Solid oxide fuel cells (SOFCs) are the most efficient devices yet invented for conversion of chemical fuels directly into electrical power. It contains a solid oxide electrolyte made from a ceramic which acts as a conductor of oxide ions at temperatures from 600 to 1000 ℃. This ceramic material allows oxygen atoms to be reduced on its porous cathode surface by electrons, thus being converted into oxide ions, which are then transported through the ceramic body to a fuel-rich porous anode zone where the oxide ions can react, say with hydrogen, giving up electrons to an external circuit. Only five components are needed to put such a cell together: electrolyte, anode, cathode and two interconnect wires.