Future of Mobility
Electric vehicle
Introduction:-
An electric vehicle (EV), also referred to as an electric drive vehicle, is a vehicle which uses one or more electric motors for propulsion. Depending on the type of vehicle, motion may be provided by wheels or propellers driven by rotary motors, or in the case of tracked vehicles, by linear motors. Electric vehicles can include electric cars, electric trains, electric trucks, electric lorries, electric airplanes, electric boats, electric motorcycles and scooters, and electric spacecraft.
An electric car is an alternative fuel automobile that uses electric motors and motor controllers for propulsion, in place of more common propulsion methods such as the internal combustion engine (ICE). Electricity can be used as a transportation fuel to power battery electric vehicles (EVs). EVs store electricity in an energy storage device, such as a battery. The electricity powers the vehicle's wheels via an electric motor. EVs have limited energy storage capacity, which must be replenished by plugging into an electrical source.
Electric vehicles are different from fossil fuel-powered vehicles in that they can receive their power from a wide range of sources, including fossil fuels, nuclear power, and renewable sources such as tidal power, solar power, and wind power or any combination of those. However it is generated, this energy is then transmitted to the vehicle through use of overhead lines, wireless energy transfer such as inductive charging, or a direct connection through an electrical cable. The electricity may then be stored onboard the vehicle using a battery, flywheel, supercapacitor, or fuel cell. Vehicles making use of engines working on the principle of combustion can usually only derive their energy from a single or a few sources, usually non-renewable fossil fuels. A key advantage of electric or hybrid electric vehicles is their ability to recover braking energy as electricity to be restored to the on-board battery (regenerative braking) or sent back to the grid (V2G). At the beginning of the 21st century, increased concern over the environmental impact of the petroleum-based transportation infrastructure, along with the spectre of peak oil, led to renewed interest in an electric transportation infrastructure. As such, vehicles which can potentially be powered by renewable energy sources, such as hybrid electric vehicles or pure electric vehicles, are becoming more popular.
Electric cars have the potential of significantly reducing city pollution by having zero tail pipe emissions. Vehicle greenhouse gas savings depend on how the electricity is generated. With the U.S. energy mix using an electric car would result in a 30% reduction in carbon dioxide emissions. Given the current energy mixes in other countries, it has been predicted that such emissions would decrease by 40% in the UK, 19% in China, and as little as 1% in Germany.
History:
Electric motive power started in 1827, when Hungarian priest Anyos Jedlik built the ?rst crude but commutator, and the year after he used it to power a tiny car. A few years later, in 1835, professor Sibrandus Stratingh of University of Groningen, the Netherlands, built a small scale electric car and a Robert Anderson of Scotland is reported to have made a crude electric carriage sometime between the years of 1832 and 1839. Around the same period, early experimental electrical cars were moving on rails, too. American blacksmith and inventor Thomas Davenport built a toy electric locomotive, powered by a primitive electric motor, in 1835. In 1838, a Scotsman named Robert Davidson built an electric locomotive that attained a speed of four miles per hour (6 km/h). In England a patent was granted in 1840 for the use of rails as conductors of electric current, and similar American patents were issued to Lilley and Colten in 1847. Between 1832 and 1839 (the exact year is uncertain), Robert Anderson of Scotland invented the ?rst crude electric carriage, powered by non-rechargeable primary cells. The ?rst mass-produced electric vehicles appeared in America in the early 1900s. In 1902, "Studebaker Automobile Company" entered the automotive business with electric vehicles, though it also entered the gasoline vehicles market in 1904. However, with the advent of cheap assembly line cars by Ford, electric cars fell to the wayside. Due to the limitations of storage batteries at that time, electric cars did not gain much popularity, however electric trains gained immense popularity due to their economies and fast speeds achievable. By the 20th century, electric rail transport became commonplace. Over time their general-purpose commercial use reduced to specialist roles, as platform trucks, forklift trucks, ambulances, tow tractors and urban delivery vehicles, such as the iconic British milk ?oat; for most of the 20th century, the UK was the world's largest user of electric road vehicles. Electri?ed trains were used for coal transport, as the motors did not use precious oxygen in the mines. Switzerland's lack of natural fossil resources forced the rapid electri?cation of their rail network. One of the earliest rechargeable batteries - the nickel-iron battery - was favored by Edison for use in electric cars. EVs were among the earliest automobiles, and before the preeminence of light, powerful internal combustion engines, electric automobiles held many vehicle land speed and distance records in the early 1900s. They were produced by Baker Electric, Columbia Electric, Detroit Electric, and others, and at one point in history outsold gasoline-powered vehicles. In fact, in 1900, 28 percent of the cars on the road in the USA were electric. EVs were so popular that even President Woodrow Wilson and his secret service agents toured Washington, DC, in their Milburn Electrics, which covered 60–70 mi (100– 110 km) per charge.
