2008 Winner Profiles
Design Challenge
Second Place
Entering the Future Efficiently
The Seattle Academy, Seattle
Austin Dickson, Mariah Gentry
Advisor: Mary Gentry
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“We learned how to develop a concept, analyze data, and put together a professional presentation. The project also gave us valuable experience in presenting the project to judges and other students.”
A Seattle Academy team, second place winners in the Design Challenge, proposed using rooftop gardens to reduce the intensity of heat islands and to lower carbon dioxide levels in the atmosphere.
A heat island is a developed urban location that is significantly warmer than a nearby, non-developed area. Heat islands accumulate excessive solar energy in the form of heat and waste energy through air-cooling systems in buildings.
Using cultivated bamboo, aerated autoclaved concrete, and stonewool, the students designed a rooftop garden that shades roofs and efficiently clears carbon dioxide. Bamboo is a fast growing plant that sequesters 35 percent more carbon dioxide than Pacific forests. Stonewool is an alternative soil that absorbs more water and allows the plants to grow up to 30 percent faster than plants in normal soil. The students chose to use aerated autoclaved concrete for the roof barrier because of its light weight.
Overall, the students’ rooftop garden design could save as much as 50 percent of energy now used to cool buildings. At the same time, it could make urban settings 19 to 31 percent cooler by adding shade and lowering specific heat rates.