At work, local attorney Deb LaBelle deals with grim realities. Four years ago, she won a landmark $100 million lawsuit against the state on behalf of hundreds of women who’d been sexually abused in prison. In December, she filed a new lawsuit alleging that minors incarcerated with adults also are being abused.
At home, though, LaBelle can rest easy. When she built a new house near Bluffs Park in 2010, she recalls, “we wanted to ‘green up’ a little.” So architect Jan Culbertson included a geothermal heating and cooling system.
Working with Doug Selby of Meadowlark Builders, Cribley Drilling Company of Dexter sank four 200-foot wells on the property. The wells were lined with pipes, connected in a continuous loop, and filled with a fluid that’s about 80 percent water and 20 percent food-grade glycol–Culbertson calls it “a kind of high-quality antifreeze.” Pumped through hundreds of feet of pipes, the fluid emerges at a constant fifty-two degrees year round. A heat exchanger extracts heat in the winter, or adds it in the summer, and the liquid is pumped underground again. “When we say ‘geothermal,'” Culbertson points out, “we ought to say ‘geoexchange.‘”
A geothermal system can easily cost $20,000. But because fluid circulated through the underground loop returns “temperature renewed,” a heat pump can heat or cool a building using half as much energy as a conventional furnace and air conditioner. Asked this past December how her three-year-old system is working, LaBelle replied, “I love it–it’s fantastic!”
Culbertson knows geothermal firsthand: She’s a senior principal at A3C, whose Huron Street office is climate controlled using wells under a nearby alley. And Doug Selby says that Meadowlark now does about one geothermal installation a month.
Selby calls himself a “hard-working builder,” but he’s also a proselytizer for green energy. He’s aghast at how much energy is wasted. “People don’t know about houses,” he says. “They’re ignorant about how to seal a door, how to plug a drafty window. In the winter heat escapes; in the summer heat enters.” Noting that the United States has 5 percent of the world’s population but consumes 24 percent of its energy, he compares our wasteful buildings to “driving a jalopy car.”
Selby began studying geothermal in 2004. He spends as many as thirty hours working up a bid and says he has a “stable” of drillers with different specialties.
Cribley Drilling, which did Deb LaBelle’s system, has been owned by the Clark family since 1963. Tim Clark says they do about 140 geothermal bores a year. People who hire them for geothermal projects, Clark says, are “green-oriented … people who are looking at efficiency and energy cost savings.”
Typically, a residence will require four or five wells. While the drilling is relatively straightforward, grouting is a skill. After the boring teeth are extracted, a double length of three-quarter-inch plastic pipe, joined at the bottom by a U connector, is carefully fed into the hole. The pipe will carry the heat-transfer fluid. A third pipe feeds Bentonite–liquid clay, the same plugging agent used to seal the well in the Deepwater Horizon oil spill–into the hole. The clay has to completely fill the gaps around the heat-transfer pipes to make sure they don’t crimp or collapse and to create a tight bond for maximum energy transfer.
Once the loop is completed, it’s hooked up to a “ground source heat pump.” Selby says that lately, the introduction of dual-stage compressors has made these even more efficient. But he feels that the most important recent development in geothermal is psychological: there’s now widespread interest. Geothermal seems to have entered the public consciousness.
Asked how long it takes for a geothermal system to pay for itself, he says, “Somewhere around three to seven [years] if propane or fuel oil’s being used and around seven to twelve years if it’s natural gas.” Will a system last that long? “Mostly the components last a long time if the system’s well made,” he says, “but occasionally you have to change a compressor after about ten years.”
One of Selby’s customers, John Swerdlow, admits that he and his partner, Pamela Harnick, “weren’t looking for a ‘green’ house. We just wanted one with two bathrooms on the second floor.” But after eighteen months of fruitless searching for an existing home that met their needs, “Doug suggested he could find a location we could live with and build what we wanted. So that’s the way we went.”
Swerdlow, Harnick, and their two children now live in a 4,000-square-foot, super-insulated, geothermal home on Spring Street, and Swerdlow says he “couldn’t be happier.” I visited there one day when the outside temperature was nineteen and sat on a couch near a small gas fireplace. The house was extremely quiet, warm, and comfortable. “We have gas for the stove and gas here,” Swerdlow said, pointing at the modest flames, “and the rest is electrical. Our highest electric bill was about $120, and our lowest was below $40. The basement and walls were built with ICFs [insulated concrete forms]; the attic ceiling was made of SIPs [structural insulated panels].”
The heat pump is a beige metal box in the basement. Less than half the size of a refrigerator, it contains all the components necessary to draw heat from the liquid or to reverse the process. “We raise the temperature about a degree in the morning,” Swerdlow said, “and turn it down a degree in the evening. If we want to have fresh air in the bedroom we can open the windows–making certain the door’s closed tightly.”
