- Electric car
An electric car is a type of alternative fuel
carthat utilizes electric motors and motor controllers instead of an internal combustion engine(ICE). The electric power is usually derived from battery packs in the vehicle.
In general terms an electric car is a rechargeable
battery electric vehicle. Other examples of rechargeable electric vehicles are ones that store electricity in ultracapacitors, or in a flywheel. [ [http://findarticles.com/p/articles/mi_m1511/is_n8_v17/ai_18471043 Reinventing the wheel - Jack Bitterly is developing the flywheel automobile engine] ]
Vehicles using both electric motors and other types of engine are known as
hybrid electric vehicles and are not considered pure electric vehicles(EVs) because they operate in a charge-sustainingmode. Hybrid vehicles with batteries that can be charged externally to displace are called plug-in hybridelectric vehicles (PHEV), and are pure battery electric vehicles (BEVs) during their charge-depletingmode. Electric vehicles include automobiles, light trucks, and neighborhood electric vehicles.
The electric car was among some of the earliest automobiles — small electric vehicles
predatethe Otto cycle upon which Diesel ( diesel engine) and Benz ( gasolineengine) based the automobile. Between 1832 and 1839 (the exact year is uncertain), Scottish businessman Robert Anderson invented the first crude electric carriage. Professor Sibrandus Stratingh of Groningen, the Netherlands, designed the small-scale electric car, built by his assistant Christopher Becker in 1835. [ [http://www.rug.nl/museum/geschiedenis/hoogleraren/stratingh Stratingh's electric cart] ]
The improvement of the storage battery, by Frenchmen
Gaston Plantein 1865 and Camille Faure in 1881, paved the way for electric vehicles to flourish. An electric-powered two-wheel cycle was demonstrated at the World Exhibition 1867 in Paris by the Austrian inventor Franz Kravogl. France and Great Britain were the first nations to support the widespread development of electric vehicles. [Bellis, M. (2006) "The History of Electric Vehicles: The Early Years" "About.com" [http://inventors.about.com/library/weekly/aacarselectrica.htm article at inventors.about.com] accessed on 6 July 2006] In November 1881 French inventor Gustave Trouvédemonstrated a working three-wheeled automobile at the International Exhibition of Electricity in Paris. [cite book
author=Wakefield, Ernest H.
title=History of the Electric Automobile
publisher=Society of Automotive Engineers, Inc.
Just prior to 1900, before the pre-eminence of
internal combustion engines, electric automobiles held many speed and distance records. Among the most notable of these records was the breaking of the 100 km/h (60 mph) speed barrier, by Camille Jenatzyon April 29, 1899 in his 'rocket-shaped' vehicle Jamais Contente, which reached a top speed of 105.88 km/h (65.79 mph).
Electric cars, produced in the USA by Anthony Electric, Baker, Detroit,
Edison, Studebaker, and others during the early 20th century for a time out-sold gasoline-powered vehicles. Due to technological limitations and the lack of transistor-based electric technology, the top speed of these early electric vehicles was limited to about 32 km/h (20 mph). These vehicles were successfully sold as city cars to upper-class customers and were often marketed as suitable vehicles for women drivers due to their clean, quiet and easy operation. Electrics did not require hand-cranking to start.
The introduction of the
electric starterby Cadillac in 1913 simplified the task of starting the internal combustion engine, formerly difficult and sometimes dangerous. This innovation contributed to the downfall of the electric vehicle, as did the mass-produced and relatively inexpensive Ford Model T, which had been produced since 1908. [McMahon, D. (2006) "Some EV History" "Econogics, Inc." [http://www.econogics.com/ev/evhistry.htm essay at econogics.com] accessed on 5 July 2006] Internal-combustion vehicles advanced technologically, ultimately becoming more practical than — and out-performing — their electric-powered competitors.
Electric vehicles became popular for some limited range applications. Forklifts were EVs when they were introduced in 1923 by Yale [http://www.yale.com/ygl_history.asp?language=ENGLISH] ; many battery electric fork lifts are still produced. Electric golf carts have been available for many years, including early models by Lektra in 1954. [http://www.lektro.com/about_history.asp] Their popularity led to their use as
neighborhood electric vehicles; larger versions are becoming popular and increasingly ruled "street legal".
By the late 1930s, the electric automobile industry had completely disappeared, with battery-electric traction being limited to niche applications, such as certain industrial vehicles. A thorough examination into the social and technological reasons for the failure of electric cars is to be found in "Taking Charge: The Electric Automobile in America" [http://www.amazon.com/dp/1588340767] by
Michael Brian Schiffer.
Battery powered electric concept cars continued to appear, such as the
Scottish Aviation Scamp(1965),cite journal |last=Carr |first=Richard |date=July 1, 1966 |title=In search of the town car
journal=Design |issue=211 |pages=29-37 |publisher=Council of Industrial Design] the
Enfield 8000(1966) [cite book |title=The Electric Car |author=Michael Hereward Westbrook |publisher=IET |year=2001 |isbn=0852960131] and the General Motors "Electrovair" (1966) and "Electrovette" (1976). At the 1990 Los Angeles Auto Show, GM President Roger Smith unveiled the "Impact" electric car, the precursor to the EV1, promising that GM would build electric cars for the public. Nine months later, the California Air Resources Board (CARB) mandated electric car sales by major automakers. In response, makers developed EVs including the Chrysler TEVan, Ford Ranger EV pickup truck, GM EV1 and S10 EV pickup, Honda EV Plus hatchback, Nissan lithium-battery Altra EV miniwagon and Toyota RAV4 EV. Automakers refused to properly promote or sell their EVs, allowed consumers to drive them only by closed-end lease and, along with oil groups, fought the mandate.
