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Electric Vehicles

Electric vehicles (EVs) include cars, buses, trolleys, light-rail, subways, and bicycles. Electric vehicles include cars that are charged with current and vehicles that generate electricity or store electricity in batteries to run. They have an electric motor that turns the wheels and a battery to run the motor. As a result of the electric motor being directly connected to the wheels, EVs will consume no energy while the car is at rest or while coasting. Most electric vehicles employ regenerative braking, which allows some of the kinetic energy to be stored in the vehicle while decelerating. To accomplish this, the motor is operated as a generator providing braking torque to the wheels and recharging the traction batteries. This energy can then be used for propulsion or to power vehicle accessories.

Electric cars have a range of about 50-100 miles driving at a respectable pace before you have to recharge the batteries. It takes from 8 to 10 hours to recharge the battery and that is generally done during the night. In tests of the latest generations of electric vehicles there is an upward trend in the average miles an electric vehicle can be driven on a single charge from previous generations. Electric vehicles use lead acid, nickel cadmium, or nickel metal hydride batteries that power the motor. There has also been an annual improvement in the performance capabilities of tested electric vehicles.

Many electric cars are being designed for urban driving because they work well for the short distances, lower speeds, and stop-and-go city driving. (Top speeds are usually about 60 mph.) Most of these cars are smaller versions of regular passenger vehicles. This makes them easier to park and drive than many typical cars. They also produce no tailpipe emissions, are more efficient than cars with gasoline engines, and require less maintenance.

Hybrid electric vehicles (HEVs) have batteries to provide electric power and a small internal combustion engine usually powered by gasoline. The batteries get recharged from the gasoline or diesel engine. While braking, kinetic energy is converted into electricity and then stored in the battery. The engine shuts down completely at stoplights. HEVs have lower emissions and have twice the fuel economy of conventional vehicles.

Research is currently being done to use fuel cells that create electricity to power cars. Zero emissions would be produced throughout the entire energy cycle.