A number of developments contributed to decline of electric cars. Improved road infrastructure required a greater range than that offered by electric cars, and the discovery of large reserves of petroleum in Texas, Oklahoma, and California led to the wide availability of affordable gasoline/petrol, making internal combustion powered cars cheaper to operate over long distances. Also internal combustion powered cars became ever easier to operate thanks to the invention of the electric starter by Charles Kettering in 1912, which eliminated the need of a hand crank for starting a gasoline engine, and the noise emitted by ICE cars became more bearable thanks to the use of the mu?er, which Hiram Percy Maxim had invented in 1897. As roads were improved outside urban areas electric vehicle range could not compete with the ICE. Finally, the initiation of mass production of gasoline-powered vehicles by Henry Ford in 1913 reduced signi?cantly the cost of gasoline cars as compared to electric cars. In the 1930s, National City Lines, which was a partnership of General Motors, Firestone, and Standard Oil of California purchased many electric tram networks across the country to dismantle them and replace them with GM buses. The partnership was convicted of conspiring to monopolize the sale of equipment and supplies to their subsidiary companies, but were acquitted of conspiring to monopolize the provision of transportation services.
Experimentation:
In January 1990, General Motors' President introduced its EV concept two seater, the "Impact", at the Los Angeles Auto Show. That September, the California Air Resources Board mandated major automaker sales of EVs, in phases starting in 1998. From 1996 to 1998 GM produced 1117 EV1s, 800 of which were made available through three-year leases. Chrysler, Ford, GM, Honda, and Toyota also produced limited numbers of EVs for California drivers. In 2003, upon thean AMC Gremlin modi?ed to take electric power; it had a range of about 50 miles on one charge. expiration of GM's EV1 leases, GM discontinued them. The discontinuation has variously been attributed to the auto industry's successful federal court challenge to California's zero emissions vehicle mandate, a federal regulation requiring GM to produce and maintain spare parts for the few thousands EV1s and the success of the oil and auto industries' media campaign to reduce public acceptance of EVs. A movie made on the subject in 2005-2006 was titled Who Killed the Electric Car? and released theatrically by Sony Pictures Classics in 2006. The ?lm explores the roles of automobile manufacturers, oil industry, the U.S. government, batteries, hydrogen vehicles, and consumers, and each of their roles in limiting the deployment and adoption of this technology. General Motors EV1 electric car (1996-1998), story told in movie Who Killed the Electric Car? Ford released a number of their Ford Ecostar delivery vans into the market. Honda, Nissan and Toyota also repossessed and crushed most of their EVs, which, like the GM EV1s, had been available only by closed-end lease. After public protests, Toyota sold 200 of its RAV EVs to eager buyers; they later sold at over their original forty-thousand-dollar price. This lesson did not go unlearned; BMW of Canada sold off a number of Mini EVs when their Canadian testing ended. The production of the Citro?n Berlingo Electrique stopped in September 2005.
