When it’s completed next year, the $10 million, 11,000-square-foot Edward and Rosalie Ginsberg Building at the corner of Hill and East University will be heated and cooled entirely by geo-exchange heat pumps powered by electricity from renewable sources.
“Geo-exchange systems are a primary strategy in our effort to eliminate all direct, campus greenhouse gas emissions by 2040,” emails Kim Broekhuizen, director of public affairs. Instead of heating or cooling outside air, “ground source” heat pumps add or remove heat from fluid circulated deep underground to remain at a constant temperature.
The $10 million, 11,000-square-foot Edward and Rosalie Ginsberg Building at the corner of Hill and East University will be heated and cooled entirely by geo-exchange heat pumps powered by electricity from renewable sources. | Photo: Mark Bialek
“Last year, approximately fifty-eight percent of U-M’s operational carbon footprint resulted from the natural gas that the university burns,” says Broekhuizen. “Our carbon neutrality infrastructure analysis estimates that a campuswide implementation of geo-exchange technology could reduce thermal energy use by approximately sixty-five percent.”
The university’s first explicit carbon-reduction target, in 2011, called for reducing “Scope 1” emissions from operations, and “Scope 2” from purchased power, by 25 percent by 2025. It achieved that three years early, and raised next year’s target to 50 percent. It aims to eliminate all Scope 1 and 2 emissions by 2040, and achieve carbon neutrality by 2050.
Two other geo-exchange projects are already underway: the Hayward Street Geothermal Facility, which will serve the Leinweber Computer Science and Information Building on North Campus, and a system that will serve the dining hall of the new Central Campus residential complex. And plans to create a districtwide geo-exchange system that will heat and cool all of its buildings are in the design phase.
The first big systems are being built on North Campus because of the availability of open land to locate the boreholes. But the university is “also investigating a layered land-use approach that includes geo-exchange underneath structures, athletic and recreation fields, open spaces, parking and pathways,” writes Broekhuizen. “We’re also studying angled drilling technologies that can minimize surface disturbance and still tap a large underground volume.” In 2021, the President’s Commission on Carbon Neutrality estimated that a campuswide geothermal system would cost roughly $3.3 billion, and be implemented piecemeal over many years.
The city’s plans are even more ambitious: It wants to be carbon neutral by 2030. In March, city council approved a $689,000 contract with the Canadian engineering design services company Stantec to assist with high-level citywide energy network planning, as well as detailed designs for geothermal systems in three areas of the city and advancing geothermal planning for specific city facilities. Creative strategies for implementing geothermal energy in urban areas include laying pipes under major roadways, parks, and additional boring on private land and public school campuses. The city is working with the university as well as AAPS, which is implementing geothermal projects at Clague and Forsythe middle schools, to ensure that the systems are compatible.
Ann Arbor’s current heating franchise agreement with DTE, which provides the bulk of the city’s natural gas, is set to expire in 2027. The city is currently considering proposals from DTE and other providers, including the utility companies Eversource and National Grid, as well as from private companies. Stantec’s plan will inform the future franchise agreement.
Missy Stults, director of Ann Arbor’s Office of Sustainability and Innovations, says that the considerations in selecting a franchise will include a “dig-once” approach and a willingness to share data: “We have goals throughout the state and we want someone who is serious enough to go on this journey with us.” Whether DTE has the capacity and willingness to change their practices, she says, is a decision the utility will have to make.
“I think there’s an existential crisis for what have been traditional gas providers,” says Stults. “Utilities across the country are facing this crisis of what do we do and what do we become.”
A full transition to geothermal heat will likely take decades, and would be paid for by the utility and possibly a bond that would be recouped through rates.
Stantec already has a contract with the city to design a geothermal system for the Bryant neighborhood, funded in part by a $182,360 grant from the U.S. Department of Energy’s Office of State and Community Energy Programs. If implemented, it would be the first existing neighborhood to be converted to a net-zero energy system, serving 262 residences, a community center, a county mental health facility, a city public works facility, and Bryant Elementary School.
Results from the Bryant neighborhood geothermal project design will inform the technical viability and cost of a citywide system, and will be used in a much larger grant proposal to DOE in October that would help pay for implementation of the project. Ann Arbor is competing against ten other cities across the country that also received the planning grant.
“The DOE grant would be catalytic,” says Stults. “I really, really want to win because of its transformational potential. It’s inspiring to be [competing] with these other folks. But I’m still gonna win,” she laughs.
