Beneath our skin is a network of tiny blood vessels that dilate to let blood flow when we’re feeling hot. The circulation of blood allows the heat to pass through our skin and cool us off. This type of ingenious cooling system is what researchers over at the Harvard School of Engineering and Applied Sciences (SEAS) are trying to replicate with glass windows.
The team of researchers developed a microfluidic circulatory system that is embedded in glass windows. Low temperature water is pumped through very thin channels to help control the heat transfer that occurs when the temperature outside the building is high.
Normally glass windows heat up when it’s hot outside and this heats up the air inside the building. This means added effort for the air conditioning system of the building to keep the temperature at a comfortably cool level.
The researchers see the new window cooling system as a way to save energy and cut down on costs. According to the team’s report on Solar Energy Materials and Solar Cells, this microfluidic circulatory system can also be applied to rooftop solar panels to help them generate energy more efficiently.
The team was led by Joanna Aizenberg, a professor of materials science at Harvard SEAS, professor of chemistry and chemical biology at Harvard, and a core faculty member of the Wyss Institute for Biologically Inspired Engineering at Harvard. The idea for the system stemmed from the microfluidics studies of Don Ingber, professor of bioengineering at Harvard SEAS and founding director of the Wyss Institute.
Microfluidics devices used in lab research and clinical diagnoses are typically small, but Ingber’s team was able to create large-scale ones by using a vinyl cutter to create a plastic mold and then pouring liquid silicone rubber into the mold. This method resulted to a thin sheet of clear silicone rubber with tiny troughs. This sheet of rubber was stretched on a glass pane to create sealed channels where water could be pumped through.
Aizenberg’s team and Ingber’s team also worked with applied mathematician Matthew Hancock, who developed a mathematical model to help predict how much energy the microfluidic circulatory system can save if installed on actual windows.
The next step for the researchers is to partner with an architecture research team to further study how the system can help save on energy when it is applied to an entire building.