Electric Vehicles (EVs)
Electric vehicles are the least polluting mode of transportation available today. They also can operate very economically while using little or no petroleum fuel.
Do Battery-operated Electric Vehicles Pollute?
Battery-operated electrics run on electricity stored in batteries, electricity that ultimately comes from generating plants that also provide our homes with electrical power.
Battery-operated electric vehicles are sometimes referred to as “zero emission vehicles” because they do not directly pollute through tailpipe emissions, fuel evaporation, fuel refining, or fuel transport to service stations. A certain amount of pollution, however, is associated with the use of these vehicles. This comes from power plant emissions. Pollution levels from battery-operated electric vehicles remain extremely low even when these emissions are taken into account. One reason this is true is that the generators and motors used in electric vehicles are much more efficient than the powertrains of internal combustion engines. The difference is such as to make it more efficient to burn an amount of fuel in a power plant to generate electricity for an electric vehicle than to burn it directly in a vehicle’s internal combustion engine.
Adding to the efficiency of electric vehicles is the technique of regenerative braking. This involves slowing and stopping a vehicle by absorbing its energy and converting it to electricity that may be returned to the vehicle’s onboard battery. In a conventional vehicle, this energy is simply wasted as heat.
Of course, burning less fuel in going a certain distance does not necessarily make for less pollution. That depends on the efficiency of and emissions from the power plant providing the electricity. Over 95% of the fuel used to generate electrical power comes from within the U.S. in the form of coal, natural gas, nuclear power, hydropower, and renewable energy sources.
Electric vehicles turn out to be more than 90% cleaner than the cleanest conventional gasoline-powered vehicle when the electricity running them comes from clean energy sources such as natural gas, nuclear power, hydropower, or renewable fuels.
Electric vehicles remain cleaner than comparable gasoline-powered vehicles even when the electricity they use derives from polluting fuels like coal. The reasons are their high-efficiency electric powertrains and the fact that modern coal-burning generating plants produce electricity more efficiently and with fewer emissions than they did in the past.
The environmental benefits from using battery-operated electric vehicles promise to increase with time. That’s because electric generation continues getting cleaner as older, dirtier generating plants are taken out of service and replaced with newer, less polluting ones, and as pollution-free solar or wind generators come on-line.
Do Electric Vehicles Operate Differently?
Driving an electric vehicle is very similar to driving a gasoline-fueled vehicle.
Well-designed electrics can travel at the same speeds as conventional vehicles and provide similar performance capabilities.
The driving ranges of battery-operated electric vehicles typically vary from 50 to 130 miles, depending on a vehicle’s weight, its design features, and the type of battery it uses.
What battery-operated vehicles give up in range, they return in refueling convenience. Drivers can refuel a battery-operated vehicle by simply plugging it into a special recharging outlet at home. The recharging time depends on the voltage of the recharging station, the ambient air temperature, the size and type of the battery pack, and the remaining electrical energy in storage. Typically, the process takes several hours, but batteries are being developed that can be recharged more quickly.
The cost of fully recharging a battery pack varies with the rates charged by local utility companies, but generally is considerably less than the cost of an equivalent amount of gasoline.
More routine maintenance costs are less with battery-operated vehicles than their conventional counterparts, since the vehicles have fewer moving parts to service and replace.
Source: U.S. Department of Energy, EERE