To match the conductivity of copper, how much larger must an aluminum wire be in cross-section?

The conductivity of a material is a crucial factor when considering its use in electrical applications. Copper has a higher conductivity than aluminum, which means that to achieve the same level of conductivity, an aluminum wire must have a larger cross-sectional area.

In the case of aluminum compared to copper, the rule of thumb is that aluminum needs to be about 1.66 times thicker in cross-section to match the conductivity of copper. This is due to aluminum's lower conductivity, which is approximately 61% that of copper. As a result, to compensate for this difference and ensure that the aluminum wire can carry the same amount of current without overheating or experiencing excessive voltage drop, the cross-sectional area must be increased significantly.

Choosing an aluminum wire with 1.66 times the area of a copper wire ensures that the electrical resistance remains comparable, allowing the aluminum wire to perform equivalently to the copper wire in circuit applications. This calculation is essential for electrical engineers and professionals who work with wiring and conductors in residential, commercial, and industrial applications.