Thermo-bimetals may change cooling and shading of buildings
Doris Kim Sung is developing Thermo-Bimetal paneling, which changes shape with temperature and may let walls breathe and windows apply shading to themselves.
Doris Kim Sung is an architect with a history in biology and has been addressing an issue with modern architecture: heat. Before the advent of air conditioning, buildings were well insulated to keep them warm in winter and cool in summer. But as technology improved and air conditioning became available along with new construction techniques, our buildings moved away from insulation, trading it instead for large panoramic windows and thinner walls, essentially making them hot boxes.
As long as the power is on, such building design is fine. But when the power goes out and the AC stops working, they heat up immensely in the sunlight and sometimes even have to be vacated temporarily. Sung is developing a number of solutions which could help solve this problem, and they involve thermo-bimetals. Thermo-Bimetals are alloys which contains two separate metals layered on top of each other. If the alloys have different thermal expansion properties, then one side of the metal will expand more than the other when exposed to heat. Because of this, the thermo-bimetal curls up, and this is very useful.
Doris Kim Sung, next to some thermo-bimetal paneling
Sung is hoping to develop an automatic shading system with the material. By paneling strips of thermo-bimetal, she can create a sun shield which remains open in the shade, but closes as soon as direct sunlight begins to warm it. She has created a proof of concept for this technology, in the form of a large metallic sail which not only provides shading, but as a side-effect allows air to stream freely through the material and provide a cooling effect when the panels are open.
In the future, Sung is hoping to incorporate this material into the space between two panes of glass in a window. By filling it with many small strips of thermo-bimetal, she envisions a window which will shade itself from the sun, only in the area that's effected by the sun. Theoretically, a building could self regulate shading as the sun travels around it throughout the day.
The metal strips curl upwards when heated, allowing air to pass through
Another equally interesting concept, would be to create a building material which breathes. She hopes to manufacture a construction material with perforations which would allow air to travel through it. These would be constructed together with thermo-bimetals, which could curl around the holes, blocking them, when the metals were hot, and allowing air to pass through freely when cool.
A promising aspect of the technology is that it operates with no electricity. It's completely autonomous.