Brakes slow a car down. Brakes in a gas car turn the car's motion energy into heat through friction. An electric car can slow down another way too. When an electric car slows down, its motor can act as a generator and send energy to the battery. This is called regenerative braking. Regenerative braking reduces wear on an electric car's brakes.

A gas car burns its fuel inside the engine itself. The engine has pistons that move up and down. A spark plug lights the fuel. Gases from the burning fuel expand and push the piston. The transmission passes the engine's power on to the wheels. Gases go out through a tailpipe.

An electric car has an electric motor instead of a gas engine. The motor turns the wheels. The controller sets how much power goes to the motor. An electric car's motor stops when the car stops, so it does not idle. Electric motors run quietly and smoothly. An electric car has far fewer moving parts than a gas engine.

An electric car stores its energy in a rechargeable battery. It uses the battery for fuel, in place of gasoline. The car has a charge port. The port connects it to an outside power supply. The car is plugged in to charge it.

Words to know

• friction: rubbing
• generator: makes electricity
• transmission: power passer
• controller: power manager
• idle: run while stopped