Wood has a series of tiny structures inside that are used to carry water and nutrients to all parts of a living tree. Scientists have now figured out how to harness those same small structures to keep a home cool. Researchers at the University of Maryland and the University of Colorado Boulder say that the material could save 20% in AC bills.
The research takes advantage of cellulose nanofibers and the natural vascular chambers inside wood processed in a way that creates optical properties in the material able to radiate heat away. The team removed the lignin, the component of wood that gives it strength and adds color. The result is a pale material made of cellulose nanofibers.
The wood was then compressed to restore its strength, and a super-hydrophobic compound was added to protect it. The result is a bright white building material stronger than steel that could be used to build roofs and remove heat from a building. The heat removing properties require no electricity.
Testing on a hot and sunny day in Arizona shows that the cooling wood stayed 5-6 degrees Fahrenheit cooler than the ambient air temperature, even in the hottest part of the day. It also stayed 12-degrees colder than natural wood.
The team estimates that if used in buildings constructed since 2004, the new wood would save 20% in air conditioning bills. Cooling a home in a hot environment is one of the biggest energy consumers. There is no indication of when wood of this sort might be ready for commercial deployment.