The use of thermochromic windows in office buildings improves energy efficiency across all climate zones in the United States by modulating the temperature inside, leading to a massive savings, according to a research effort led by the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL). The thermochromic windows based on the use of perovskite materials to absorb energy from the sun shift from transparent to a visibly absorbing or reflecting state. The technology mitigates...