Automatic Generation Control (AGC) is a system used in power plants to maintain the balance between electricity supply and demand. It automatically adjusts the output of generators to ensure that the frequency of the electrical grid remains stable. This is crucial for preventing blackouts and ensuring reliable power delivery. AGC works by continuously monitoring the grid's frequency and the load on the system. When there is a deviation, such as an increase in demand, AGC sends signals to generators to increase or decrease their output. This helps maintain the desired frequency and ensures that the power supply meets the needs of consumers.