The science and technology of transparent conductors is discussed in the context of energy applications covering architectural energy-efficient windows, photothermal conversion, and photovoltaics. The overall emphasis is on architectural glazing coatings. Optical properties of heat mirrors are predicted using the Drude theory of metals. Single layer transparent conductors of aoped SnO₂, In₂O₃:Sn, and Cd₂SnO₄ are discussed. Detailed materials chemistry is given for spray hydrolysis of Sn0₂:F coatings. Multilayer metal/dielectric heat mirrors are covered including basic solar optical properties of metal films. An example system of Al₂O₃/Ag/polyester heat mirror is also detailed.