Britannica Sources used in this answer

What do step-up and step-down transformers do in an electric power system?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

The science behind static electricity — electricity Explanation of static electricity and its manifestations in everyday life.

In an electric power system, transformers are essential devices that use electromagnetic induction to adjust voltage levels for efficient transmission and safe use.1

Step-up transformers: These are utilized at generating stations to increase the voltage of electric power. By raising the voltage, the system can transmit electricity over long distances while minimizing power losses caused by the resistance of transmission lines.213
Step-down transformers: These are employed at substations and near end-use locations to reduce high transmission voltages to lower, safer levels. This process makes the electricity suitable for distribution systems and the operation of low-voltage devices, such as household appliances.213

By managing these voltage changes, transformers ensure that energy can be moved efficiently from remote power plants to the consumers who rely on it.3