Aluminum wire
Aluminum wiring is a type of wiring used in houses, power grids, and airplanes. Aluminum provides a better conductivity to weight ratio than copper, and therefore is used in power wiring of some aircraft.
Utility companies have used aluminum wire for electrical transmission in power grids since the early 1900s. It has cost and weight advantages over copper wires. Aluminum wire in transmission and distribution applications is still the preferred material today.
In North American residential construction, aluminum wire was used to wire entire houses for a short time from the late 1960s to the late 1970s during a period of high copper prices. Wiring devices (outlets, switches, fans, etc.) at the time were not designed with the particular properties of aluminum wire in mind and there were problems with the properties of the wire itself. Older wiring devices not originally rated for aluminum wiring present a fire hazard. Revised manufacturing standards for wiring devices were required.