Chrysler, Toyota and some GM dealers sued in Federal court; California soon neutered its ZEV Mandate. After public protests by EV drivers' groups upset by the repossession of their EVs, Toyota offered the last 328 RAV4-EVs for sale to the general public during six months (ending on November 22, 2002). All other electric cars, with minor exceptions, were withdrawn from the market and destroyed by their manufacturers. To its credit, Toyota not only supports the 328 Toyota RAV4-EV in the hands of the general public, still all running at this date, but also supports hundreds in fleet usage. From time to time, Toyota RAV4-EVs come up for sale on the used market and command prices sometimes over 60 thousand dollars. These are highly prized by solar homeowners, who charge their cars from their solar electric rooftop systems.
Present and future
As of July, 2006, there were between 60,000 and 76,000 low-speed, battery powered vehicles in use in the US, up from about 56,000 in 2004, according to Electric Drive Transportation Association estimates.Saranow, J. (
July 27, 2006) "The Electric Car Gets Some Muscle" "The Wall Street Journal," pp. D1-2.] There are now over 100,000 NEVs on US streets.
In 1994, REVA Electric Car Company Private Ltd. was established in
Bangalore, India, as a joint venture between the Maini Group India and AEV LLC, California USA, to manufacture environment-friendly and cost-effective electric vehicles. After seven years of R&D, it launched the REVA, India's first Electric Vehicle, in June 2001. The REVA is currently commercialized in India, in the UK (since 2003), and in several other European countries (including Cyprus and Greece, Belgium, Germany, Spain Norway, and Malta). In most countries the REVAis classified as an electric quadricycle, while in the US it is allowed only as neighborhood electric vehiclewith reduced top speed. More REVAs have been produced than any other currently selling electric car.
In the summer of 2003, Martin Eberhard and Marc Tarpenning founded
Tesla Motorsin San Carlos, California. In 2006, a prototype of the Tesla Roadsterwas unveiled. Production delivery was originally planned for October 2007 and then delayed, in September 2007, until the first calendar quarter of 2008. Series production of the car began on March 17, 2008cite web
title=We have begun regular production of the Tesla Roadster
March 17, 2008
accessdate=2008-03-20] The Roadster uses
Lithium-Ionbatteries rather than the lead-acid batteries which had previously been predominant in small-maker BEVs. The vehicle uses 6831 Li-ion batteries to travel 394 km (245 mi) per charge, an equivalent fuel efficiency of 1.74 L/100 km (135 mpg U.S.), yet accelerates from 0-100 km/h in under 4 seconds on its way to a top speed of 210 km/h (135 mph). The company announced that production of the Roadster had officially begun on March 17th. The first Tesla was delivered on February 1, 2008.
In December, 2007, Fortune reported Fact|date=May 2008 on eleven new companies planning to offer highway-capable electric cars within a few years.
Aptera Motorsplans to sell both electric and hybrid versions of its Typ-1 in late 2008. Mitsubishi Motorswill sell its iMiev EV beginning in 2009. Fact|date=May 2008
Miles Electric Vehiclesannounced that it would produce a highway-speed all-electric sedan named the XS500. The company anticipates that the XS500 will be available for sale in the U.S. in early 2009. The XS500 uses Li-Ionbatteries. [cite web |author=Rubin, Miles |title=XS500 |url=http://www.milesev.com |accessdate=2008-04-15 ] [cite web |author=Hargreaves, Steve |title=XS500 |url=http://money.cnn.com/2007/08/13/autos/electric_car/index.htm |accessdate=2007-08-13 ]
In early 2008,
Dodgeannounced an electric concept carcalled Dodge Zeo. [http://www.dodge.com/en/autoshow/concept_vehicles/zeo/] While there are no official release dates or prices, they say it will be affordable to the average American. Fact|date=May 2008
In May 2008
Nissan Motor Companyannounced plans to sell an electric car in the U.S. and Japan by 2010. Nissan's chief executive, Carlos Ghosnsaid they envisioned a broad range of electric vehicles, starting with small cars. [http://www.nytimes.com/2008/05/13/business/13auto.html]
Other automakers like
Fuji Heavy Industriesare testing versions of electric cars, and General Motorsand Toyotaare working on battery-powered vehicles that have small gasoline engines for recharging.
British Columbiais the only place where you can drive an LSV electric car, although it also requires low speed warning marking and flashing lights. Quebecis allowing LSVs in a three year pilot project. These cars will not be allowed on the highway, but will be allowed on inter city streets. See ZENN#Legalization in Canada
Shai Agassihas reached agreements with Renault-Nissan and the Israeli government for a plan called Project Better Placeto install recharging and battery replacement stations nationwide and put 100,000 electric cars on the roads beginning in 2011. Israel is considered a practical choice for the first large-scale use of electric vehicles because 90 percent of car owners drive less than 70 kilometers per day and the major cities are fewer than 150 kilometers apart. [ Zvi Hellman, "A Dream Green Car," Jerusalem Report, Feb. 18, 2008]
Portugalhas also reached agreements with French car maker Renaultand its Japanese partner Nissanto boost the use of electric cars by creating a national recharging network.The aim is to make Portugal, just like Israel, one of the first countries to offer drivers the possibility of nationwide charging stations.cite news | title=Euronews | url=http://www.euronews.net/en/article/09/07/2008/electric-car-recharging-deal-for-portugal/ | date= 2008-07-09| accessdate=2008-07-19
Since the late 1980s, electric vehicles have been promoted in the US through the use of tax credits. Electric cars are the most common form of what is defined by the
California Air Resources Board(CARB) as zero emission vehicle(ZEV) passenger automobiles, because they produce no emissions while being driven. The CARB had set progressive quotas for sales of ZEVs, but most were withdrawn after lobbying and a lawsuit by auto manufacturers complaining that EVs were economically infeasible due to an alleged "lack of consumer demand". Most of these lobbying influences are shown in a documentary, called Who Killed the Electric Car?.
