Chemical

• Batteries are a familiar way to produce electricity from chemicals. When you connect the battery to a circuit, chemical reactions create an electric current.
  
  

Atomic

• The radioactive decay of some elements gives off radiation in the form of charged particles. This is used as electric power for deep space probes and pacemakers.
  
  

Electromagnetic

• Household electricity comes from power company generators. In a generator, a copper coil moves through a magnetic field, creating current in the coil.
  
  

Triboelectric

• When objects touch and separate, electric charges pile up in them. This is what's commonly called "static electricity," and is responsible for static cling and lightning.
  
  

Photovoltaic

• When light shines on some materials, electrons move in them. Solar, or photovoltaic, cells are made of silicon and other light-sensitive elements. As long as the sun's shining, the solar cells produce electric power.