Distribution networks

Its job in the system

Distribution brings power from a supply substation to many individual connections. A feeder serves a group of customers, with branches and local transformers along the route. Its job combines delivery with maintaining acceptable voltage and coordinating protection across a network spread through everyday public space.

How it works

Demand is distributed unevenly in space and time. A cluster of appliances or vehicle chargers can increase current in particular equipment even when the wider grid has enough generation. Conductors and transformers therefore have local limits. A system can have an energy surplus overall and still face a constrained street-level connection.

Rooftop solar changes the traditional picture of power flowing only from a substation towards homes. When local production exceeds local use, power can flow back through parts of the distribution network. Networks and connection rules manage this with equipment design, voltage control, export limits, and other arrangements. The teaching arrows show one ordinary supply case, not every possible direction.

What it connects to

Distribution depends on upstream supply, local switchgear, and the service connection into a property. It also connects distributed generation and storage. Meter readings describe what crosses a connection over time; they do not reveal every electrical condition on the feeder.

Different places, different designs

Some networks are largely radial, with one usual supply path. Others have loops or interconnections that provide switching options. Cables may be buried or overhead. Household voltage, frequency, phases, earthing arrangements, and ownership boundaries differ by jurisdiction; the drawings intentionally avoid prescribing one local standard.