Reintroduction:
During the last few decades, environmental impact of the petroleum based transportation infrastructure, along with the fear of peak oil, has led to renewed interest in an electric transportation infrastructure. EVs differ from fossil fuel-powered vehicles in that the electricity they consume can be generated from a wide range of sources, including fossil fuels, nuclear power, and renewable sources such as tidal power, solar power, and wind power or any combination of those. The carbon footprint and other emissions of electric vehicles varies depending on the fuel and technology used for electricity generation. The electricity may then be stored on board the vehicle using a battery, ?ywheel, or supercapacitors. Vehicles making use of engines working on the principle of combustion can usually only derive their energy from a single or a few sources, usually non-renewable fossil fuels. A key advantage of hybrid or plug-in electric vehicles is regenerative braking, which recovers kinetic energy, typically lost during friction braking as heat, as electricity restored to the on-board battery.
As of March 2018, there are some 45 series production highway-capable all electric cars available in various countries. As of early December 2015, the Leaf, with 200,000 units sold worldwide, is the world's top-selling highway-capable all electric car in history, followed by the Tesla Model S with global deliveries of about 100,000 units. Leaf global sales
As of January 2018, the world's two best selling all electric cars in history are the Nissan Leaf (left), with 300,000 in global sales and the Tesla Model S (right), with over 200,000 in global sales. achieved the 300,000 unit milestone in January 2018. As of May 2015, more than 500,000 highway-capable all-electric passenger cars and light utility vehicles have been sold worldwide since 2008, out of total global sales of about 850,000 light-duty plug-in electric vehicles. As of May 2015, the United States had the largest ?eet of highway-capable plug-in electric vehicles in the world, with about 335,000 highway legal plug-in electric cars sold in the country since 2008, and representing about 40% of the global stock. California is the largest plug-in car regional market in the country, with almost 143,000 units sold between December 2010 and March 2015, representing over 46% of all plug-in cars sold in the U.S. Cumulative global sales of all-electric cars and vans passed the 1 million unit milestone in September 2016.
Electricity sources
There are many ways to generate electricity, of varying costs, e?ciency and ecological desirability.
Connection to generator plants
Direct connection to generation plants as is common among electric trains, A passenger train, taking power through a third rail with return through the traction rails An electric locomotive at Brig, Switzerland Electric bus in Santa Barbara, California trolley buses, and trolley trucks collects power from electric power strips buried under the road surface through electromagnetic induction.
Onboard generators and hybrid EVs
Generated on-board using a diesel engine: diesel-electric locomotive generated on-board using a fuel cell: fuel cell vehicle generated on-board using nuclear energy: nuclear submarines and aircraft carriers renewable sources such as solar power: solar vehicle It is also possible to have hybrid EVs that derive electricity from multiple sources. Such as: on-board rechargeable electricity storage system (RESS) and a direct continuous connection to land-based generation plants for purposes of on highway recharging with unrestricted highway range on-board rechargeable electricity storage system and a fueled propulsion power source (internal combustion engine): plug-in hybrid Another form of chemical to electrical conversion is fuel cells, projected for future use. For especially large EVs, such as submarines, the chemical energy of the diesel-electric can be replaced by a nuclear reactor. The nuclear reactor usually provides heat, which drives a steam turbine, which drives a generator, which is then fed to the propulsion. See Nuclear Power A few experimental vehicles, such as some cars and a handful of aircraft use solar panels for electricity.
Onboard storage
These systems are powered from an external generator plant (nearly always when stationary), and then disconnected before motion occurs, and the electricity is stored in the vehicle until needed. On-board rechargeable electricity storage system (RESS), called Full Electric Vehicles (FEV). Power storage methods include: chemical energy stored on the vehicle in on-board batteries: Battery electric vehicle (BEV) kinetic energy storage: ?ywheels static energy stored on the vehicle in on-board electric double-layer capacitors Batteries, electric double-layer capacitors and ?ywheel energy storage are forms of rechargeable on-board electrical storage. By avoiding an intermediate mechanical step, the energy conversion e?ciency can be improved over the hybrids already discussed, by avoiding unnecessary energy conversions. Furthermore, electrochemical batteries conversions are easy to reverse, allowing electrical energy to be stored in chemical form.
