How much will load change per 1% change in frequency?

When discussing how load changes with frequency, it's important to understand the concept of frequency response in power systems. A change in system frequency typically indicates a mismatch between supply and demand. In North American electric power systems, the standard frequency is 60 Hz. The rate at which load responds to changes in frequency is characterized by the system's frequency response characteristic.

For most systems, a 1% change in frequency leads to approximately a 2% change in load. This relationship arises as consumers and automated systems adjust their electricity consumption in response to frequency fluctuations. A decrease in frequency indicates that the load is consuming more electricity than what is being generated, prompting a reduction in load to stabilize the system. Conversely, an increase in frequency indicates excess generation and can lead to an increase in load.

Understanding this principle is crucial for operators and engineers in maintaining system reliability and ensuring that the grid can respond effectively to changes in demand and generation.