230 kV is most commonly used in which layer of the grid?

• A. Transmission Systems
• B. Industrial Customer Systems
• C. Generation Systems
• D. Distribution Systems

Answer: (D)

Understanding where 230 kV fits in the grid’s layers helps explain why it’s considered part of the distribution side in this context. Voltage levels are chosen to balance how power is moved with the costs and insulation requirements of equipment. Very high voltages are used for long-distance bulk transmission, while lower voltages serve local distribution to end users. In many grids, 230 kV sits at the sub-transmission or regional distribution interface, carrying substantial bulk power from major substations toward the distribution network that feeds substations and large loads. That placement makes 230 kV a common voltage for the distribution systems layer in this framing, bridging the high-voltage backbone and the lower-voltage distribution feeders.

Generation systems typically deal with generator voltages and then step those up to transmission levels, and transmission systems often operate at voltages higher than 230 kV in many grids, with distribution systems stepping down from those high voltages to the levels used by homes and smaller industrial customers.