Energy Efficient Freezers

The key to reducing the amount of energy consumed by freezers may be found in the carnivorous pitcher plant, which forms a surface so slippery, even ants can’t cling to it. In the context of refrigeration, superhydrophic materials such as the ones found in nature can stop ice from forming on surfaces, thereby reducing the need for defrosting. But existing versions can be fragile and scratch easily, which causes them to lose their slipperiness.

A new material recently developed by Harvard researchers uses a nanostructured surface that’s designed to adhere to specific lubricants.  The lubricants form a very thin liquid layer that’s smoother than any solid surface could ever be. And if scratched, the lubricant flows over the area to maintain its slick properties.

Testing indicates that in freezer applications, the new surface could reduce the energy used during a typical defrost cycle (which represents about one-quarter of the total energy consumption) by 40 percent or more. It could also be used on airplanes and wind turbines to reduce icing.