The California program was designed by the CARB to reduce air pollution and not specifically to promote electric vehicles. Under pressure from various manufactures, CARB replaced the zero emissions requirement with a combined requirement of a very small number of ZEVs to promote research and development, and a much larger number of
partial zero-emissions vehicles (PZEVs), an administrative designation for a "super ultra low emissions vehicle" ( SULEV), which emit about ten percent of the pollution of ordinary low emissions vehicles and are also certified for zero evaporative emissions. While effective in reaching the air pollution goals projected for the zero emissions requirement, the market effect was to permit the major manufacturers to quickly terminate their electric car programs and crush the vehicles.
The following chart and table are based on Department of Energy tables on [http://www.eia.doe.gov/cneaf/alternate/page/atftables/afvtransfuel_II.html Alternatives to Traditional Transportation Fuels 2005] , from table V1 and from the Historical Data. Figures for electric vehicles include Low-Speed Vehicles (LSVs), which are "four-wheeled motor vehicles whose top speed is between 20 and 25 miles per hour [32 to 40 km/h] ...to be used in residential areas, planned communities, industrial sites, and other areas with low density traffic, and low-speed zones." [Hendrickson, Gail, and Kelly Ross. May 2005. [http://www.ase.org/images/lib/transportation/Alliance_Transportation_Handbook.pdf "The Drive to Efficient Transportation"] ,
Alliance to Save Energy, p. 36. Retrieved on 2007- 08-30.] LSVs, more commonly known as neighborhood electric vehicles (NEVs), were defined in 1998 by the National Highway Traffic Safety Administration's "Federal Motor Vehicle Safety Standard No. 500", which required safety features such as windshields and seat belts, but not doors or side walls. [1999. [http://www.capitol.hawaii.gov/session1999/acts/Act262_sb700.htm "Low-Speed Vehicles,"] The Senate, State of Hawaii, p. 3. Retrieved on 2007- 08-30.] [ [http://www1.eere.energy.gov/vehiclesandfuels/avta/light_duty/nev/index.html "Advanced Vehicle Testing Activity: Neighborhood Electric Vehicles."] (Website). U.S. Department of Energy, Energy Efficiency and Renewable Energy. Retrieved on 2007- 08-30.]
;Cars capable of at least 80 km/h
Relation with hybrid vehicles
Vehicles using both electric motors and Internal Combustion Engines are examples of
hybrid vehicles, and are not considered pure electric vehicles (also called all-electric vehicles) because they operate in a charge-sustainingmode. Hybrid vehicles with batteries that can be charged externally to displace some or all of their ICE power and gasolinefuel are called plug-in hybridelectric vehicles (PHEV), and are pure EVs during their charge-depletingmode. The coming Chevrolet Voltis of this type. If batteries cannot be charged externally, the vehicles are called regular hybrids.
Comparison with internal combustion vehicles
Batteries are usually the most expensive component of electric cars, though the price per
kilowatt-hourof energy capacity has fallen in recent years for the more recently introduced technologies such as lithium-ionand lithium-polymer, as would be expected for any new technology. Older technologies such as lead-acid have become more expensive due to increase in materials cost, particularly lead, driven by demand for use in powered bicycles (particularly in Chinaand India) and in uninterruptible power supplies to support small computer systems. Since the late 1990s, advances in battery technologieshave been driven by skyrocketing demand for laptopcomputers and mobile phones, with consumer demand for more features, larger, brighter displays, and longer battery time driving research and development in the field. The electric vehicle marketplace has reaped the benefits of these advances, but the cost per unit of energy capacity still favours older, heavier, less efficient technologies.
Some batteries can be leased or rented instead of bought (see
Think Nordic). In 1947, in Nissan's first electric car, the batteries were removable so that they could be replaced at filling stations with fully charged ones.
Electric car operating costs can be directly compared to the equivalent operating costs of a gasoline-powered vehicle. A litre of gasoline contains about 8.9 kW·h of energy.cite paper
author = U.S. Department of Energy (DOE)
title = Federal Register Vol. 64 No. 113
publisher = U.S. GPO
url = http://frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=2000_register&docid=00-14446-filed.pdf
accessdate = 2006-09-22] To calculate the cost of the electrical equivalent of a liter of gasoline, multiply the utility cost per kW·h by 8.9. Because automotive internal combustion engines are only about 20% efficient, then at most 20% of the total energy in that liter of gasoline is ever put to use. [ [http://mb-soft.com/public2/engine.html Physics in an automotive engine] ]
A car powered by an internal combustion engine at 20% efficiency, getting 8 L/100 km (30 mpg), will require (8.9*8)*0.20 = 14.2 kW·h/100 km. At a cost of $1/L, 8 L/100 km is $8 per 100 km. A battery electric version of that same car with a charge/discharge efficiency of 81%, and charged at a cost of $0.10 for kW·h would cost (14.2/0.81)*0.10 = $1.75 per 100 km, or would be paying the equivalent of $0.22/L. The Tesla uses about 13 kW·h/100 km, the EV1 used about 11 kW·h/100 km. [ [http://www1.eere.energy.gov/vehiclesandfuels/avta/pdfs/fsev/eva_results/ev1_eva.pdf 1999 General Motors EV1 constant speed @ 60 mph] ]
Servicing costs should be lower for an electric car. The movie "
Who Killed the Electric Car" shows a comparison between the parts that require replacement in a gasoline powered car and the EV1 (none), stating that they bring the cars in every 5,000 miles, rotate the tires, fill the windshield washer fluid and send them back out again. Even brakes require less maintenance because of the regenerative braking, the same as with a hybrid.
