Case Study 2: Sun responsive shading

This interactive shading system—designed originally by recent architecture graduate Brent Vander Werf for the University of Arizona’s entry into the 2010 Solar Decathlon House competition—utilizes a bi-metal element in combination with shade fabric to create a self-regulating system that requires virtually no maintenance. Vander Werf’s “Compliant Shading Enclosure” [patent pending] creates a movable mechanism set within the air gap between the double glazing of a wall in the UA’s solar house. Powered by the energy of the sun, the mechanism expands or closes in response to heat levels in the airspace to make the fabric opening the correct size to meet the desired comfort level.

A slight change in temperature makes the bi-metallic alloys produce an opposing force, causing the element to deform and rotate to open or close the fabric membrane.

“By placing the bi-metal element within the sealed glass, like many double-pane window systems,” says Vander Werf, “an increased amount of temperature change can be obtained due to the greenhouse effect, and a passively actuated heat sensor is achieved with a wide range of rotational motion and force exertion.” By adjusting the parameters of the alloys, the mechanism can be set to match a variety of climate conditions.