Lansing – The Michigan Capitol is going “green and clean” with a new geothermal heating and cooling system that officials say will be the largest of its kind at a state government building in the country.
Drilling for the 500-foot-deep geothermal field is set to start later this year as part of a larger $70 million infrastructure upgrade already underway at the 138-year-old Capitol. While it will cost nearly $4 million upfront, officials estimate geothermal will save the state $300,000 a year on heating and cooling costs and pay for itself in roughly a decade.
It will mean “utility independence, cost savings and clean, green energy,” said Tim Bowlin, chief financial officer and project manager for the Michigan Capitol Commission. “The wells have a 50-year guarantee, but we’re anticipating 100-plus years.”
The geothermal project will entail a major drilling operation, with plans calling for 224 individual “bores” that reach 500 feet below the state Capitol lawn. The holes will house vertical loop piping that carries vegetable-grade glycol transfer fluid deep underground, where it will be naturally cooled or heated and then used to do the same inside the building.
The liquid is the same type of food-safe glycol that is used in McDonald’s milkshakes, said facilities director Rob Blackshaw, but “we don’t anticipate any leaks.”
Workers broke ground on the infrastructure project two weeks ago, and the west entrance of the Capitol is expected to remain closed for the duration of the two-year job.
Crews have been busy on the west side of the building, where they’ve removed trees, stripped topsoil and demolished a parking lot used by state legislators, who will be required to park off-site when they return from summer break in August.
Michigan lawmakers authorized the $70 million infrastructure project in the 2018 budget Gov. Rick Snyder signed in June, allowing for bonding through the State Building Authority. The commission also will get its usual appropriations next year of about $4.4 million in general fund revenue and $3.1 million in tobacco settlement revenue.
While the geothermal field will eventually be hidden underground, the drilling may be the most visible component of an infrastructure project that will largely focus on upgrading the “guts” of the Capitol.
Officials took reporters on a tour last fall to highlight decrepit innards they said were in need of upgrades.
The Michigan Capitol Commission has hired Christman Construction of Lansing, EYP Architecture of New York and Strategic Energy Solutions to work on the project. It’s working with those firms to subcontract out the geothermal drilling through a competitive bidding process.
Geothermal is “the ugly duckling of the renewable energy field,” Strategic Energy Solutions said in a recent presentation. “There’s nothing sexy about it,” but it is one of the most efficient, clean and cost-effective ways to heat or cool a building.
Colorado and Oklahoma also use geothermal to heat and cool their capitol buildings. Idaho uses heat from a geothermal well.
Michigan officials are “absolutely excited” about the geothermal field project, said Capitol Commission chairman Gary Randall, who also works as clerk of the Michigan House.
“It just makes good sense long-term,” he said. “It’s got a 10-year payoff, and then we’re on for hundreds of years literally with energy costs near zero.”
The project has forced crews to cut down a series of trees outside the Capitol, including a historic Ginko tree planted on the west lawn in 1880 by the son of Michigan’s seventh governor, Epaphroditus Ransom.
“We looked at every possible way to save that tree.… but there was just no way to save it,” Randall said. “However, we did make an attempt – and we don’t know just yet (if it’ll work) – to get some offspring from the tree.”
Michigan State University’s forestry department has four “grafts” from the tree “that we have hopes for,” Randall explained.
The geothermal piping will travel below the Lansing aquifer, raising concerns about the potential impact on local drinking water. Bowlin said state officials remain highly cognizant of water safety in the wake of the Flint contamination crisis and have been meeting with local groups to discuss plans and assuage fears.
The piping is leak-proof and fused together with welds that are “stronger than the material itself,” Randall said, and Bowlin explained that grout will be used to completely seal the bores.
“I’m learning more about geology than I ever thought I’d have to learn,” Bowlin said, “but rightfully so.”