Lithium-ion battery
Lithium-ion (and similar lithium polymer) batteries, widely known via their use in laptops and consumer electronics, dominate the most recent group of EVs in development. The traditional lithium-ion chemistry involves a lithium cobalt oxide cathode and a graphite anode. This yields cells with an impressive 200+ Wh/kg specific energy and good specific power, and 80 to 90% charge/discharge efficiency. The downsides of traditional lithium-ion batteries include short cycle lives (hundreds to a few thousand charge cycles) and significant degradation with age. The cathode is also somewhat toxic. Also, traditional lithium-ion batteries can pose a fire safety risk if punctured or charged improperly. These laptop cells don't accept or supply charge when cold, and so heaters can be necessary in some climates to warm them. The maturity of this technology is moderate. The Tesla Roadster (2008) uses "blades" of traditional lithium-ion "laptop battery" cells that can be replaced individually as needed.
Most other EVs are utilizing new variations on lithium-ion chemistry that sacrifice specific energy and specific power to provide fire resistance, environmental friendliness, very rapid charges (as low as a few minutes), and very long lifespans. These variants (phosphates, titanates, spinels, etc.) have been shown to have a much longer lifetime, with A123 expecting their lithium iron phosphate batteries to last for at least 10+ years and 7000+ charge cycles, and LG Chem expecting their lithium-manganese spinel batteries to last up to 40 years.
Much work is being done on lithium ion batteries in the lab. Lithium vanadium oxide has already made its way into the Subaru prototype G4e, doubling energy density Silicon nanowires, silicon nanoparticles, and tin nanoparticles promise several times the energy density in the anode, while composite and superlattice cathodes also promise significant density improvements.
Electric motor
The power of a vehicle's electric motor, as in other vehicles, is measured in kilowatts (kW). 100 kW is roughly equal to 134 horsepower, but electric motors can deliver their maximum torque over a wide RPM range. This means that the performance of a vehicle with a 100 kW electric motor exceeds that of a vehicle with a 100 kW internal combustion engine, which can only deliver its maximum torque within a limited range of engine speed. Energy is lost during the process of converting the electrical energy to mechanical energy. Approximately 90% of the energy from the battery is converted to mechanical energy, the losses being in the motor and drivetrain. Usually, direct current (DC) electricity is fed into a DC/AC inverter where it is converted to alternating current (AC) electricity and this AC electricity is connected to a 3phase AC motor. For electric trains, forklift trucks, and some electric cars, DC motors are often used. In some cases, universal motors are used, and then AC or DC may be employed. In recent production vehicles, various motor types have been implemented, for instance: Induction motors within Tesla Motor vehicles and permanent magnet machines in the Nissan Leaf and Chevrolet Bolt. It is generally possible to equip any kind of vehicle with an electric powertrain.
Plug-in electric vehicle
A plug-in electric vehicle (PEV) is any motor vehicle that can be recharged from any external source of electricity, such as wall sockets, and the electricity stored in the rechargeable battery packs drives or contributes to drive the wheels. PEV is a subcategory of electric vehicles that includes all-electric or battery electric The Chevrolet Volt is the world's top selling plug-in hybrid of all time. Global Volt/Ampera family sales passed the 100,000 unit milestone in October 2015. vehicles (BEVs), plug-in hybrid vehicles, (PHEVs), and electric vehicle conversions of hybrid electric vehicles and conventional internal combustion engine vehicles.
Cumulative global sales of highway capable light-duty pure electric vehicles passed one million units in total, globally, in September 2016. Cumulative global sales of plug-in cars and utility vans totalled over 2 million by the end of 2016, of which 38% were sold in 2016, and the 3 million milestone was achieved in November 2017.
As of January 2018, the world's top selling plug-in electric cars is the Nissan Leaf, with global sales of more than 300,000 units.[19] As of June 2016, it was followed by the all-electric Tesla Model S with about 129,400 units sold worldwide, the Chevrolet Volt plug-in hybrid, which together with its sibling the Opel/Vauxhall Ampera has combined global sales of about 117,300 units, the Mitsubishi Outlander P-HEV with about 107,400 units, and the Prius Plug-in Hybrid with over 75,400 units.
