Smart glass blocks heat or light at flick of a switch

Smart glass blocks heat or light at flick of a switch
Spray-on coating is a step towards energy-efficient windows.
14 August 2013
http://www.nature.com/news/smart-glass-blocks-heat-or-light-at-flick-of-a-switch-1.13558

Scientists Reach Milestone In Quest For Smart Windows
August 15, 2013
http://www.npr.org/2013/08/15/211976401/scientists-reach-milestone-in-quest-for-smart-windows

Smart windows change how much sunlight they let through on a hot day. Such windows could reduce the demand for energy by reducing the need for air conditioning.

At the Lawrence Berkeley Laboratory in California, Delia Milliron and her colleagues have been making microscopic crystals called nanocrystals out of indium and tin. As they report in today’s issue of the journal Nature, when you impregnate a special glass with these nanocrystals, you get a window that can block either the warming rays from the sun or the light rays from the sun, or both.