A team of Yale researchers constructed the first thermoGreenWall™ as a sustainable feature at the Urban Ecology and Design Laboratory (UEDLAB) on Science Hill this past August. The team hopes the technology will be a sustainable alternative to cooling towers, which currently provide cooling and power needs worldwide.
thermoGreenWall™ (tGW) technology can be thought of as a hybrid of standard green wall and cooling tower technology, described Alex Felson, principal investigator and Director of the UEDLAB.
Green walls are essentially vertical gardens on the exterior of a wall. Their services include passively regulating a building’s cooling and heating needs, filtering air, and providing habitat. Green walls are also aesthetically pleasing.
Unlike standard green walls, the new technology actively rejects heat, providing an alternative technology to wet cooling towers that provide heat rejection needs for district chilled water production, building cooling, and power generation.
However, while a cooling tower uses chemicals and blowdown water to treat the buildup of pollutants, tGWs can treat water onsite through their substrates and vegetation, reducing the need for chemicals.
Additionally, cooling towers lose water to the atmosphere predominately through evaporation. tGWs repurpose the water before it is released by irrigating the green wall vegetation and adding co-benefits such as improved water and air quality. The technology can also be distributed across buildings and is scalable to different heat rejection demands.
Since 2009, UEDLAB has sought to integrate engineering and biological sciences with landscape architectural design. With the tGW project, funded through the National Science Foundation (NSF), the interdisciplinary research lab has been a pioneer in advancing green wall technology and utilizing green walls in novel ways to further the environmental sustainability of modern buildings.
The team holds a patent with Yale University and the original co-inventor and engineer, James Axley. The UEDLAB is now collaborating with the Yale Mechanical Engineering & Materials Science Department’s Corey O’Hern and his research group to further refine and model the system. In addition, Graeme Berlyn, a plant physiologist in the Yale School of Forestry & Environmental Studies (F&ES), is an NSF Co-Principal Investigator. Through the NSF funding, the team has employed four F&ES graduate students and more than 12 undergraduates, including six senior thesis projects at Yale.
The team is working with Yale Facilities to develop the project. They studied the Yale Campus cooling systems and worked with engineers on campus to form an initial design for the outdoor prototype.