Compressed air car The principal disadvantages are the steps of energy conversion and transmission, because each inherently has loss. For combustion engine cars, the energy is lost when chemical energy in fossil fuels is converted by the engine to mechanical energy. For electric cars, a power plant's electricity (from whatever source) is transmitted to the car's batteries, which then transmits the electricity to the car's motor, which converts it to mechanical energy. For compressed-air cars, the power plant's electricity is transmitted to a compressor, which mechanically compresses the air into the car's tank. The car's engine then converts the compressed air to mechanical
Power-to-weight ratio engines and rockets, deliverable from heat engines to a vehicle. An electric motor uses electrical energy to provide mechanical work, usually through the interaction of a magnetic field and current-carrying conductors. By the interaction of mechanical work on an electrical conductor in a magnetic field, electrical energy can be generated. Fluids (liquid and gas) can be used to transmit and/or store energy using pressure and other fluid properties. Hydraulic (liquid) and pneumatic (gas) engines convert fluid pressure into other desirable mechanical or electrical work. Fluid pumps convert mechanical or electrical work into movement or pressure changes of a fluid, or