Why Power System Frequency Fluctuates
23 January, 2026 at 10:00
Power system frequency fluctuates primarily due to a momentary imbalance between electricity generation (supply) and demand (load). When demand exceeds generation, generators slow down, causing a frequency decrease; when generation exceeds demand, they speed up, causing a frequency increase. Small fluctuations are normal and happen every second as devices switch on and off, but bigger, sudden changes can be risky and even lead to blackouts.