Electric cars using lead-acid batteries require replacement of the battery pack on a regular basis, while internal combustion engines can last the life of the vehicle, with routine repairs. Lithium-ion and NiMH batteries typically last the life of the vehicle. No Toyota Prius has ever needed its NiMH battery replaced from wear and tear. [ [http://www.hybridexperience.ca/Reliability.htm Reliability] "We have lab data showing the equivalent of 180,000 miles with no deterioration and expect it to last the life of the vehicle." Statement from Toyota Retrieved 15 August 2008]
An electric car's efficiency is affected by its charging and discharging efficiencies. A typical charging cycle is about 85% efficientFact|date=August 2008, and the discharge cycle converting electricity into mechanical power is about 95% efficient, resulting in 81% of each kW·h is put to use. The electricity generating system in the USA loses 9.5% of the power transmitted between the power station and the socket, and the power stations are 33% efficient in turning the calorific value of fuel at the powerstation to electrical power [ [http://www.energetics.com/gridworks/grid.html Overview of the Electric Grid] retrieved 15 August 2008] . Overall this results in an efficiency of 0.81*0.3=24.2% from fuel in to the power station, to power into the motor of the EV.
Production and conversion electric cars typically use 10 to 23 kW·h/100 km (0.17 to 0.37 kW·h/mi). [Idaho National Laboratory (2006) "Full Size Electric Vehicles" "Advanced Vehicle Testing Activity" [http://avt.inel.gov/fsev.html reports at avt.inel.gov] accessed
5 July 2006] [Idaho National Laboratory (2006) "1999 General Motors EV1 with NiMH: Performance Statistics" "Electric Transportation Applications" [http://avt.inel.gov/pdf/fsev/eva/ev1_eva.pdf info sheets at inel.gov] accessed 5 July 2006] Approximately 20% of this power consumption is due to inefficiencies in charging the batteries. Tesla Motors indicates that the well to wheels [ [http://www.teslamotors.com/efficiency/well_to_wheel.php Tesla Motors - well-to-wheel ] ] energy consumption of their li-ion powered vehicle is 10.9 kW·h/100 km (0.176 kW·h/mi). The US fleet average of 10 L/100 km (23 mpg US) of gasolineis equivalent to 96 kW·h/100 km (1.58 kW·h/mi), assuming 100% efficiency, and the 3.4 L/100 km (70 mpg US) Honda Insightuses 32 kW·h/100 km (0.52 kW·h/mi) (assuming 9.6 kW·h per liter of gasoline and 100% efficiency), so hybrid electric vehicles are relatively energy efficient, and battery electric vehicles are much more energy efficient.
Carbon dioxide emissions
While electric cars are considered zero-emission-at-tailpipe-vehicles, they cause an increase in electrical generation needs. Generating electricity and providing liquid fuels for vehicles are different categories of the energy economy, with different inefficiencies and environmental harms. According to the Electric Vehicle Association of Canada, (who sell electric vehicles) [ PDFlink|1= [http://www.asecert.org/Template.cfm?Section=Clean_Fuels_Clean_Vehicle_Technology1&Template=/ContentManagement/ContentDisplay.cfm&ContentFileID=609 Alternate Fuel Technology - Battery Electric Vehicles] |2=245 KB] CO2 and other
greenhouse gasemissions are minimal for electric cars powered from sustainable electricity sources (for example, by solar energy) or for internal combustion engine cars that are run on renewable fuels such as biodiesel.
If the object of the exercise in looking at alternatives to conventional vehicles is to reduce CO2 emissions, then that has to mean using the most carbon-efficient vehicle you can buy. For the "average" US grid, currently a diesel is better than an EV. Most electricity generation in the United States is from fossil sources, and a lot of that is from coal, according to the U.S. Department of Energy. [http://www.energetics.com/gridworks/grid.html Overview of the Electric Grid] . U.S. Department of Energy. Retrieved
2008-08-06.] Coal is more carbon-intensive than oil. Overall average efficiency from US power plants (33% efficient) to point of use (transmission loss 9.5%), (US DOE figures) is 29.87% . Accepting 90% efficiency for the electric vehicle gives us a figure of only 26.88% overall efficiency. That is lower than the efficiency of an internal combustion engine(Petrol/Gasoline 30% efficient, Diesel engines 45% efficient - Volvo figures). [ [http://www.volvo.com/group/global/en-gb/Volvo+Group/ourvalues/environment/products/dieselengines.htm Diesel engines - Products : Volvo Group - Global] . Retrieved 2008-08-06.] The actual result depends on different refining and transportation costs getting fuel to a car versus a power plant. Diesel engines can also easily run on renewable fuels, biodiesel, vegetable oil fuel, with no loss of efficiency. Using fossil based grid electricity entirely negates the in vehicle efficiency advantages of electric cars. The major potential benefit of electric cars is to allow diverse renewable electricity sources to fuel cars. A modern TDI PD or common rail type diesel engined vehicle, is almost twice efficient when using fossil diesel than an EV running on grid electricity which is mostly from fossil fuel. It can also run on renewable waste vegetable oil fuel, which is viewed as carbon neutral, or low carbon impact if processed into biodiesel, but controversial if new oil is used, because biofuels have been blamed for higher world food prices, (particularly US bio-ethanol) and increased rain forest depletion to grow palm oil. As well as waste oil, new vegetable oil fuels from algae, and forestry waste being piloted in Finland with Nokia venture capital, are new renewable diesel engine fuel sources that are coming on stream. Electric vehicles did not win the US 'Tour de Sol' competition for greenest car, a VW TDI running on Waste Vegetable Oil didFact|date=August 2008.
