Home / Comparisons / Switchyard and Substation, What Is Different
Switchyard and Substation, What Is Different
People use the words loosely. The real difference is whether voltage changes.
| Switchyard | Substation | |
|---|---|---|
| Transforms voltage | No | Yes, that is the point |
| Main equipment | Breakers, disconnects, bus | Transformers plus breakers and bus |
| Typical location | At a generating plant | Anywhere on the network |
| Purpose | Route and isolate circuits at one voltage | Step voltage up or down |
| Voltage level | Usually transmission, 69 kV and above | Any level, transmission down to distribution |
| Ownership | Generator or transmission operator | Utility, or the customer on large sites |
| Protection | Relays and breakers on each circuit | Relays, breakers, fuses and reclosers |
| Footprint | Large open yard | Anything from a yard to a locked cabinet |
Which you actually need
If there is no transformer, it is a switchyard. If voltage changes, it is a substation. A pad-mounted transformer is, in effect, a one unit substation in a locked box at the end of the line.
On a one line diagram the tell is simple. Draw the transformer symbol and it is a substation. If every circuit enters and leaves at the same voltage through breakers and disconnects, it is a switchyard.
This matters commercially because the two attract completely different equipment budgets and lead times. Switchyard equipment is breakers and steel. Substation equipment includes the transformer, which is the long lead item and usually the largest single line on the order.
Working from a specification that uses one of these terms loosely? Send it over and we will tell you which equipment it is actually calling for, before you order the wrong thing. Get a quote or call 786 220 2801.