The Georgia Tech student team, "English Avenue Yellow Jackets", is the 2022 Design Challenge Residential Division Grand Winner for the Department of Energy's Solar Decathlon. They also took home first place in the contest's new Retrofit Housing division. Their winning entry retrofitted a 102-year-old house in Atlanta's English Avenue neighborhood.

"The target was to retrofit an existing house to net zero," Aayushi Mody, the team lead said. "And, well, we exceeded the target by making it net positive. The house basically generates more energy than it utilizes." But, Mody explained, that's just the beginning.

In addition to a net positive retrofit, the English Avenue Yellow Jackets provided solutions for rainwater harvesting and graywater reuse, a financial model that included land trust subsidies, and an additional 60 years' worth of projected weather data that proved the house would stay net positive even in cases of extreme weather.

The multidisciplinary team included students from the Schools of Architecture, Building Construction, and the H. Milton School of Industrial and Systems Engineering. Their combined expertise brought financial modeling, building science, real estate development, market analysis, use of building materials that have lower embodied carbon, and architectural design to their submission; which Mody said was Georgia Tech's greatest advantage in the competition. The result of their collaboration, Mody said, is a replicable model for any community in the United States.

"The project we developed is divided into two parts. There's a financial part and a building science part. For both parts we developed a framework that can be replicated based on various weather conditions in different locations," she said.

"We designed a framework of strategies -- or the envelope of the house, the layout of the rooms -- that keeps user comfort as the focus. You can modify the data for different climate regions, but the overall framework is something that can be replicated in any area of the country."

High Performance Building at Tech

More than a chance to show off interesting gadgets and data modeling ability, Mody said her team wanted to help a community that neighbors the Georgia Tech campus. She's a member of the High Performance Building Lab in the School of Architecture, directed by assistant professor Tarek Rakha. 

"We are focused on serving underserved communities," she said. "Climate change is going to effect underserved communities the most, and we are trying to make their lives easier by providing them a better place to live."

Rakha mentored the team, with support from School of Architecture's Flourishing Communities Collaborative Lab director Julie Kim, School of Building Construction lecturer Frank Wickstead, and School of Building Construction's Real Estate Development program director Rick Porter. The Westside Future Fund was the team's design partner, and Perkins&Will was their industry partner.

Rakha and Kim were able to introduce the team to the English Avenue community, thanks to their ongoing and award-winning work there. A growing signature of Georgia Tech architecture is its connection to community, which results in technology-rich designs based on the realities, dignity, and pressing needs of people in all kinds of communities.

"It was an unparalleled thrill to mentor this group," Rakha said. "I have never worked with 12 people that have all contributed effectively and impactfully as this team. I mentored them some times, and learned from them many times."

Rakha, who was with the team at the National Renewable Energy Laboratory in Golden, Colorado, when they received the award on April 23, shared a quote from the jury:

"The first place winner completed embodied carbon analysis to minimize carbon impact, exceeds expectations by going above and beyond in their market analysis, and developed a report so engaging that one of the jurors wanted to curl up with it under a blanket."

Collaboration Solved Everything

"Working together with this team has been the most enriching experience I have had at Georgia Tech thus far," said Samantha Morton, the industrial engineering student on the team. "We functioned differently than a typical school project, and I attribute that to the collaboration across a variety of disciplines. From the start, I could tell each member brought great skills, great knowledge, and most importantly great energy to the table!"

The English Avenue Yellow Jackets needed that variety of expertise to take on a project like retrofitting an 102-year-old house, Mody said. It was everyone on the team's first experience with a retrofit, she said, but they were able to lean on each other to learn the necessary skills.

"Pete [Choquette] actually graduated from Tech as an architect and was in practice for, I think, 18 years. He's a registered architect but now he's back for a Master in Real Estate Development. So we could learn a lot from him about how real estate works and the ways in which financial subsidies can help in a project like this. And Samantha [Morton] is getting a Masters in Industrial Engineering but she has a building science background. She's had a lot of experience in the industry."

Mody said the team's experience shaped their vision for the Solar Decathlon project, and helped them understand how things worked -- on their laptops as well as in the real world.

Choquette said his primary role in the group was to work with Ranjitha Jayasimharao and the team's professional advisor Lee Harrop of Westside Future Fund to develop a workable economic model for the project. It had to allowed for an affordable home, reduced utility burden, and give homeowners tools to generate wealth. 

"Going in, I knew our team was highly experienced and technically skilled. But the reason we won, in my opinion, is because the group began to learn how to collaborate effectively across disciplinary silos, be that finance, architecture, or building science," Choquette said. 

"Figuring out a viable, replicable model for renovating vacant, run-down housing stock into net-positive energy homes that are affordable to families at 60% of AMI is a feat that many would have said is impossible at the outset of this effort."