The use of solar, wind, nuclear electric generation along with carbon capture for fossil fuel powered plants means that in the long run, electric vehicles will produce less carbon dioxide over their life time since it is impractical to reduce carbon dioxide at the tailpipe of diesel/bio fueled cars. Based on GREET simulations, electric cars can achieve up to 100% reductions with renewables electric generation vs 77% will B100 (100% bio-diesel car). Of course at present only 32% reductions of carbon dioxide is available for electric cars with current US Grid due to heavy fossil fuel use and inefficiencies. [http://www.nesea.org/transportation/info/documents/Transportation_Climate_Change.pdf ] [http://www.transportation.anl.gov/modeling_simulation/GREET/publications.html]
Ontario Medical Associationannounced that smog is responsible for an estimated 9,500 premature deaths in the province each year [ [http://wheels.ca/reviews/article/256058 $3.83 to power hybrid plug-in for 6 days ] ] . Electric cars or plug-in hybrids, especially in emission-free electric mode, could vastly reduce this number.
Range vs cruising speed
The trade-off for range against cruising speed is well known for IC vehicles, typically a cruising speed of around 50 mph is near-optimal, although for specific cars it could fall as low as 25 mph, or as high as 60 mph.
For electric vehicles the equation is less complex, and maximum range is achieved at comparatively low speeds.
Although some electric vehicles have very small motors, convert|15|kW|abbr=on or less and therefore have modest acceleration, the relatively constant torque of an electric motor even at very low speeds tends to increase the acceleration performance of an electric vehicle for the same rated motor power. Another early solution was
American Motors’ experimental Amitronpiggyback system of batteries with one type designed for sustained speeds while a different set boosted acceleration when needed.
Electric vehicles can also utilize a direct motor-to-wheel configuration which increases the amount of available power. Having multiple motors connected directly to the wheels allows for each of the wheels to be used for both propulsion and as braking systems, thereby increasing
traction. In some cases, the motor can be housed directly in the wheel, such as in the Whispering Wheeldesign, which lowers the vehicle's center of gravityand reduces the number of moving parts. When not fitted with an axle, differential, or transmission, electric vehicles have less drivetrain rotational inertia.
A gearless or single gear design in some EVs eliminates the need for gear shifting, giving such vehicles both smoother acceleration and smoother braking. Because the torque of an electric motor is a function of current, not rotational speed, electric vehicles have a high torque over a larger range of speeds during acceleration, as compared to an internal combustion engine. As there is no delay in developing torque in an EV, EV drivers report generally high satisfaction with acceleration. For example, the
Venturi Fetishdelivers supercaracceleration despite a relatively modest convert|220|kW, and a top speed of around 160 km/h. Some DC motor-equipped drag racer EVs, have simple two-speed transmissions to improve top speed [Hedlund, R. (2006) "The 100 Mile Per Hour Club" "National Electric Drag Racing Association" [http://nedra.com/100mph_club.html list at nedra.com] accessed 5 July 2006] [Hedlund, R. (2006) "The 125 Mile Per Hour Club" "National Electric Drag Racing Association" [http://nedra.com/125mph_club.html list at nedra.com] accessed 5 July 2006] . The Tesla Roadsterprototype can reach convert|100|km/h|mi/h|abbr=on in 4 seconds with a motor rated at convert|185|kW|abbr=on.
The key to attaining acceptable range with an electric car is to reduce the power required to drive the car, so far as is practical. This pushes the design towards low weight. In a collision the occupants of a heavy vehicle will, on average, suffer fewer and less serious injuries than the occupants of a lighter vehicle [ [http://www.nhtsa.dot.gov/cars/rules/regrev/evaluate/pdf/809662.pdf] ] . An accident in a 2000 lb (900 kg) vehicle will on average cause about 50% more injuries to its occupants than a 3000 lb (1350 kg) vehicle [ [http://www.insure.com/articles/carinsurance/2003-models.html The safest cars of 2003] ] Electric cars use
low rolling resistance tires, which typically offer less grip than normal tires [http://www.consumerreports.org/cro/cars/tires-auto-parts/tires/low-rolling-resistance-tires-8-06/overview/0608_low-rolling-resistance-tires_ov.htm] [http://horsepowersports.com/low-rolling-resistance-tires-save-gas/] [http://www.conti-online.com/generator/www/com/en/continental/portal/themes/press_services/press_releases/safety/pr_2007_11_12_eu_vorgaben_en.html] . The weight (and price) of safety systems such as airbags, ABS and ESC may encourage manufacturers not to include them.
Using regenerative braking, a feature which is present on many electric and hybrid vehicles, a significant portion of the energy expended during acceleration may be recovered during braking, increasing the efficiency of the vehicle. [ [http://www.nabble.com/Re%3A-Why-doesn%27t-regen-work-with-DC-p12391827s25542.html Nabble - Re: Why doesn't regen work with DC ] ] [ [http://www.brusa.biz/applications/e_mini_evergreen.htm BRUSA > Applications ] ]
Rechargeable batteries used in electric vehicles include lead-acid ("flooded" and
VRLA), NiCd, nickel metal hydride, lithium ion, Li-ion polymer, and, less commonly, zinc-air and molten salt batteries. The amount of electricity stored in batteries is measured in ampere hours or in coulombs, with the total energy often measured in watt hours.
