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Why is copper used in electrical wiring?

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A periodic table element box for copper shows its symbol Cu, atomic number 29, atomic weight 63.546, electron configuration, and name. Icons indicate copper is a solid, weakly basic transition metal with face-centered cubic crystal structure. A key explains the symbols and color coding. — copper Properties of copper.

Copper is widely used in electrical wiring primarily because it is an exceptionally good conductor of electricity. Among all metals, pure copper is second only to silver in its ability to conduct both heat and electric current.12

Its effectiveness as a conductor is due to the mobility of its free electrons, which can move easily through the metal's crystalline structure when influenced by an electric field. Because high purity is essential for maintaining this performance—as impurities can interfere with electron movement—the electrical industry typically utilizes electrolytic copper, which is highly refined.34

In addition to its conductivity, copper is highly ductile, meaning it can be easily drawn into thin wires without fracturing. This combination of superior electrical properties and mechanical workability makes it the standard material for industrial electrical applications.1254