This document discusses tidal power plants and how they generate electricity from tidal energy. Tidal power plants use large barriers built across tidal passages to capture the potential energy of rising and falling tides. As the tides shift, the water height difference across the barrier is used to drive turbines connected to generators to produce electricity. The largest operational tidal power plant is the 254 MW Sihwa Lake Tidal Power Plant in South Korea. The document also outlines some advantages and disadvantages of tidal power plants such as being pollution-free but having irregular power supply.