Historically, EVs and PHEVs have had issues with high battery costs, limited travel distance between battery recharging, charging time, and battery lifespan, which have limited widespread adoption. Ongoing
battery technology advancementshave addressed many of these problems; many models have recently been prototyped, and a handful of future production models have been announced. Toyota, Honda, Ford and General Motors all produced electric cars in the 1990s in order to comply with the California Air Resources Board's Zero Emission Vehicle Mandate. The major US automobile manufacturers have been accused of deliberately sabotaging their electric vehicle production efforts."The Death and Rebirth of the Electric Auto" Hari Heath. The Idaho Observer Vol 8, No. 26, Sept, 21, 2006.] [http://WhoKilledTheElectricCar.com Who killed the electric car?(website)] ]
Batteries in BEVs must be periodically recharged (see also Replacing, below).BEVs most commonly charge from the
power grid(at home or using a street or shop recharging point), which is in turn generated from a variety of domestic resources; such as coal, hydroelectricity, nuclear and others. Home power such as roof top photovoltaicsolar cell panels, micro hydroor wind may also be used and are promoted because of concerns regarding global warming.
Charging time is limited primarily by the capacity of the
gridconnection. A normal household outletis between 1.5 kilowatts (in the US, Canada, Japan, and other countries with 110 voltsupply) to 3 kilowatts (in countries with 240 V supply). The main connection to a house might be able to sustain 10 kilowatts, and special wiring can be installed to use this. At this higher power level charging even a small, 7 kilowatt-hour (22–45 km) pack, would probably require one hour. This is small compared to the effective power delivery rate of an average petrol pump, about 5,000 kilowatts. Even if the supply power can be increased, most batteries do not accept charge at greater than their charge rate ("1"C"), because high charge rate has adverse effect on the discharge capacities of batteries. [ [http://batteryuniversity.com/partone-5A.htm The high-power lithium-ion ] ]
In 1995, some
charging stations charged BEVs in one hour. In November 1997, Ford purchased a fast-charge system produced by AeroVironmentcalled "PosiCharge" for testing its fleets of Ranger EVs, which charged their lead-acid batteries in between six and fifteen minutes. In February 1998, General Motors announced a version of its " Magne Charge" system which could recharge NiMH batteries in about ten minutes, providing a range of sixty to one hundred miles. [Anderson, C.D. and Anderson, J. (2005) "New Charging Systems" "Electric and Hybrid Cars: a History" (North Carolina: McFarland & Co., Inc.) ISBN 0-7864-1872-9, p. 121.]
handhelddevice battery designs by Toshibawere claimed to be able to accept an 80% charge in as little as 60 seconds. [Toshiba Corporation (2005) "Toshiba's New Rechargeable Lithium-Ion Battery Recharges in Only One Minute" [http://www.toshiba.co.jp/about/press/2005_03/pr2901.htm press release at toshiba.co.jp] accessed 5 July 2006] Scaling this specific powercharacteristic up to the same 7 kilowatt-hour EV pack would result in the need for a peak of 340 kilowatts of power from some source for those 60 seconds. It is not clear that such batteries will work directly in BEVs as heat build-up may make them unsafe.
Altairnano's NanoSafebatteries are rechargeable in several minutes, versus hours required for other rechargeable batteries.Fact|date=August 2007 A NanoSafe cell can be charged to around 95% charge capacity in approximately 10 minutes.Fact|date=August 2007
Most people do not always require fast recharging because they have enough time, 30 minutes to six hours (depending on discharge level) during the work day or overnight to recharge. As the charging does not require attention it takes a few seconds for an owner to plug in and unplug their vehicle much like a cell phone. Many BEV drivers prefer recharging at home, avoiding the inconvenience of visiting a
fuel station. Some workplaces provide special parking bays for electric vehicles with chargers provided - sometimes powered by solar panels. In colder areas such as Minnesota and Canada there already exists some infrastructure for public power outlets, in parking garages and at parking meters, provided primarily for engine pre-heating.Fact|date=August 2008
The charging power can be connected to the car in two ways (electric coupling). The first is a direct electrical connection known as
conductive coupling. This might be as simple as a mainslead into a weatherproof socket through special high capacity cables with connectors to protect the user from high voltages. The second approach is known as inductive charging. A special 'paddle' is inserted into a slot on the car. The paddle is one winding of a transformer, while the other is built into the car. When the paddle is inserted it completes a magnetic circuit which provides power to the battery pack.In one inductive charging system [http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JAPIAU00009900000808R902000001&idtype=cvips&gifs=yes] , one winding is attached to the underside of the car, and the other stays on the floor of the garage.
The major advantage of the inductive approach is that there is no possibility of
electric shockas there are no exposed conductors, although interlocks, special connectors and ground fault detectors can make conductive coupling nearly as safe. Inductive charging can also reduce vehicle weight, by moving more charging components offboard. [http://www.theautochannel.com/news/press/date/19981123/press000865.html "Car Companies' Head-on Competition In Electric Vehicle Charging."] (Website). "The Auto Channel", 1998-11-24. Retrieved on 2007-08-21.] However there is no reason that conductive coupling equipment cannot take advantage of the same concept. Conductive coupling equipment is lower in cost and much more efficient due to a vastly lower component count.Fact|date=August 2007 An inductive charging proponent from Toyota contended in 1998 that overall cost differences were minimal, while a conductive charging proponent from Ford contended that conductive charging was more cost efficient.
Travel range before recharging and trailers
The range of an electric car depends on the number and type of batteries used, and the performance demands of the driver. The weight and type of vehicle also have an impact just as they do on the mileage of
traditional vehicles. Electric vehicle conversions depends on the battery type:
* Lead-acid batteries are the most available and inexpensive. Such conversions generally have a range of 30 to 80 km (20 to 50 mi). Production EVs with lead-acid batteries are capable of up to 130 km (80 mi) per charge.
