commerce.
That project includes a 6.5 MW site in Dodge Center and a 4 MW site near Pine Island, both of which became operational in May 2017.
Udelhofen said while both distributed solar production like the Butter Solar Portfolio project and the larger mega solar sites like North Star Solar are needed for the state to reach its renewable energy goals, eventually most small cities will have a solar power plant like St. Charles does next to its substation.
"If there's transmission capacity in a high-voltage line, it'll get used," he said. "But this project has no negative impact on the high-voltage grid."