A substation is part of an electrical generation, transmission, and distribution system. Substations transform voltage from high to low, or the reverse, or perform any of several other important functions. From the generating station to the consumer, electric power may flow through several substations at different voltage levels.

Substations may be owned and operated by an electrical utility, or by a large industrial or commercial customer. Substations are generally unattended, relying on SCADA for remote supervision and control.