Engineering, architecture programs work to build zero-net energy home

UNL students and faculty are building a house of the future.

More than 100 students and faculty studying in UNL’s architectural engineering and construction, and architecture programs are hammering out a 2,000-square-foot house in Omaha that is designed to provide more energy than it uses. Called the ZNETH project, the zero-net energy test home is a collaborative research effort between Engineering, the Peter Kiewit Institute, the U.S. Green Building Council (Flatwater Chapter), and the Green Omaha Coalition.

The home – located in a neighborhood adjacent to the Peter Kiewit Institute – is scheduled for completion by summer 2009.

Avery Schwer, associate professor of construction systems, leads the project.

ENERGY-EFFICIENT INSTALL – Engineering students install energy-efficient windows at the zero-net energy test home in Omaha. When finished later this year, the 2,000-square-foot home should provide more energy than it uses. Courtesy photo/Engineering.

This collaborative effort began on the drawing board. Approximately 90 students submitted architectural designs for the house, with the final plan donated by Tim Hemsath, assistant professor of architecture at UNL and chair of the Flatwater Chapter.

The ultimate goal of the project is to be “off the grid” in energy usage.

“Creating a sustainable, long-lasting home with little impact on the environment is doable now,” Schwer said. In fact, he noted, our country already has the ability to build facilities that can produce more energy than they use.

Snuggled in with other small houses, this one-and-a-half story, Craftsman-style bungalow will be covered in stucco, which is durable, reusable and features low volatile organic compounds – gases emitted from certain solids or liquids.

The estimated $250,000 cost for a home this size is above average, said Schwer. While partly due to some of the environmentally friendly processes being used, the cost also factors in construction materials and recycling efforts. However, much of the excess cost will be recouped within about five years of energy savings, he added, and its resale value will be higher as well.

The project is not just about energy and environmental goals, Schwer pointed out, but about investigating effective approaches to designing and constructing sustainable buildings for future residential and commercial performance.

“This is such a great opportunity for our students and faculty to learn while doing and to create an environment in which we can continue to discover new ways to create zero-net energy buildings,” he said.

BUILD SITE – The ZNETH home build is located in the neighborhood adjacent to the Peter Kiewit Institute and Scott Residence Hall in Omaha. The home is scheduled for completion by summer. Courtesy photo/Engineering.

After the construction concludes, ZNETH will be used as a living-learning laboratory. Three UNL graduate students will occupy the four-bedroom house and continue to analyze its energy performance and determine ways to enhance it.

Student involvement is a key component of the project. Not only are the college’s students building the home, but they are serving in key administrative roles. Steve Cross, a senior in construction management, serves as the construction manager, and Thadaeus Bode, who is earning a master’s degree in construction, is investigating wind turbine and computer modeling applications.

“Our goal has been to capture our students’ imaginations to help engage them in the learning process,” Schwer said. “That’s certainly happened with this project, and we’re having fun as well.”

Freshman Carlos Kilgore, whose grandfather was one of the first black building contractors in Nebraska, is one of many first-year students learning hands-on about “green” construction.

“I’ve never done anything like this before,” he said, but added that eventually, he wants to own his own construction company and learning from the ground up is great experience.

GETTING READY – Workers discuss details of the build inside the entryway to the ZNETH house. Courtesy photo/Engineering.

According to Schwer, the house will earn the highest rating (platinum) from the Leadership in Energy and Environmental Design, which certifies nationally recognized standards for the design and construction of green buildings. It will be the first house in Nebraska to receive a platinum LEED rating.

The ZNETH home includes a number of innovative and environmentally friendly features, which also are being implemented to gain that platinum rating. For example, a garage is being built separate from the house, earning one point from LEED standards, and geothermal pipes surround the house for thermal exchange applications.

Insulated concrete forms provide a “giant cooler effect” and an effective thermal barrier, said Schwer. Fox Blocks, whose vice president is an engineering alumnus, provided the stackable forms, which create an igloo-like effect for the home’s exterior walls.

The footings for the house sit on tons of crushed rock that prevent radon and will be impenetrable to moisture.

A geothermal heat pump (to collect absorbed heat from underground) and solar cell panels are being installed as well. The planners have also prepared for further energy storage by adding the most recent solar storage batteries, which can be somewhat pricey but also provide an active shelf life of at least five years. A “tankless water heater” will also be included, which heats the water when it’s needed but not continuously, like most water heaters.

As part of the overall process, the students and faculty working on the house have been actively practicing materials reuse, as well as choosing construction materials that can someday be reused and recycled. A “retention pond” sits in front of the house in a puddle of dirt and excess concrete, stemming run-off and the loss of top soil. The leftover concrete will be buried on-site so as not to contribute to any landfills.

A plug-in for an electric car has already been placed in front of the house by the driveway and, according to Schwer, energy from the car’s large battery could power the house for a time in case of a major power outage.

Landscaping around the house also gets careful consideration; sustainable native plants and features that require little water and no irrigation will reduce excess usage.

The Omaha Public Power District has been very cooperative and helpful with the project, Schwer added. Garry Ruliffson, OPPD’s energy solutions specialist, serves as the “green rater,” providing advice and assistance throughout the process.

Ultimately, the project is about providing students with valuable knowledge and insight into sustainable building practices.

“By the time students graduate from our programs, they will have done considerable on-site work and have experience working in different roles. The benefits are immeasurable,” Schwer said.



— Story by J.S. Engebretson, Engineering