Losses abound - The lowly secondary

The secondary is the conductor that runs from a service transformer to the meter at the service entrance for a premise.

The purpose of the secondary is to distribute electricity at its lowest voltage to the premise, since energy is a product of voltage times amperage, it also means the highest amperage.

When it comes to losses, it is not the voltage that causes them, but amperage. High amperage results in conductor heating, and hot conductors have higher impedance which causes more losses.

In a recent study of secondary conductors, the older the premise, the smaller the secondary conductor and the higher the losses. The smaller and longer the conductor, the higher the losses.

Now if we add electric vehicles, PV on the roof, and electrify heating, cooking and hot water in those premises, we raise the amperage on that secondary.

Not only do we raise the amperage, but we do it for longer each day, reducing the cooling time available.

So what?

In some premises, half of the current total system losses for that premise (transmission + distribution + secondary) are in the secondary. Half!

As we increase the demand for power (in either direction exporting or importing) those losses will increase further.

Is it time to address right sizing the secondary to reduce losses?

OBTW most European style system have longer secondaries, so this is not just a US problem.