Electrical energy is the only product that always has to be generated at the same moment it is consumed. This is a crucial difference to all other goods and markets. Nevertheless, to ensure that the light always comes on immediately when you switch it on, a very extensive network is required. The more extensive it is, the more likely there is to be a mutual balancing of consumption fluctuations at the millions of tapping points.
If the large, high-voltage overhead lines visible from afar are also made of aluminium, because they are then only half the weight despite the lower conductivity of this light metal and the correspondingly larger cross-section that is required, the construction of such a network would nevertheless be inconceivable without copper. Even if one wants to lay the cables out of sight into the ground, there is usually a change to copper conductors, because this makes the entire cable somewhat less thick and thus more manageable. It also reduces the need for costly high-voltage insulating material, which is also a considerable cost factor.
Copper is also found in transformers, switchgear, frequency converters, control and “secondary” technology, as well as in the many large and small machines in conventional and modern generation plants.