Solar Success: How the Triple Dome Became a Model for Clean Energy
Sunlight soaks into the solar array of the Triple Dome—an experimental eco-friendly model home constructed at Brigham Young University. The 17 solar panels are bifacial, meaning they generate power from both sides, with direct light from the sun or indirect light reflecting up off the ground.
“The Triple Dome produces twice as much energy as it uses, including 50 miles per day of an electric vehicle,” said Andrew South, professor at BYU. “The solar array battery grid means power goes to the house, and excess energy goes back to the grid.”
Andrew, a civil and construction engineering professor at BYU, and Evan Bingham, a BYU associate professor in construction and facilities management, became faculty advisers to the BYU Solar Decathlon team. Andrew also recently received the College of Engineering BYU’s 2023 Experiential Learning Award for his work with the Sustainability Lab.
The U.S. Department of Energy identifies the Solar Decathlon as its longest-running collegiate competition, with the goal of preparing students for the clean energy workforce and educating them in smart home solutions, high-performance buildings, zero energy design, and new technologies. The Triple Dome team became the first team BYU ever sponsored in the Build Challenge.
“One of the focus areas of the university is to be good stewards in how we treat one another and how we treat the earth, and participating in a program that helps everybody do a better job in design and construction to sustain the environment supports students as good stewards,” Andrew said.
The Triple Dome consists of three modules 12 feet wide, 28 feet long, and 11 feet tall in the center. The total structure is 36 feet wide by 20 feet deep, with spacers between the shell elements with bolted connections. The 850 square foot two bedroom, two bath home has a solar pergola that forms the carport, big enough to contain two cars.
More than 50 BYU students in civil engineering, construction management, facilities management, life science, public relations, communication, environmental science, and sustainability worked together to create and support the Triple Dome.
Erik Bingham led the students in the Solar Decathlon team. Bingham shares a last name with Professor Evan Bingham, and it turns out they are distant cousins with the same great-great grandfather. Coordinating the flow of exciting ideas of so many students while creating a viable, strong and energy-efficient structure proved challenging, Erik said.
“We all had great ideas, but we never stopped adapting our drawings to our building,” Erik said. “It’s tough to plan three steps ahead when you don’t know what those steps are, so it was trial by fire. We all were students, with tests and things that had to be prioritized, so it was a huge challenge to get the labor, but ultimately, we did phenomenal work.”
Erik said that most college students learn how to estimate, build, and complete a construction project without doing any of the actual labor.
“I wanted students like myself, who didn’t have family in the industry or connections, to be able to have hands-on experience and an idea of what the guys out in the field go through, and in that way, we were very successful,” Erik said.
BYU boasts one of the top construction management programs in the nation, and the Triple Dome project gave opportunities for students to align their world-class training with a new, cutting-edge, hands-on project so they could learn through experimenting and solid experiential learning, Andrew said.
“It takes multiple touchpoints for us to change the norms of what we do and why, and one of the greatest outcomes of students learning experientially includes learning while making a contribution to the community, challenging people, and helping them find different ways of doing things better,” Andrew said. “This project adds to the growing work for all of us to care for the earth and the resources we have as we try to be wise, serving ourselves and our communities for posterity, discovering ways to manage resources optimally across the globe.”
The Triple Dome drew attention when chosen for the Utah Valley Parade of Homes, sponsored by the Utah Valley Homebuilders Association. It also was entered into the Orange County Sustainability Decathlon.
The team made every effort to enhance energy efficiency. The only thermal bridges in a Monolithic Dome occur at the two doors and seven windows, so the team installed triple-paned windows.
“The Triple Dome’s energy efficient with lower power consumption for climate control inside the building, because a Monolithic Dome has a superior thermal envelope and thus is able to reduce the amount of energy needed to heat and cool the entire place,” Andrew explained.
“Think of it like a thermos,” Erik said. “In a Monolithic Dome, there’s no spot where the insulation isn’t active. It keeps the heat when you want heat and keeps cool when you want it cool. It holds on to your desired temperature.”
Energy efficiency permeated every aspect of the project. Fiberglass bars donated by Dow Corning took the place of the steel rebar and lowered the embodied energy of the structure, Andrew said.
“When you use power, for the most part, you are using fossil fuels to manufacture your product, and that contributes to greenhouse and global warming, so lowering the embodied energy means decreasing the energy footprint to construct the building,” Andrew said.
The team worked with Monolithic to create a new pattern for the Triple Dome so that the form could be inflated as a single air form, even though it consisted of three pods. Each section could be detached for portability on the back of a semi-truck. The whole thing could be taken apart and reconstructed at a different site.
“Our design was built to be mobile, and I don’t know if I’d do that again because it introduced challenges and limitations that frankly were quite difficult to overcome from a design standpoint,” Erik said. “Moving a Monolithic Dome is a challenge due to the weight of it.”
The Triple Dome currently rests on campus at Brigham Young University, but it may be donated to a nonprofit or sold and transported to a new owner’s chosen location. It also could be used as an exhibition space or a learning lab. Erik said when the project began, most of the students did not know of the existence of Monolithic Dome structures, let alone how energy-efficient and disaster-proof they tend to be.
“The sky’s the limit with domes,” Erik said. “They’re super energy-efficient, super soundproof, and really fire resistant. Termites can’t eat through concrete. Every aspect of it is superior, in my opinion. They’re safer, better, and can be built faster than other homes. I learned a lot of good principles by building a Monolithic Dome.”