Aug. 23, 2011

Net-zero façade systems will interact with internal lighting and climate controls to collect, store and distribute light.

ANN ARBOR, Mich. – Harry Giles believes there is more to a window than typically meets the eye.

Windows offer this University of Michigan professor of practice in the Taubman College of Architecture and Urban Planning a view into how people may one-day live in and interact with the built environment in their homes and at work. Giles’s curiosity is the basis for his one-year old partnership with fellow U-M investigators and researchers from China’s Shanghai Jiao Tong University who are exploring how new, high-efficiency smart facades – windows ­­­­– can capture solar energy, store and transmit its light, and at the same time control heat transmission day or night, winter or summer.

“It’s thinking about how a building can be used most efficiently and how it consumes and generates energy in a closed loop,” said Giles.

Answering these questions will be critical to reducing the share of energy consumed by U.S. and Chinese buildings, he said, noting estimates that buildings in these countries alone will consume a combined 46 percent of global building energy by 2030.

“Our work on this challenge starts with a transparent window system,” Giles said. “The challenge is to upgrade the thermal insulation values of a window, while taking advantage of the fact that it is also light transmitting. We are looking to integrate within this system an energy harvesting component through the use of photovoltaics and to use it as a medium for not only controlling heat transfer, but for generating light.”

The net-zero window façade systems envisioned by Giles will interact with internal lighting and climate controls to collect, store and distribute light. Giles said his team’s research explores new organic photovoltaic and solid-state lighting technologies that provide great potential to harvest and generate light, while maintaining a window’s necessary transparency. Giles and U-M Prof. Max Shtein, a materials scientist are examining the organic PVs and their ability to conduct electricity across a large window span. Giles is also working with U-M Prof. P.C. Ku, an electrical engineer, on optical wave-guide technology that combines with solid-state lighting to illuminate a window area. Taubman College professors Mojtaba Navvab and Lars Junghans, specialists in lighting simulation and human interface with a building’s environmental controls, are also contributing to the analysis.

As the collaboration enters its second year, Giles looks to blend the U-M team’s technology development in materials and environmental behavior with his patent pending automated window manufacturing system together with his SJTU partners’ expertise in equipment systems simulation, prototype application and performance monitoring in full scale building component prototypes.

Prof. Harry Giles

“Ultimately, I’d envision a proven technology that would allow you to clad an entire building in this material,” Giles said. “It would offer net zero energy losses with advanced properties and added values of providing light, transparency, durability and, importantly, a new aesthetic that will combine to transform the built-environment.

“This is somewhat futuristic, but we’re trying to ground this in the promise of more near-term possibilities. We’re looking at two-year feasibility solutions, which can be transformed into longer term market-ready solutions.”

Launched in 2010, the U-M/SJTU Collaborative Research Program was created to develop new technologies that reduce global carbon emissions and their impact on the climate. The schools are also pursuing collaborative research in biomedical technologies to promote human health.  Additional U-M/SJTU energy projects funded last year include research on Li-air batteries for electric vehicle applications and high-efficiency hybrid solar cells that would improve the performance of photovoltaic solar cells. Earlier this summer, the U-M/SJTU collaborative announced a second round of funding, including energy projects that aim to improve wind turbines and electric vehicle batteries and to better understand the combustion physics of biofuels.

Contact: Paul Gargaro, Michigan Memorial Phoenix Energy Institute, 734-615-5678, pgargaro@umich.edu.