Via Gates Notes, a reminder that buildings represent significant opportunities for energy efficiency improvements:
Buildings waste a lot of energy: Because of inefficient windows and gaps in what’s known as the building envelope, as much as 40% of heated or cooled air leaks out of the typical building. If we can drive that number down, buildings will require less heating and cooling—which will substantially lower our emissions. Aeroseal has developed a polymer that can seal ducts and other crevices; more than a quarter of a million buildings in the U.S. and Canada are already using their product. Another company, Luxwall, has developed a window that’s many times more efficient than the single-pane windows used in most buildings. And unlike double-paned windows, it’s thin enough to replace single-paned glass without having to rebuild the frame.