Kathy Clark, motivational speaker and former NASA chief scientist for the International Space Station, first became aware of geothermal during a casual conversation some years ago. Someone remarked, as she recalls it, that “Al Gore talks a lot about efficiency, but George W. Bush has had it [geothermal] on his ranch for years.”
She said to herself–after the surprise wore off–“What is geothermal?” She began researching it, and then discovered, quite by accident, that her next-door neighbor on the north side had also been investigating the concept. She borrowed his notes and got bids, and two years ago Cribley drilled four wells in her front yard.
Clark and her husband, Robert Ike, hired Michigan Energy to install the rest of the system, because the Whitmore Lake company offered a lifetime warranty on its compressor and had a contractor who could drill directionally to bring the pipes into their house space without tearing up the driveway. Though getting their DTE billing straightened out has been “rocky,” Clark says, “we love our system.”
Clark says they’d stopped using their conventional air conditioning five years earlier–“it just uses too much energy”–but now, with geothermal, have efficient AC. “If you bring fluid into the house that’s fifty-two degrees, it doesn’t take much energy to cool your 4,000 square feet,” she explains.
“I wish our electricity was furnished by photovoltaic panels,” Clark adds wistfully. “But the technology just isn’t there yet. The efficiency’s not there. We’re close, but not yet.”
Geothermal isn’t just for houses: there are also some large institutional systems in the area. The city ruled it out for the new Justice Center–too expensive–but a couple of years ago, Cribley drilled 144 boreholes for Washtenaw Community College, each 450 feet deep, for a system that serves two of the school’s buildings. And Skyline High School is heated and cooled by eighty miles of buried loops.
The Skyline system is horizontal rather than vertical–the pipes were placed in shallow trenches over a wide area, which is cheaper if a site has room for it. In 2010, Randy Trent, then the AAPS’s executive director of physical properties, estimated the energy savings at more than $117,000 annually. Skyline also received an award as the largest “Silver LEED certified” high school in the nation.
The Observer staff got a close look at one of the most technically ambitious systems in town a few years ago, when the magazine was still located in the Market Place building next to the Farmers Market. For the better part of a year, the parking lot across Detroit St. was torn up to install a geothermal system.
Most systems go down only 100 to 200 feet, which in this area means they’re placed in (somewhat) loose glacial debris. But this one called for eleven wells, each 600 feet deep.
“When we put our first test well down, it was like carving butter with a hot knife,” says architect Mark Melchi, a vice president at MAV Development, the building’s owner. But later wells ran into obstacles in the ancient rocky substrate, and, even after the drilling was done, there were further difficulties connecting the parking lot to the building: a horizontal bore got almost across Detroit St.–only to run into a literal brick wall underground. The street had to be dug up to complete the connection.
Jeff Harshe, also an MAVD vice president, describes the arduous project as a kind of experiment. So far it’s only hooked up for a single office tenant, Second to None, and Melchi says they don’t have comparative data about its efficiency, because the previous tenant in that space was a restaurant. But Harshe says that as they extend the system throughout the building, tenants should benefit from “lower utility costs and less dependence on nonrenewable sources.” And so will the company: after this experience, he says, “we know how to do it” and can bring that expertise to future projects.
When the Market Place project was finally complete, MAVD owner Mike Vlasic hosted a party to show off the system–and to apologize to the tenants whose cars had been displaced for so long. He said the project “was my idea–and everybody hates me for it!” But he said it cheerfully and showed no sign of being discouraged.
“Not to step on anybody’s toes, [but] it’s the only green energy that makes sense in Michigan–that actually produces more energy than it takes to make,” he said. “Solar panels wear out, and you have to replace them about the time they’ve produced as much energy as went into them.”
Since then, overproduction in Asia has slashed the cost of solar-electric systems–but Vlasic remains unimpressed. Though prices have come down, he explains in a recent email, “the laws of physics have not changed. Photo voltaic cells convert, at best, 10% of captured solar energy into electricity, and this efficiency declines over time. Right now 25 years seems to be the outside lifespan … If you include the energy created to their manufacture, transportation, installation and removal they do not produce net energy.
“Geothermal on the other hand, has shown no tendency to decline in efficiency over time.
“Second, there is enough photo voltaic capacity installed around the world to show that photo voltaic requires [twice] the investment to be useful … because people do not want to sit in the dark when the sun is not shining, and we have no practical way to store the large amounts of energy we are talking about, we need to invest in photo voltaic capacity AND an equal amount of alternate generating capacity.
“Geothermal, on the other hand is 24/7/365, so the investment in geothermal, though high in the front end, does not require an alternate energy source at night. Mother earth does the energy storage for us.”
Vlasic says he floated a proposal to build a much larger well field under the Farmers Market to serve nearby buildings, but got a cold shoulder from the city because his company wasn’t a nonprofit. He hasn’t given up, however–“I still consider geothermal to be our ‘true renewable’ in the northern hemisphere.”
He says he’s thinking about including geothermal in an office park the company is developing outside of Denver. When it comes to alternative energy, Vlasic believes, underground is the place to be.