An electric vehicle is a vehicle that is propelled by electric motors. This is the case for metros and usually trams, and for some trains (i.e. for some locomotives and often for multiple units), and for electric trolleybuses. Helios Prototype is the name of a solar- and fuel cell system-powered unmanned aerial vehicle. Some rocket propulsion systems use electricity, e.g. the ion thruster.
The term is used in particular for electric automobiles. The rest of the article will pertain to those.
The energy used to power the motors can be obtained from a variety of sources including fuel cells and batteries. Strictly Solar Powered passenger carrying electric cars and model cars are used only for technology-proving races.
There are a variety of battery electric vehicles that have been produced ranging from SUVs to sports cars. The chief problem with battery electric vehicles is their limited range in comparison with gasoline powered vehicles and the limited number of charge–discharge cycles provided before battery replacement is required. The problem of range could be addressed through the use of gas-electric hybrid vehicles which use an electric engine and grid-rechargeable batteries for acceleration and slow speed driving, with the ability to switch to gasoline power for cruising. A number of hybrid vehicles are being sold; however, none have these capabilities. The future of electric vehicles is dependent upon the availability of batteries with higher energy densities and longer life at reasonable cost, as all other engineering problems of motor control, power delivery, and regenerative braking have been solved. While auto manufacturers have active programs developing fuel cells which could replace batteries to power electric cars, battery electric vehicles would have an advantage over fuel cells because fuel cell cars require as much as four times more energy per unit distance than an electric car when hydrogen production energy is included (assuming both vehicles use the same electric motors, the same tires, the same rim size, have the same weight, and share aerodynamic characteristics). Battery electric vehicles also have an advantage over fuel cell electric vehicles because they do not need expensive membranes made of platinum and other rare metals in which to develop their energy, although batteries have a relatively high life–cycle cost and most have environmental disposal issues.
Electric vehicles have been noted for being more environmentally friendly than conventional internal combustion engine (ICE) automobiles. Although the power for the car still has to be generated from a source, this energy can be provided by environmentally friendly technologies such as tidal, solar, wind or hydroelectric power. In addition, electric engines are several times more efficient than an ICE because they are not limited by thermodynamic (heat difference) considerations and have no significant friction creating sliding mechanisms. Electric vehicles can also reclaim kinetic energy when braking through a regenerative process (as can hybrid vehicles). Electric vehicles can potentially last longer as their motors have one moving part and do not require the large number of pressure sealing devices of an ICE. They also often do not require a transmission, and without a transmission they do not require a clutch. Overall system efficiency may be reduced by transmission losses from electricity distribution, but this is less of a consideration if the vehicle owner adds photovoltaic power production.
Critics of electric vehicles point out that in addition to the contrast in range, the large batteries needed to store energy in the vehicles are a serious environmental hazard. These claims are often refuted by environmentalists because the batteries can be recycled with minimal environmental impact and more advanced batteries such as lithium ion and nickel metal hydride batteries might give the cars the range of conventional gas cars. Due to lack of production volume, these batteries are currently 3-4 times more expensive than conventional Lead Acid or Nickel Cadmium batteries. Firefighters and rescue personnel require special training to deal with the higher voltages encountered in electric vehicle accidents.
Critics also note that years of research have so far failed to yield economical or long-lasting batteries. In addition, battery recharge times are longer than practical in many situations. The fastest recharge times are achieved when quick charge technology is utilized, allowing charging times of under 30 minutes -- a number still not practical for refueling stations.
The greatest fans of electric vehicles are those who have obtained and used them. Owing to the fact that electric vehicles have not been promoted by the major manufactures in the United States, this is a self-selected group, so their enthusiasm may be misleading. Fans point out the following:
- Range is adequate if not the only vehicle in household or if long commutes are not required. Fans point out that most trips in non-commute vehicles are for shopping, school drop-off/pick-up, visiting, and other errands within a 10 to 20 mile (15 to 30 km) radius. Long range is simply not needed for such trips and an operating range of 30 to 40 miles (50 to 65 km) is quite sufficient.
- Fueling at home by charging batteries may be more convenient than driving to obtain liquid or gaseous fuel and both the availability and the cost of operation is predictable.
- The homeowner can install on-grid solar photovoltaic rooftop power and so produce most of the energy required for personal transportation with true zero pollution. Since the vehicles can be charged during low demand times the photovoltaics provide a larger societal benefit by helping to satisfy local peak demand, greatly reducing overall pollution and reducing transmission line loads. Additional benefits can also flow to the user through time sensitive pricing/payback schemes, significantly reducing the cost of a system that will support transportation needs. Once a commitment to producing power is made becomes an easy decision to commit to producing all household and local transportation power needs. Thus there is a societal benefit from electric vehicles beyond transportation.
- Electric vehicles are quiet. Even if not completely silent, they do not produce the low frequency rumble that can easily penetrate household walls and windows.
- Owners take pride in the non-polluting nature of their vehicles. Some point out that knowing that your vehicle is non-polluting quickly leads to a realization how stinky and noxious even modern, well tuned non-electric vehicles actually are — something that tends to be ignored when you are part of the problem.
- Some EV fans with a left of center political bias or of an extreme "green" inclination claim that when combined with household photovoltaics, electric vehicle users are not assisting (through their fuel purchases) despotic governments in oil-rich countries, nor the politically powerful companies that prepare and distribute their products, nor the politically powerful coal interests, nor the domestic politicians that serve and protect these companies and countries. Many electric vehicle owners and operators express great satisfaction in this aspect of electric vehicle use, even while acknowledging that this use can have only little effect on these matters at the present time.