A hybrid electric vehicle combines a conventional (usually fossil fuel-powered) powertrain with some form of electric propulsion. As of April 2016, over 11 million hybrid electric vehicles have been sold worldwide since their inception in 1997. Japan is the market leader with more than 5 million hybrids sold, followed by the United States with cumulative sales of over 4 million units since 1999, and Europe with about 1.5 million hybrids delivered since 2000. Japan has the world's highest hybrid market penetration. By 2013 the hybrid market share accounted for more than 30% of new standard passenger car sold, and about 20% new passenger vehicle sales including kei cars. Norway ranks second with a hybrid market share of 6.9% of new car sales in 2014, followed by the Netherlands with 3.7% Global hybrid sales are by Toyota Motor Company with more than 9 million Lexus and Toyota hybrids sold as of April 2016, followed by Honda Motor Co., Ltd. with cumulative global sales of more than 1.35 million hybrids as of June 2014,Ford Motor Corporation with over 424,000 hybrids sold in the United States through June 2015, and the Hyundai Group with cumulative global sales of 200,000 hybrids as of March 2014, including both Hyundai Motor Company and Kia Motors hybrid models. As of April 2016, worldwide hybrid sales are led by the Toyota Prius liftback, with cumulative sales of over 3.7 million units. The Prius nameplate has sold more than 5.7 million hybrids up to April 2016.
On- and off-road EVs
EVs are on the road in many functions, including electric cars, electric trolleybuses, electric buses, battery electric buses, electric trucks, electric bicycles, electric motorcycles and scooters, personal transporters, neighborhood electric vehicles, golf carts, milk ?oats, and forklifts. Off-road vehicles include electri?ed all-terrain vehicles and tractors.
Railborne EVs
The ?xed nature of a rail line makes it relatively easy to power EVs through permanent overhead lines or electri?ed third rails, eliminating the need for heavy onboard batteries. Electric locomotives, electric trams/streetcars/trolleys, electric light rail systems, and electric rapid transit are all in common use today, especially in Europe and Asia. A streetcar (or Tram) drawing current from a single overhead wire through a pantograph. Since electric trains do not need to carry a heavy internal combustion engine or large batteries, they can have very good power to-weight ratios. This allows high speed trains such as France's double-deck TGVs to operate at speeds of 320 km/h (200 mph) or higher, and electric locomotives to have a much higher power output than diesel locomotives. In addition, they have higher short-term surge power for fast acceleration, and using regenerative brakes can put braking power back into the electrical grid rather than wasting it. Maglev trains are also nearly always EVs.
Energy and motors
Most large electric transport systems are powered by stationary sources of electricity that are directly connected to the vehicles through wires. Electric traction allows the use of regenerative braking, in which the motors are used as brakes and become generators that transform the motion of, usually, a train into electrical power that is then fed back into the lines. This system is particularly advantageous in mountainous operations, as descending vehicles can produce a large portion of the power required for those ascending. This regenerative system is only viable if the system is large enough to utilise the power generated by descending vehicles. In the systems above, motion is provided by a rotary electric motor. However, it is possible to "unroll" the motor to drive directly against a special matched track. These linear motors are used in maglev trains which ?oat above the rails supported by magnetic levitation. This allows for almost no rolling resistance of the vehicle and no mechanical wear and tear of the train or track. In addition to the high-performance control systems needed, switching and curving of the tracks becomes di?cult with linear motors, which to date has restricted their operations to high-speed point to point services.
Properties
Components
The type of battery, the type of traction motor and the motor controller design vary according to the size, power and proposed application, which can be as small as a motorized shopping cart or wheelchair, through pedelecs, electric motorcycles and scooters, neighborhood electric vehicles, industrial fork-lift trucks and including many hybrid vehicles.
