At first glance, the recently constructed two-story house looks no different from any of the others being built in the Prairie Trail development in Ankeny.

That’s just what its builders had hoped to accomplish in constructing what could be one of Iowa’s first “net-zero” homes: a highly energy-efficient house designed to produce at least as much electricity as it uses in the course of a year.

“We didn’t want to build something that looks like a spaceship,” said Joel Clutts, a co-owner of Eco-Logic Homes, an Urbandale-based home builder that’s seeking to bring the type of solar-powered residential energy systems that are becoming common on the East and West coasts to Iowa. “It looks and feels like an Iowa house.”

Common-sense stuff

Clutts had worked as an energy efficiency consultant in the building industry for about seven years before construction activity slowed significantly with the recession. Seeing an opportunity to carve out a niche among home buyers that want to dramatically reduce their carbon footprint, he partnered with two builders, Joe Schafbuch and Dylan DeBruin, to launch Eco-Logic Homes.

Solar power for residential use is much more prevalent on both coasts due to generous incentives offered by utility companies for installing systems, Clutts noted. Working with a builder in the Boston area, he adapted a model used for solar-powered homes in that area to Iowa.

Electricity generated by 20 photovoltaic cells mounted on the roof supplies the 2,100-square-foot house’s energy needs first; any additional electricity is supplied by MidAmerican Energy Co. If the solar panels produce more electricity than needed, the excess power goes back onto the grid and MidAmerican issues a credit that reduces that month’s bill. The builders believe that over a year’s time, the credits will result in a net-zero energy cost.

“What we expect is that we’ll buy energy the most in the winter, we’ll sell it in the spring and the fall and we won’t buy it quite as much in the summer,” Clutts said. “Based on what we’re seeing from our energy costs, that’s about how it’s playing out.”

The key to achieving a net-zero house was careful design that paid attention to myriad details – ranging from passive solar techniques to the choice of ultra-high-efficiency appliances, triple-pane low-emissivity windows and tight double-wall construction.

“A lot of it is common-sense stuff that we market as ‘passive green,’” he said. “At the very least, I encourage people to consider passive solar – how does the house sit on the lot, where are the windows, what’s the exposure – and design the house around that. On this house, the garage is on the north, for obvious reasons; there are also no windows on the north side of the house. I don’t want to give away that kind of energy. I do that on a normal house that isn’t a net-zero house. That’s just smart planning. So there are a lot of things you can do that don’t cost any extra money but create a really efficient house.”

Very curious

The Ankeny house, located at 1714 S.W. College Drive, was completed late last year and has been on the market since January, listed at $334,900. The open houses held each Sunday since then have attracted more than 200 visitors, said Megan Hill, an agent with Century 21 Signature Real Estate who is marketing the property.

“More and more, people coming through have already heard of it and they’re very curious,” she said. “So they’re very excited to come in. From our standpoint, we just want to get it out there and let people know the technology is here and it’s affordable. When you are able to basically mortgage your energy cost over a 30-year period, it’s very affordable. We all know where energy costs are headed; this is a way the consumer can actually control those costs.”

The solar system, which uses Samsung 244-watt mono-crystalline solar panels, produced approximately 650 kilowatt-hours (Kwh) of electricity in April, Clutts said, referring to daily performance data that he can track using an online system. By comparison, an average four-person household might use 700 to 800 Kwh per month.

Much of the potential for the house to truly achieve net-zero performance for its owners will depend on how energy-conscious its occupants are, Clutts said.

“If someone moves in here with four teenage girls who are all using hair dryers all the time, it’s going to be pretty tough, because I’d say that’s an above-average usage,” he said. “But if someone moves in here with two kids and they’re conscious about not leaving lights on and doing other smart things in how they’re living, then yeah, we can get close to zero.”

Going forward

Though Eco-Logic’s Ankeny model home is the only speculative house it has planned, the company is working with several clients with various degrees of interest in net-zero homes, Clutts said.

“That gets kind of fun, because each person has their own kind of plan, and we have to address that separately based on the lot, the plan they want to build and how they want to live,” he said. For instance, “one person is really interested in wind. So we have to determine, is that possible where they are?”

Another prospective client is considering a solar system that would include a battery backup system that would store energy produced.

“When people want to do this, they’ve usually done a lot of research online and they’ve got a pretty good idea about what they want to use,” he said. “It’s interesting who you run into when you’ve got a model house like this.”

Other projects

Some other net-zero initiatives in Iowa have made headlines recently. Last month, Maharishi University of Management in Fairfield opened its new Sustainable Living Center, which the university said is among the first net-zero energy buildings in the nation. Equipped with 58 15-kilowatt solar panels and a 100-foot wind turbine capable of producing 10 kilowatts, the off-the-grid building is expected to produce 30 percent more energy than it consumes.

Also in Eastern Iowa, the Iowa Valley chapter of Habitat for Humanity is working with the University of Iowa Engineers for a Sustainable World to design and build a net-zero Habitat house in Iowa City.

Building a net-zero house is “definitely feasible, engineeringwise,” said Craig Just, an assistant professor of civil and environmental engineering at U of I working as an adviser for the project. “We’ll have to see if we can get the costs in line to make it go forward, because Habitat homes are more cost-stringent than most.”

There are several ways to define net-zero, depending on how narrowly or broadly you slice it, Just said. The goal for the Habitat house, which will be just 900 square feet, is to achieve net-zero total energy usage, not just electricity usage. For instance, a house that uses geothermal rather than propane for its energy needs may be considered more truly a net-zero energy user.

“There are not many net-zero homes around,” he said. “To go full net-zero, that takes quite a bit, actually.”