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Electric Vehicles+context
An electric vehicle (EV) is a vehicle with one or more electric motors for propulsion. This is also referred to as an electric drive vehicle. The motion may be provided either by wheels or propellers driven by rotary motors, or in the case of tracked vehicles, by linear motors.
+resources and best practices
Electric Vehicles+background
History
Electric motive power started with a small railway operated by a miniature electric motor, built by Thomas Davenport 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.[1]
Between 1832 and 1839 (the exact year is uncertain), Robert Anderson of Scotland invented the first crude electric carriage, powered by non-rechargeable Primary cells.[2]
By the 20th century, electric cars and rail transport were commonplace, with commercial electric automobiles having the majority of the market. Over time their general-purpose commercial use reduced to specialist roles, as platform trucks, forklift trucks, tow tractors and urban delivery vehicles, such as the iconic British milk float; for most of the 20th century, the UK was the world's largest user of electric road vehicles.[3]
Electrified 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 electrification of their rail network. One of the earliest rechargeable batteries - the Nickel-iron battery - was favored by Edison for use in electric cars.
Electric vehicles 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 out-sold gasoline-powered vehicles.
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 conspiracy, but were acquitted of conspiring to monopolize the provision of transportation services. Electric tram line technologies could be used to recharge BEVs and PHEVs on the highway while the user drives, providing virtually unrestricted driving range. The technology is old and well established (see : Conduit current collection, Nickel-iron battery). The infrastructure has not been built.
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, Nissan and Toyota also produced limited numbers of EVs for California drivers. In 2003, upon the expiration of EV1 leases, GM crushed them. The crushing has variously been attributed to 1) the auto industry's successful federal court challenge to California's zero-emissions vehicle mandate, 2) a federal regulation requiring GM to produce and maintain spare parts for the few thousands EV1s and 3) the success of the Oil and Auto industries' media campaign to reduce public acceptance of electric vehicles.
Electric Vehicles+definitions
Unlike an internal combustion engine (ICE) that is tuned to specifically operate with a particular fuel such as gasoline or diesel, an electric drive vehicle needs electricity, which comes from sources such as batteries or a generator. This flexibility allows the drive train of the vehicle to remain the same, while the fuel source can be changed.
The electricity used to propel the vehicle may be provided in many different ways, the energy can come from any source, fossil fuels, nuclear power, tidal power, solar, wind etc. and this energy can either be supplied to the vehicle continuously as it is used or stored in the vehicle in some way, such as batteries or fuel cells.
Electric vehicles can include electric cars, electric trains, electric airplanes, electric boats, and electric motorcycles and scooters even electric spacecraft.
Electric Vehicles+best practices
Google revs up smart charging for plug-ins
by Martin LaMonica for CNET.com June 18, 2009
an overview of google's plans to deal with how the grid reacts to more and more electric cars being charged through the common electrical grid throughout the US
Electric Vehicles+issues
Issues regarding electric vehicles:
Energy sources
Main article on wikipedia: Renewable electricity
Although electric vehicles have few direct emissions, all rely on energy created through electricity generation, emit pollution and generate waste, unless it is generated by renewable source power plants. Since electric vehicles use whatever electricity is delivered by their electrical utility/grid operator, electric vehicles can be made more efficient or less polluting by modify 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 efficiency and pollution standards take years to filter through a nation's fleet of vehicles. New efficiency and pollution standards rely on the purchase of new vehicles, often as a 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.
Electric vehicles will take advantage of whatever environmental gains happen when a renewable energy generation station comes online, a fossil fuel 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 inefficient sources, the reverse can happen. Even in such a situation, electrical vehicles are still more efficient 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), and switch at any time between the two.
Efficiency
Because of the different methods of charging possible, the emissions produced have been quantified in different ways. Plug-in EV and hybrids also have different consumption characteristics.[6]
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.[7] Electric motors can be shielded within a metallic Faraday's cage, but this reduces efficiency by adding weight to the vehicle, while it is not conclusive that all electromagnetic radiation can be contained.
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 efficiency of electric vehicles over the entire cycle. In the USA it has been estimated there is already nearly sufficient existing power plant and transmission infrastructure, assuming that most charging would occur overnight, using the most efficient off-peak base load sources.[8]
Issues with batteries
Main article: Electric vehicle battery
75 watt-hour/kilogram lithium ion polymer battery
prototypes. Newer Li-poly cells provide up to 130 Wh/kg and last through thousands of charging cycles.On an energy basis, the price of electricity to run an EV is a small fraction of the cost of liquid fuel needed to produce an equivalent amount of energy. Issues related to batteries, however, can add to the operating costs.
Traditionally, most EVs have used lead-acid batteries due to their mature technology, high availability, and low cost (exception: some early EVs, such as the Detroit Electric, used nickel-iron.) Like all batteries, these have an environmental impact through their construction, use, disposal or recycling. On the upside, vehicle battery recycling rates top 95% in the United States. