Innovative Net Zero — Appalachian State's Solar Decathlon House

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solar decathlon house appalachian state university boone nc bifacial photovoltaic modules canopy

Twelve years ago, I discovered the Solar Decathlon. I was a new physics professor at a small university in Georgia, and I'd received a packet from the US Department of Energy describing the competition. It was set to have its first run in 2002, so I tried to figure out how to get involved and put together an entry. We didn't have design or construction programs, however, and the physics department that I was in was one of the most dysfunctional groups of people the world has ever seen. So instead I built a house for myself and left the academic world behind in 2004.

In case you haven't heard of the Solar Decathlon before, here's what the DOE's project website says the objectives are. The Solar Decathlon:

  • Educates students and the public about the money-saving opportunities and environmental benefits presented by clean-energy products and design solutions

  • Demonstrates to the public the comfort and affordability of homes that combine energy-efficient construction and appliances with renewable energy systems available today

  • Provides participating students with unique training that prepares them to enter our nation's clean-energy workforce.

Innovative design features

In 2007, I got to see Georgia Tech's Solar Decathlon entry, and this year I got a tour of Appalachian State University's entry, the 'Solar Homestead.' I was speaking to Dr. Lee Ball's sustainable design class that day, and he graciously took me to see it afterward. I was quite impressed.

solar decathlon house appalachian state university boone nc headquarters sign

What you see at the top of the page is the solar canopy, made up of bifacial photovoltaic modules. It gathers sunlight from above and below and gets a boost in production compared to standard photovoltaics covering the same area. On Appalachian State's Solar Homestead, the solar array is rated at 8.2 kilowatts of production.

The really neat thing about the solar canopy was that it created a lot of usable outdoor space to hang out. In fact, Dr. Ball told me that when it was in Washington, DC for the competition, the Solar Homestead became a popular hangout, with students playing guitar and enjoying the outdoors under the canopy. That's probably a big reason this entry won the People's Choice Award.


solar decathlon house appalachian state university boone nc phase change heat storage

 There were a lot of cool features in this home. Here are a few:

  • A system for using a phase-change material for heat storage, which Dr. Ball said they invented and are working on patenting (photo above)
  • Mini-split heat pumps, one ductless, one ducted
  • Passive solar features that help with heating the small house

I'm certainly no architect, but I was impressed with the design of the house, too. According to the Solar Decathlon rules, the maximum size is 1000 square feet of conditioned floor area, and they solar decathlon house appalachian state university boone nc living room furniture designused those square feet well. The house didn't feel cramped at all and had some pretty neat design touches.

The living room, shown at left, had student-designed furniture, including the coffee table that opens up into a dining room table. The space also had, I thought, the right amount of windows for capturing heat and bringing in natural light without overdoing it. It's definitely a space I'd hang out in. There's a good reason they took third place for the architecture competition.

The Solar Decathlon is a winner

One problem experienced by both of the Solar Decathlon homes I've visited is the difficulty of finding a a home for the home after the contest. I don't know what ever happened to Georgia Tech's entry, but a year after the Appalachian State Solar Homestead came back from Washington, it's sitting in Boone, used for the occasional tour and some classes.

Overall, though, the Solar Decathlon is a great event. When the homes are on display, thousands of people visit them and learn about energy efficiency, cool new technologies, and solar energy. In 2011, the homes had more than 350,000 visits in the 10 days they were open to the public, according to DOE. Also, 17,000 students college students have participated since the competition began a decade ago. That's a lot of learning!

If you ever find yourself in Boone, North Carolina, go check out the Solar Homestead. Also, if you're interested in buying one, Deltec Homes now has this design for sale as a net zero energy home.


See Also...

The Solar Homestead, ASU's website for the project

DOE Solar Decathlon, the official site for the competition

Deltec Homes' Solar Homestead, where you can buy one


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Steve Larson
Nov 14 2012 - 9:47am

My cousin lives in DC. We visit them fairly often, so we try to plan our visits around the Decathlon's tenure on the Mall. Several years ago, the Park Service cancelled the Decathlon because of the damage it was doing to the Mall & moved it elsewhere. Having at the Mall attracted a LOT of folks who would otherwise not even know it exists, and gave it a great exposure. If you have a chance to experience the Decathlon when it is all set up, make sure you take advantage of it. It is a very cool deal. Also, when the NAHB Builders Show is going on, about 3/4 of the participants have their scale models on display at the show, a very cool way to display their designs. Great story, Allison.

John Mattson
Nov 14 2012 - 10:36am

BRILLIANT! The 'solar canopy" that is. Why not have every city park picnic area, every covered walkway, etc etc become a solar power plant? Why does solar have to be ugly? Face it, much of it is ugly. But this example shows it can be beautiful as well as functional

Steve Larson
Nov 14 2012 - 12:05pm

We just completed the Certifications on a home in Winter Park, FL which has a 13.5 KW Bi-facial canopy over a south facing patio on the back of the house. It looks very elegant and very industrial at the same time, something you have to see to appreciate. The home qualified for LEED Platinum, NAHB Emerald, FGBC Platinum, DOE Challenge Home (1st one in the US), Energy Star V3.1 & Florida's Water Star Gold. The HERS is an impressive -7, 56 without the PV. Energy Efficient can be beautiful too.

Nov 15 2012 - 11:13am

"...the difficulty of finding a a home for the home after the contest." University of MN's 2009 entry sits dark and empty on campus. They may use it for some classes but I've never seen anyone in it. Still a great event, just not for home sales.

Ken Bailes
Nov 16 2012 - 12:52am

I've followed this competition since it's beginning. I just figured that the houses built for competition where utilized for future teaching and research. If these houses are not used I would love to get them and put a family into them that can give everyday feed back on actually 365 daily living in them for further R & D. My organization can give the University a reciept for the cost and once the trial living period is over they can be donated back to them. The home will not even have to leave the State or County where it is located. But this is something they (University) could be doing on their own. Shame just a waste of resources.