NiMHbatteries have higher energy density and may deliver up to 200 km (120 mi) of range.
lithium-ion battery-equipped EVs provide 400–500 km (250–300 mi) of range per charge. [Mitchell, T. (2003) "AC Propulsion Debuts tzero with LiIon Battery" "AC Propulsion, Inc." [http://www.acpropulsion.com/LiIon_tzero_release.pdf press release at acpropulsion.com] accessed 5 July 2006] Lithium is also less expensive than nickel. [ [http://www.reuters.com/article/environmentNews/idUSL2055095620070621?sp=true Lithium batteries power hybrid cars of future] accessed 22 June 2007]
Finding the economic balance of range versus performance, battery capacity versus weight, and battery type versus cost challenges every EV manufacturer.
With an AC system
regenerative brakingcan extend range by up to 50% under extreme traffic conditions without complete stopping. Otherwise, the range is extended by about 10 to 15% in city driving, and only negligibly in highway driving, depending upon terrain.
BEVs (including buses and trucks) can also use
genset trailers and pusher trailers in order to extend their range when desired without the additional weight during normal short range use. Discharged battery set trailers can be replaced by recharged ones along a route. If rented then maintenance costs can be deferred to the agency.
Such BEVs can become
Hybrid vehicles depending on the trailer and car types of energy and powertrain.
An alternative to recharging is to exchange drained or nearly drained batteries (or
battery range extender modules) with fully charged batteries.
Zinc-bromine flow batteries or Vanadium redox batteries can be re-filled, instead of recharged, saving time. The depleted electrolyte can be recharged at the point of exchange, or taken away to a remote station.
V2G: uploading and grid buffering
Smart gridallows BEVs to provide power to the grid, specifically:
peak loadperiods, when the cost of electricity can be very high. These vehicles can then be recharged during off-peakhours at cheaper rates while helping to absorb excess night time generation. Here the vehicles serve as a distributed battery storage system to buffer power.
*During blackouts, as an emergency backup supply.
Individual batteries are usually arranged into large
battery packs of various voltageand ampere-hourcapacity products to give the required energy capacity. Battery life should be considered when calculating the extended cost of ownership, as all batteries eventually wear out and must be replaced. The rate at which they expire depends on a number of factors.
The depth of discharge (DOD) is the recommended proportion of the total available energy storage for which that battery will achieve its rated cycles. Deep cycle lead-acid batteries generally should not be discharged below 80% capacity. More modern formulations can survive deeper cycles.
In real world use, some fleet
Toyota RAV4 EVs, using NiMHbatteries, will exceed 160 000 km (100,000 mi), and have had little degradation in their daily range. [Knipe, TJ "et al." (2003) "100,000-Mile Evaluation of the Toyota RAV4 EV" "Southern California Edison, Electric Vehicle Technical Center" [http://www.evchargernews.com/miscfiles/sce-rav4ev-100k.pdf report at evchargernews.com] accessed on 5 July 2006] Quoting that report's concluding assessment:
quote|The five-vehicle test is demonstrating the long-term durability of Nickel Metal Hydride batteries and electric drive trains. Only slight performance degradation has been observed to-date on four out of five vehicles.... EVTC test data provide strong evidence that all five vehicles will exceed the convert|100000|mi|km|sing=on mark. SCE’s positive experience points to the very strong likelihood of a 130,000 to convert|150000|mi|km|sing=on Nickel Metal Hydride battery and drive-train operational life. EVs can therefore match or exceed the lifecycle miles of comparable internal combustion engine vehicles.
In June 2003 the 320 RAV4 EVs of the SCE fleet were used primarily by meter readers, service managers, field representatives, service planners and mail handlers, and for security patrols and carpools. In five years of operation, the RAV4 EV fleet had logged more than 6.9 million miles, eliminating about 830 tons of air pollutants, and preventing more than 3,700 tons of tailpipe carbon dioxide emissions. Given the successful operation of its EVs to-date, SCE plans to continue using them well after they all log 100,000-miles.
Jay Leno's 1909 Baker Electric (see Baker Motor Vehicle) still operates on its original Edison cells. Battery replacement costs of BEVs may be partially or fully offset by the elimination of certain regular maintenance, such as oil and filter changes required for ICEVs, and by the greater reliability of BEVs due to their fewer moving parts. They also do away with many other parts that normally require servicing and maintenance in a regular car, such as on the gearbox, cooling system, and engine tuning. And by the time batteries do finally need definitive replacement, they can be replaced with later generation ones which may offer better performance characteristics, in the same way one might replace an old laptop battery.
The safety issues of battery electric vehicles are largely dealt with by the international standard
ISO6469. This document is divided in three parts dealing with specific issues:
*On-board electrical energy storage, i.e. the battery
*Functional safety means and protection against failures
*Protection of persons against electrical hazards.
Firefighters and rescue personnel receive special training to deal with the higher voltages and chemicals encountered in electric and hybrid electric vehicle accidents. While BEV accidents may present unusual problems, such as fires and fumes resulting from rapid battery discharge, there is apparently no available information regarding whether they are inherently more or less dangerous than gasoline or diesel internal combustion vehicles which carry flammable fuels.
The future of battery electric vehicles depends primarily upon the cost and availability of batteries with high energy densities, power density, and long life, as all other aspects such as motors, motor controllers, and chargers are fairly mature and cost-competitive with internal combustion engine components.
Li-ion, Li-poly and zinc-air batteries have demonstrated energy densities high enough to deliver range and recharge times comparable to conventional vehicles.
