Why Is Aluminium Used To Make Overhead Power Cables?

Overhead power cable manufacturers often make use of copper to produce their cables. They do so because coppers’ exceptional qualities of malleability and conductivity. However, what’s often overlooked is the fact is weight: aluminium is a much lighter material to work with. For example, a 16mm aluminium cable weighs less than its copper counterpart of equal length. And that’s why many overhead cabling projects now switch to using aluminium as their choice of cables.

One of the primary features of any overhead power application is that the cables used in them typically run above ground. For instance, indoor overhead power cables may run through ducting affixed to stucco ceilings and roofs. A copper cable equivalent of an aluminium cable size and dimension is much heavier. The weight of the conduit (e.g. lead pipes or tin ducting), combined with the weight of the cable itself, might add unbearable load to the ceiling structure. Because aluminium is a lighter metal, it’s used in the alu cable is a great fit for such indoor power cabling applications.

Other outdoor applications may see overhead cables strung from one power pole to another for miles on end. In winter, frost and snow often covers these cables, making them heavier than when designed. And that’s when cable weight also plays a critical factor.

An ice or snow-covered aluminium armoured cable, for example, weighs less than a similarly constructed overhead copper cable. The secret has less to do with manufacturing technologies, and more to do with the weight characteristics of the two metals.  Even though it has 61% of conductivity found in copper, an aluminum cable is nearly 30% less weighty. Hence, it makes good dense to use aluminium to make overhead power cables.