Energy sources
Although EVs have few direct emissions, all rely on energy created through electricity generation, and will usually emit pollution and generate waste, unless it is generated by renewable source power plants. Since EVs use whatever electricity is delivered by their electrical utility/grid operator, EVs can be made more or less e?cient, polluting and expensive to run, by modifying the electrical generating stations. This would be done by an electrical utility under a government energy policy, in a timescale negotiated between utilities and government. Fossil fuel vehicle e?ciency and pollution standards take years to ?lter through a nation's ?eet of vehicles. New e?ciency and pollution standards rely on the purchase of new vehicles, often as the current vehicles already on the road reach their end-of-life. Only a few nations set a retirement age for old vehicles, such as Japan or Singapore, forcing periodic upgrading of all vehicles already on the road. EVs will take advantage of whatever environmental gains happen when a renewable energy generation station comes online, a fossil-fuel power station is decommissioned or upgraded. Conversely, if government policy or economic conditions shifts generators back to use more polluting fossil fuels and internal combustion engine vehicles (ICEVs), or more ine?cient sources, the reverse can happen. Even in such a situation, electrical vehicles are still more e?cient than a comparable amount of fossil fuel vehicles. In areas with a deregulated electrical energy market, an electrical vehicle owner can choose whether to run his electrical vehicle off conventional electrical energy sources, or strictly from renewable electrical energy sources (presumably at an additional cost), pushing other consumers onto conventional sources, and switch at any time between the two.
Issues with batteries
E?ciency
Lithium ion polymer battery prototypes. Newer Li-poly cells provide up to 130 Wh/kg and last through thousands of charging cycles. Because of the different methods of charging possible, the emissions produced have been quanti?ed in different ways. Plug-in all-electric and hybrid vehicles also have different consumption characteristics.
Electromagnetic radiation
Electromagnetic radiation from high performance electrical motors has been claimed to be associated with some human ailments, but such claims are largely unsubstantiated except for extremely high exposures. Electric motors can be shielded within a metallic Faraday cage, but this reduces e?ciency by adding weight to the vehicle, while it is not conclusive that all electromagnetic radiation can be contained.
Charging
Grid capacity
If a large proportion of private vehicles were to convert to grid electricity it would increase the demand for generation and transmission, and consequent emissions. However, overall energy consumption and emissions would diminish because of the higher e?ciency of EVs over the entire cycle. In the USA it has been estimated there is already nearly su?cient existing power plant and transmission infrastructure, assuming that most charging would occur overnight, using the most e?cient off-peak base load sources. In the UK however, things are different. While National Grid's high-voltage electricity transmission system can currently manage the demand of 1 million electric cars, Steve Holliday (CEO National Grid PLC) said, “penetration up and above that becomes a real issue. Local distribution networks in cities like London may struggle to balance their grids if drivers choose to all plug in their cars at the same time."
Charging stations
EVs typically charge from conventional power outlets or dedicated charging stations, a process that typically takes hours, but can be done overnight and often gives a charge that is su?cient for normal everyday usage. However, with the widespread implementation of electric vehicle A battery electric bus charging station in Geneva, Swiss networks within large cities in the UK and Europe, EV users can plug in their cars whilst at work and leave them to charge throughout the day, extending the possible range of commutes and eliminating range anxiety. A recharging system that avoids the need for a cable is Curb Connect, patented in 2012 by Dr Gordon Dower. In this system, electrical contacts are ?tted into curbs, such as angle parking spaces on city streets. When a suitably authorized vehicle is parked so that its front end overhangs the curb, the curb contacts become energized and charging occurs. Another proposed solution for daily recharging is a standardized inductive charging system such as Evatran's Plugless Power. Bene?ts are the convenience of parking over the charge station and minimized cabling and connection infrastructure. Qualcomm is trialling such a system in London in early 2012.