Bolloré, a French automotive parts group, developed a concept car, called the Bluecar, using Lithium metal polymer batteries developed by a subsidiary, Batscap. It had a range of 250 km and top speed of 125 km/h. [http://www.batscap.com/actualites/communiques/BlueCar_technic-04-2007.pdf ("Bluecar") document]
The cathodes of early 2007 lithium-ion batteries are made from lithium-cobalt metal oxide. That material is expensive, and can release oxygen if its cell is overcharged. If the cobalt is replaced with iron phosphates, the cells will not burn or release oxygen under any charge. The price premium for early 2007 hybrids is about US $5000, some $3000 of which is for their NiMH battery packs. At early 2007 gasoline and electricity prices, that would break even after six to ten years of operation. The hybrid premium could fall to $2000 in five years, with $1200 or more of that being cost of lithium-ion batteries, providing a three-year payback.Voelcker, J. (January 2007) [http://spectrum.ieee.org/jan07/4848 "Lithium Batteries for Hybrid Cars"] "IEEE Spectrum"]
Other methods of energy storage
supercapacitors and flywheel energy storagedevices offering comparable storage capacity, higher charging rates, and lower volatility have the potential to overtake batteries as the prominent rechargeable storage for EVs. The FIAhas included their use in its sporting regulations of energy systems for Formula Onerace vehicles in 2007 and 2009, respectively. EEStorclaims to have developed a supercapacitorfor electricity storage. These units use barium titanate coated with aluminum oxide and glass to achieve a level of capacitance claimed to be much higher than what is currently available in the market. The claimed energy density is 1.0 MJ/kg (existing commercial supercapacitors typically have an energy density of around 0.01 MJ/kg, while lithium ion batteries have an energy density of around 0.54–0.72 MJ/kg). EEStor claims a less than 5 minute charge should give the supercapacitor sufficient energy to drive a car 400 km (250 mi). [ [http://media.cleantech.com/2644/zenn-gearing-up-for-eestor-powered-car Zenn gearing up for EEStor-powered car] ]
Solar taxiand Solar vehicle
Hobbyists, conversions, and racing
Hobbyists often build their own EVs by converting existing production cars to run solely on electricity. There is a
cottage industrysupporting the conversion and construction of BEVs by hobbyists. Universities such as the University of California, Irvineeven build their own custom electric or hybrid-electric cars from scratch.
Short-range battery electric vehicles can offer the hobbyist comfort, utility, and quickness, sacrificing only range. Short-range EVs may be built using high-performance lead–acid batteries, using about half the mass needed for a 100 to 130 km (60 to 80 mi) range. The result is a vehicle with about a 50 km (30 mi) range, which, when designed with appropriate weight distribution (40/60 front to rear), does not require
power steering, offers exceptional acceleration in the lower end of its operating range, and is freeway capable and legal. But their EVs are expensive due to the higher cost for these higher-performance batteries. By including a manual transmission, short-range EVs can obtain both better performance and greater efficiency than the single-speed EVs developed by major manufacturers. Unlike the converted golf carts used for neighborhood electric vehicles, short-range EVs may be operated on typical suburban throughways (60 to 70 km/h (40 to 45 mph) speed limits are typical) and can keep up with traffic typical on such roads and the short "slow-lane" on-and-off segments of freeways common in suburban areas.
Japanese Professor Hiroshi Shimizu from Faculty of Environmental Information of the
Keio Universitycreated the limousine of the future: the Eliica(Electric Lithium Ion Car) has eight wheels with electric 55 kilowatt hub motors (8WD) with an output of 470 kilowatts and zero emissions, a top speed of 370 kilometers per hour (230mph), and a maximum range of 320 kilometers provided by lithium-ion-batteries ( [http://www.eliica.com/ video at eliica.com] ). However, current models cost approximately $300,000 US, about one third of which is the cost of the batteries.
Alternative green vehicles
Other types of green vehicles include vehicles that move fully or partly on alternative energy sources rather than
fossil fuel. Another option is to use alternative fuel composition in conventional fossil fuel-based vehicles, making them go partly on renewable energy sources.
Other approaches include
personal rapid transit, a public transportation concept that offers automated on-demand non-stop transportation, on a network of specially-built guideways.
Electric motorcycles and scooters
Electric vehicle conversion
Compressed air car
List of emerging technologies
List of production battery electric vehicles
Neighborhood electric vehicle
Project Better Place
*, E. E. Keller, "Electrically Propelled Perambulator"
Hiram Stevens Maxim, "Motor vehicle"
*, H. S. Maxim, "Electric motor vehicle"
* [http://www.osgv.org/ Open Source Electric Car] by Society for Sustainable Mobility
* [http://www.eaaev.org/ US Electric Auto Association (EAA)] and [http://www.eaaev.org/eaaevcharging.html recharging points]
* [http://www.ElectricCarSociety.com/ Electric Car Society founded in 1982]
Electric Vehicle Comparison Websites
* [http://www.electriconwheels.com/ Electric On Wheels] Complete electric vehicle comparison rating website
* [http://www.autobloggreen.com/2008/09/29/chrysler-half-of-all-cars-electric-by-2020/ Chrysler: Half of cars sold by 2020 will be electric] September 2008
* [http://earth2tech.com/2008/08/28/toyota-cuts-sales-forecast-touts-ev/ Toyota to introduce small all electric city car in 2010] [http://www.businessweek.com/globalbiz/content/aug2008/gb20080828_357593.htm?chan=rss_topStories_ssi_5] August 2008
* [http://www.autoweek.com/apps/pbcs.dll/article?AID=/20061107/FREE/61106014/1024/STATIC GM does U-turn on electric car program, now says electric cars are the future]
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