steam engine (Heat → Mechanical energy) Ocean thermal power (Heat → Electrical energy) Hydroelectric dams (Gravitational potential energy → Electrical energy) Electric generator (Kinetic energy or Mechanical work → Electrical energy) Fuel cells (Chemical energy → Electrical energy) Battery (electricity) (Chemical energy → Electrical energy) Fire (Chemical energy → Heat and Light) Electric lamp (Electrical energy → Heat and Light) Microphone (Sound → Electrical energy) Wave power (Mechanical energy → Electrical energy) Windmills (Wind energy → Electrical energy or Mechanical energy) Piezoelectrics (Strain → Electrical energy) Friction (Kinetic energy → Heat) Electric heater (Electric energy → Heat) Photosynthesis (Electromagnetic radiation → Chemical energy) ATP hydrolysis (Chemical energy in adenosine triphosphate → mechanical energy) See also Chaos theory Conservation law Conservation of energy Conservation of mass Groundwater energy balance Laws of thermodynamics Noether's theorem Uncertainty principle Energy quality Thermoeconomics Energy Accounting References Further reading Energy Transfer and Transformation | Core knowledge science