Safety
The United Nations in Geneva (UNECE) has adopted the ?rst international regulation (Regulation 100) on safety of both fully electric and hybrid electric cars, with the intent of ensuring that cars with a high voltage electric power train, such as hybrid and fully EVs, are as safe as combustion-powered cars. The EU and Japan have already indicated that they intend to incorporate the new UNECE Regulation in their respective rules on technical standards for vehicles There is a growing concern about the safety of EVs, given the demonstrated tendency of the Lithium-ion battery, most promising for EV use because of its high energy density, to overheat, possibly leading to ?re or explosion, especially when damaged in a crash. The U.S. National Highway Tra?c Safety Administration opened a defect investigation of the Chevy Volt on November 25, 2011 amid concerns over the risk of battery ?res in a crash. At that time, automotive consulting ?rm CNW Marketing Research reported a decline in consumer interest in the Volt, citing the ?res as having made an impact on consumer perception.[99] Consumer response impelled GM to make safety enhancements to the battery system in December, and the NHTSA closed its investigation on January 20, 2012, ?nding the matter satisfactorily resolved with "no discernible defect trend" remaining. The agency also announced it has developed interim guidance to increase awareness and identify appropriate safety measures regarding electric vehicles for the emergency response community, law enforcement o?cers, tow truck operators, storage facilities and consumers.
Advantages and disadvantages of EVs
Environmental
EVs release no tail pipe air pollutants at the place where they are operated. They also typically generate less noise pollution than an internal combustion engine vehicle, whether at rest or in motion. The energy that electric and hybrid cars consume is usually generated by means that have environmental impacts. Nevertheless, adaptation of EVs would have a signi?cant net environmental bene?t, except in a few countries that continue to rely on older coal ?red power plants for the bulk of their electricity generation throughout the life of the car. There are special kind of electric vehicles named SAFA TEMPO in Nepal that help lower the pollution created by vehicles. These vehicles are powered by electricity usually charged batteries - rather than oil or gas and currently heavily promoted by the government to facilitate environmental and vehicle management issues. Electric motors don't require oxygen, unlike internal combustion engines; this is useful for submarines and for space rovers. A study by Cambridge Econometrics shows the potential air pollution bene?ts of EVs. According to one of the scenarios in the study, Europe would be on track to reduce CO2 emissions from cars by 88% by 2050. The associated technology improvements would cut toxic nitrogen oxides (NOx) from cars from around 1.3 million tonnes per year to around 70,000 tonnes per year.
Energy e?ciency
EV 'tank-to-wheels' e?ciency is about a factor of 3 higher than internal combustion engine vehicles. Energy is not consumed while the vehicle is stationary, unlike internal combustion engines which consume fuel while idling. However, looking at the well-to-wheel e?ciency of EVs, their total emissions, while still lower, are closer to an e?cient gasoline or diesel in most countries where electricity generation relies on fossil fuel. Well-to-wheel e?ciency of an EV has less to do with the vehicle itself and more to do with the method of electricity production. A particular EV would instantly become twice as e?cient if electricity production were switched from fossil fuel to a wind or tidal primary source of energy. Thus, when "well-to-wheels" is cited, one should keep in mind that the discussion is no longer about the vehicle, but rather about the entire energy supply infrastructure - in the case of fossil fuels this should also include energy spent on exploration, mining, re?ning, and distribution. The lifecycle analysis of EVs shows that even when powered by the most carbon intensive electricity in Europe, they emit less greenhouse gases than a conventional diesel vehicle.
Cost of recharge
The cost of operating an EV varies wildly depending on location. In some parts of the world, an EV costs less to drive than a comparable gas-powered vehicle, as long as the higher initial purchase-price is not factored in . In the US, in states which have a tiered electricity rate schedule, "fuel" for EVs today costs owners signi?cantly more than fuel for a comparable gas-powered vehicle. A 2011 study done by Purdue University found that in California most users already reach the third pricing tier for electricity each month, and adding an EV could push them into the fourth or ?fth (highest, most expensive) tier, meaning that they will be paying in excess of $.45 cents per kWh for electricity to recharge their vehicle. At this price, which is higher than the average electricity price in the US, it is dramatically more expensive to drive a pure-EV than it is to drive a traditional pure-gas powered vehicle. "The objective of a tiered pricing system is to discourage consumption. It's meant to get you to think about turning off your lights and conserving electricity. In California, the unintended consequence is that plug-in hybrid cars won't be economical under this system," said Tyner (the author), whose ?ndings were published in the online version of the journal Energy Policy.
