Helical extension springs store mechanical energy through linear extension and can release it to drive a flywheel, which smooths rotational motion for power generation. Recent patents and studies show systems using spring arrays to store potential energy and convert it via gearing into electrical power. Combining springs with flywheels leverages the spring’s energy storage and the flywheel’s kinetic energy smoothing, potentially enabling efficient mechanical-to-electrical energy conversion. However, challenges include designing effective motion conversion mechanisms and managing energy losses.