Electric Vehicles

Although electric vehicles (commonly known as EVs) are not necessarily powered by renewable energy, they can provide a good option for decreasing oil consumption in the short term and moving to renewables in the longer term. EVs use electric motors, rather than an internal combustion engine, to power the vehicle. The electricity is stored in a battery, usually either Lithium ion (Li-ion) or, less commonly, Nickel-metal Hydride (NiMH). Key advantages of EVs are low operating costs, very quiet operation, and virtually zero emissions (from the vehicle itself). EVs have very quick acceleration and electric motors operate efficiently at low speeds. EVs have several major drawbacks, however, including limited range for most vehicles, high initial cost, and lack of charging infrastructure.

The great appeal of EVs is the flexibility of sources for electricity production. Although biofuels have supplemented petroleum-derived fuels in recent years, transportation in the U.S. has depended very heavily gasoline and diesel. By shifting to electricity, EVs offer great intermediate-term promise, since electricity can be generated from an array of renewable sources. That makes EVs a good partner for renewable energy.

The most popular EVs currently are hybrid vehicles. There are a range of hybrid options, beginning with hybrids that are similar to traditional gasoline (or diesel) vehicles but with an expanded battery that powers a motor to help increase fuel efficiency. This is what most people think of when hearing that a car is a “hybrid,” though even within this category there are major differences between the amount of work done by the electric motor (as opposed to the gasoline or diesel engine). A popular example of this type of standard hybrid is the Toyota Prius. More advanced plug-in hybrid electric vehicles (sometimes called PHEVs, or simply plug-ins) are more like fully electric vehicles but with a petroleum-powered engine as a supplement. The Chevy Volt, for example, is a PHEV that uses gasoline to power a generator to create electricity to drive its electric motor when the batteries run out. Full EVs, like the Tesla Roadster and the Nissan LEAF, have only an electric motor.