- Some USA EV fans have accused the three major domestic manufactures, General Motors, Chrysler Corporation and Ford Motor Company of deliberately sabotaging their own electric vehicle efforts through several methods: failing to market, failing to produce appropriate vehicles, failing to satisfy demand, and using lease-only programs with prohibitions against end of lease purchase. By these actions they have managed to terminate their EV development and marketing programs despite operator's offers of purchase and assumption of maintenance liabililties. They also point to the Chrysler "golf cart" program as an insult to the marketplace and to mandates, accusing Chrysler of intentionally failing to produce a vehicle usable in mixed traffic conditions. The manufacturers, in their own defense, have responded that they only make what the public wants. EV fans point out that this response is the same argument used by GM to justify the intensively promoted 8 mpg 6500 lb (2,950 kg) Hummer H2 SUV. Of the various electric vehicles marketed by the "Big Three", only the General Motors EV1 (manufactured by GM) and the Th!nk City (imported and marketed by Ford) came close to being appropriate configurations for a mass market. However, at the end of their programs GM destroyed its fleet, despite offers to purchase them by their drivers. Ford's Norwegian-built "Th!nk" fleet was covered by a three-year exemption to the standard U.S. Motor Vehicle Safety laws, after which time Ford had planned to dismantle and recycle its fleet; the company was, however, persuaded by activists to not destroy its fleet but return them to Norway and sell them as used vehicles.
- Both Honda and Toyota also manufactured electric only vehicles. Honda followed the lead of the other majors and terminated their lease–only programs. Toyota offered vehicles for both sale and lease, while Ford also sold a few lead-acid battery Ranger EVs, unique among the large manufactures. While Toyota has terminated manufacture of new vehicles it continues to support those manufactured. It is actually possible to see a RAV-4 EV on the road but this is indeed a rare sight.
- There is a minor industry supporting the conversion and building of electric vehicles by hobbyists. Some designers point out that a specific type of electric vehicle offers comfort, utility and quickness, sacrificing only range. This is called a short range electric vehicle. This type may be built using high performance lead–acid batteries, but of only about half the mass that would be expected to obtain a 60 to 80 mile range. The result is a vehicle with about a thirty mile range, but when designed with appropriate weigh distribution (40/60 front to rear) does not require power steering, offers exceptional acceleration in the lower end of its operating range, is freeway capable and legal, and costs less to build and maintain. By including a manual transmission this type of vehicle can obtain both better performance and higher efficiency than the single speed types developed by the major manufactures. Unlike the converted golf carts used for neighborhood electric vehicles these may be operated on typical suburban throughways (40 to 45 MPH speed limits are typical) and can keep up with traffic typical to these roads and to the short on and off segments of freeways that are common in suburban areas.
The United States produced many electric automobiles, such as the Detroit Electric, during the early 20th century, but production dropped to insignificant numbers with the triumph of gasoline powered internal combustion engine vehicles in the 1920s.
In recent years, electric vehicles have been promoted through the use of tax credits. In California, the California Air Resources Board attempted to set a quota for the use of electric cars, but this was withdrawn after complaints by auto manufacturers that the quotas were economically unfeasible due to a lack of consumer demand. However, many believe this complaint to be unwarranted due to the claim that there were thousands waiting to purchase or lease electric cars from companies such as General Motors, Ford, and Chrysler in which these companies refused to meet that demand despite their production capability. Others note that the original electric car leases were at reduced cost and the program could not be expected to draw the high volumes required without selling or renting the cars at a financial loss. Since the California program was designed by California Air Resources Board:CARB to reduce air pollution and not to promote electric vehicles, the zero emissions requirement in California was replaced by a combination requirement of a tiny number of zero-emissions vehicles (to promote research and development) and a much larger number of partial zero-emissions vehicles (PZEVs), which is an administrative designation for an super ultra low emissions vehicle (SULEV), which emits pollution of about ten percent of that of an ordinary low emissions vehicle.
In London, electrically powered vehicles are one of the categories of vehicle exempted from the Congestion Charge. Similarily in Oslo, where EVs are also allowed to use the bus lane.
Electric vehicles were among the earliest automobiles, and before the preeminence of internal combustion vehicles, electric automobiles held many vehicle land speed and distance records in the early 1900s. They were produced by Anthony Electric, Baker Electric, Detroit Electric, and others and at one point in history out-sold gasoline-powered vehicles.
Internal combustion engines replaced electric drive with the invention of the electric starter by Cadillac. For more information on this subject, see history of the electric vehicle.
Recent or current production electric vehicles sold or leased to fleets include:
Recent prototype EVs include:
- Ford E-Ka
- Lexus EV (Featured in the film Minority Report)
- Pinanfarina Ethos II
- Renault EV Racer
- Solectria Sunrise
- Subaru Zero EV
- Suzuki EV Sport
Hobbyists and racing
Aside from production electric cars, often hobbyists build their own EVs by converting existing production cars to run on electricity. Universities such as the University of California, Irvine even go so far as to build their own custom electric or hybrid-electric cars from scratch.
Electric vehicles are also highly popular in quarter mile (400 m) racing. The National Electric Drag Racing Association regularly holds electric car races and often competes them successfully against exotics such as the Dodge Viper.
See also "http://www.driveclean.ca.gov" for an official California site on ZEVs and PZEVs. A page on this site, "http://www.driveclean.ca.gov/en/gv/vsearch/cleansearch.asp" will also list the available cars in various categories, especially informative if you are looking for an electrically powered city car (that page has no entries).