In the mid-1990s, an eco-entrepreneur designed and built a geodesic dome home in the woods near Brainerd, Minn., using a kit from Natural Spaces Homes in North Branch, Minn.

The unusual home was a project of the Water Foundation, which invested $1.75 million into packing the home with 20 conservation technologies, including solar panels, two geothermal systems and a wind turbine.

"It was a labor of love," said David Winkelman, who started the organization and acted as general contractor on the dome home. "The idea was to run a building on its own power and resources. It was way ahead of its time."

The home, which won a Green Building Award from the state in 1999, had warmth and character as well as energy efficiency. The interior was finished with seven native wood species, including red oak, butternut and white ash. Most of the wood was left unsealed, to eliminate indoor air pollution from chemicals.

Winkelman, who founded Water Foundation, never lived in the home; he lives next door. Instead, he hosted tours and events there.

"It was a model home for people to see conservation technologies in action," he said.

He estimates that 80,000 people have been through the home over the years. "It was a popular business meeting place — such wonderful surroundings."

The dome home is actually two connected domes. There's a 5,174-square-foot living dome with an open floor plan, kitchen, bedrooms and 30-foot ceilings in the great room. A second 1,600-square-foot dome functions as a family room or game room. Both have 18-inch-thick walls and the triangle-shaped structural membranes that make geodesic domes the strongest supporting structure that can be built. "Wind flows right over it," said Winkelman. "In 1998 there was a tornado. I could hardly hear it."

The property also includes a greenhouse dome, a shed and a tornado shelter made of concrete and steel.

There's even a recording studio. "I'm a musician and do radio," Winkelman said.

About eight years ago, Winkelman closed the Water Foundation, which he no longer had time to run, and put the dome home on the market.

Vessela Kouneva and Kalin Kounev, who live in Shoreview, came across some photos and were intrigued.

"The amazing shape really grabbed me," said Kouneva. "We did some research and decided we had to go see it."

They weren't disappointed when they visited.

"It's spacious, with so much light," said Kouneva, who also liked the scent of all the natural unvarnished wood. Kounev, an engineer, appreciated all the innovative technology.

The couple bought the dome home as a getaway spot.

"It's a wonderful vacation home," said Kounev. "We've had amazing parties."

The home remains extremely energy-efficient. The wind generator tower creates electricity to power the home, and couple sell the excess electricity to the local utility, netting about $100 each month.

The couple are selling the dome home because they're "thinking of moving away from Minnesota," said Kouneva, perhaps back to their native Bulgaria.

"We thought about making it a retreat center, but we don't have the time or energy," she said. "We've been its stewards for eight years."

They're hoping to find a buyer who "appreciates all the technology and can find a way to use the whole property."

Priced at $449,000, the dome is set on 2.13 wooded acres. There's a large pond that functions as part of the geothermal system. There's also a smaller pond and waterfall in front of the house with forms sculpted by an artist which create whirlpools that allow the water to clean and oxygenate itself.

The five-bedroom home has composting toilets that use waste to create usable black dirt. There's also a parking lot with 10 stalls and an attached garage.

And Winkelman still lives next door. "David mows our property," said Kouneva. "That's just such a blessing."

The couple are selling by owner. Contact Kalin Kounev, 612-524-8884. For more information, visit Palmer • 612-673-4784