When the term hybrid vehicle is used, it most often refers to a Petroleum electric hybrid vehicle. These encompass such vehicles as the Toyota Prius, Toyota Camry Hybrid, Ford Escape Hybrid, Honda Insight and others. A petroleum-electric hybrid most commonly uses internal combustion engines (generally gasoline or Diesel engines, powered by a variety of fuels) and electric batteries to power electric motors. There are many types of petroleum-electric hybrid drivetrains from Full hybrid to Mild hybrid which offer varying advantages and disadvantages.

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