Carbon-Neutral in the Windy City: A Geothermal Chicago Home

The best-kept secret in green building—a hybrid geothermal-solar energy system—puts a luxurious Lincoln Park home a step ahead.


The reflection in this expansive mirror adds an enlarged perspective to the front hallway.

Photo By Barry Rustin

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Michael and Beth Yerke’s house might look like any other home on Chicago’s upscale North Side, but this is one case where looks certainly are deceiving. This home’s cutting-edge energy infrastructure and high-tech green materials make it one of a kind—even in a city that’s working hard to be the nation’s greenest. The home stands alone as Chicago’s first entirely carbon-neutral, all-renewable-power home—and its renewable energy system will pay for itself in about five years.

Designed by architect Patricia Craig, the stately 4,500-square-foot home meshes well with its neighbors, classic brownstone buildings in Chicago’s lively Lincoln Park neighborhood. But the home is much more than just a pretty face, thanks to the involvement of David Dwyer, founder of American Renewable Energy, a company that designs, finances and builds renewable energy systems for homes, businesses and communities. Dwyer used multiple renewable energy sources and energy-efficient strategies to build the home to Energy Star standards and thus to reduce its carbon dioxide emissions to nearly zero. (Carbon dioxide from burning fossil fuels contributes to global warming.)

A geothermal energy system, complemented by a solar thermal array, provides the Yerke home with forced-air space heating, radiant in-floor heating, air conditioning and hot water. Several gas fireplaces help warm extra-cold Chicago winter nights—the couple offsets the home’s minimal electricity and natural gas use by purchasing carbon-emission offsets and renewable energy credits.

Green energy pays off

Under the Yerkes’ foundation, 22 loops of pipes, called geothermal wells, reach 80 feet into the earth and circulate a solution of water and glycol, a natural additive that absorbs heat and functions as antifreeze. In summer, heat from the air is pulled from the house into the water/glycol solution and transferred to the earth. In winter, the system works in reverse to heat the home.

A six-panel solar energy unit complements the geothermal system, providing heat for the home’s hot water and radiant heat to the basement floor. When Chicago winters get extremely cold, the solar panels add to the heat from the geothermal system.

Michael, who books shows for Chicago’s House of Blues—a global entertainment company famed for its live music and Southern-inspired cuisine—and Beth, a graphic designer, chose their renewable-energy system based on the long-term financial benefits.

“David first laid out the costs of a traditional heating and air conditioning system versus the costs of the renewable system,” Michael says. Dwyer estimated that the annual operating cost of the renewable system, without adjusting for inflation, would be approximately $5,460 less than a conventional system. His projection reflects the fact that the renewable systems use no natural gas. “Natural gas inflation has been far more dramatic than that of electricity,” Dwyer says.

Although the initial cost for the renewable system is greater, the Yerkes received a rebate from the Illinois Department of Commerce and Economic Opportunity through a program designed to encourage renewable energy use. With the rebate and lower operation costs of the renewable system, the Yerkes’ additional investment should be returned in four to six years. “After that, we’re ahead of the game,” Michael says.

Although they installed the system before their daughter, Carolina, was born, the couple now relishes how it keeps her basement playroom constantly comfortable with radiant in-floor heat. “We’re very glad we chose this system,” Michael says. “It’s good for the environment, it’s quieter and it saves us good money on heating and cooling.”

Creating a welcoming, sustainable home

With the energy infrastructure savings established, Michael and Beth focused on creating a sustainable, inviting interior. For the home’s flooring, they chose responsibly harvested, Forest Stewardship Council–certified Brazilian cherry with an all-natural, nontoxic resin finish. The family room furniture is made from organic fibers and wood from locally discarded trees and, like the floor, features natural finishes.

Plush furnishings and multiple fireplaces make the entire home feel comfortable. “I wanted people to have places to land when they come in,” Beth says.

Just as they enjoy the environmental and financial benefits of their house, the Yerkes also savor its warm, hospitable aspects. “My favorite features are the things that make it cozy and inviting—including the fireplaces and the lantern in front,” Beth says.  

A Conversation with the Homeowners

What do you love most about this house?

Michael Yerke:
Many things, including the amount of light and the openness—but it’s cozy. The stairs are great, and so are the fireplaces.

What advice can you offer new home builders?

Make sure you feel good about how you will interact with the builder because it could be a nightmare with the wrong builder. Don’t make the hiring decision solely on price.

The Good Stuff

• Geothermal-powered heating and air conditioning systems heat and cool without producing greenhouse gas emissions.
• Six-panel solar energy system supplies hot water and radiant heat to the basement floor and augments the geothermal heating system.
• Walls and ceilings contain expanded foam insulation.
• Windows are Energy Star labeled.
• Renewable energy credits buy electricity from wind farms.
• Carbon credits offset the natural gas the stove and fireplaces use.
• Forest Stewardship Council-certified Brazilian cherry with all-natural resin finishes was used for the floors.
• Family room lamp is made from recycled fruit crates.
• The family-room furniture, by Chicago’s Bean Products, is made from organic wool batting, natural latex foam rubber and wood from locally salvaged trees.

Adding It Up: Long-Term Savings with Alternative Energy

Lower energy bills and various rebates and tax incentives allow homeowners to quickly recoup the initial cost of geothermal systems. The Yerkes’ home illustrates this situation.

After receiving a $5,000 rebate from the Illinois state government, the Yerkes paid about $30,000 more for their geothermal system than for a traditional heating/cooling system. But because the geothermal system’s ignition is electrically powered and uses no natural gas, the annual operating cost is significantly lower. David Dwyer of American Renewable Energy estimates the yearly cost of the conventional system at $7,090 and that of the geothermal system at $1,630, a savings of $5,460 each year. At that rate, without factoring in energy price changes, the difference between the conventional and geothermal systems would be made up in about six years. Assuming energy prices continue to rise, the system may pay for itself in as few as four years. The annual savings after that time period are a net gain for the homeowners.

Energy prices’ track record makes a good case for sustainable energy systems. The Energy Information Administration, which records energy statistics for the U.S. government, maintains that the price of 1,000 cubic feet of natural gas has risen 71 percent—from $7 in 2001 to $12 in 2006. Likewise, electricity-rate deregulation in Illinois on January 1, 2007, is making prices jump 22 to 55 percent.

Dwyer factored a 10 percent annual rise in natural gas costs and 5 percent in electricity into his cost estimates. The resultant rise in the operating cost of a conventional system using natural gas outpaces that of a geothermal system, and yearly savings increase with the geothermal unit.

For information about geothermal and solar energy, visit .