Stabilization of the grid
Since EVs can be plugged into the electric grid when not in use, there is a potential for battery powered vehicles to even cut the demand for electricity by feeding electricity into the grid from their batteries during peak use periods (such as mid afternoon air conditioning use) while doing most of their charging at night, when there is unused generating capacity. This vehicle-to-grid (V2G) connection has the potential to reduce the need for new power plants, as long as vehicle owners do not mind reducing the life of their batteries, by being drained by the power company during peak demand. Furthermore, our current electricity infrastructure may need to cope with increasing shares of variable-output power sources such as wind and solar PV. This variability could be addressed by adjusting the speed at which EV batteries are charged, or possibly even discharged. Some concepts see battery exchanges and battery charging stations, much like gas/petrol stations today. Clearly these will require enormous storage and charging potentials, which could be manipulated to vary the rate of charging, and to output power during shortage periods, much as diesel generators are used for short periods to stabilize some national grids.
Range
Electric vehicles may have shorter range compared to Internal Combusion Engines, however, the price per mile of electric vehicles is falling. Most owners opt to charge their vehicles primarily at their houses while not in use due to their typically slower charging times, and added convenience.
Heating of EV
In cold climates, considerable energy is needed to heat the interior of a vehicle and to defrost the windows. With internal combustion engines, this heat already exists as waste combustion heat diverted from the engine cooling circuit. This process offsets the greenhouse gases' external costs. If this is done with battery EVs, the interior heating requires extra energy from the vehicles' batteries. Although some heat could be harvested from the motor or motors and battery, their greater e?ciency means there is not as much waste heat available as from a combustion engine. However, for vehicles which are connected to the grid, battery EVs can be preheated, or cooled, with little or no need for battery energy, especially for short trips. Newer designs are focused on using super-insulated cabins which can heat the vehicle using the body heat of the passengers. This is not enough, however, in colder climates as a driver delivers only about 100 W of heating power. A heat pump system, capable of cooling the cabin during summer and heating it during winter, seems to be the most practical and promising way of solving the thermal management of the EV. Ricardo Arboix introduced (2008) a new concept based on the principle of combining the thermalmanagement of the EV-battery with the thermal-management of the cabin using a heat pump system. This is done by adding a third heat-exchanger, thermally connected with the battery-core, to the traditional heat pump/air conditioning system used in previous EV-models like the GM EV1 and Toyota RAV4 EV. The concept has proven to bring several bene?ts, such as prolonging the life-span of the battery as well as improving the performance and overall energy-e?ciency of the EV.
Future
Ferdinand Duden hoeffer, head of the Centre of Automotive Research at the Gelsenkirchen University of Applied Rimac Concept One, electric supercar, since 2013. 0 to 100 km/h in 2.8 seconds, with a total output of 800 kW (1,073 hp) Tesla Model S, since 2012. 0 to 100 km/h in 2.5 seconds, recharging in 30 minutes to 80 percent, range 600 km. Sciences in Germany, said that "by 2025, all passenger cars sold in Europe will be electric or hybrid electric".
Improved batteries
First, advances in lithium ion batteries, in large part driven by the consumer electronics industry, allow full-sized, highway-capable EVs to be propelled as far on a single charge as conventional cars go on a single tank of gasoline. Lithium batteries have been made safe, can be recharged in minutes instead of hours (see recharging time), and now last longer than the typical vehicle (see lifespan). The production cost of these lighter, higher capacity lithium batteries is gradually decreasing as the technology matures and production volumes increase. Toyota Motors Corporation is trying to replace the current lithium ion battery with solid-state battery technology by 2020. The solid-state battery replaces the liquid electrolyte with a solid electrolyte. Rechargeable lithium-air batteries potentially offer increased range over other types and are a current topic of research.
Conclusion
Day by day, uses of petroleum product is increasing in a rapid speed. In order to overcome these problem of fuel crisis in coming future, invention of an electric vehicles play an important role solving the fuel crisis. Many different type of electric cars are being invented and expected that it will be much helpful in future. Electric cars are important. Initial cost for buying these cars might be high but it will be most reliable here after.