The Francis turbine is a type of water turbine used for generating electricity in hydroelectric power plants. It was invented by James B. Francis in the 19th century and is designed to operate efficiently with a wide range of water flow rates. The turbine consists of a runner with curved blades that convert the kinetic and potential energy of flowing water into mechanical energy. This turbine is particularly effective for medium to high head applications, making it a popular choice in many hydroelectric facilities. Its design allows for adjustable flow, which helps optimize performance and efficiency, contributing to sustainable energy production.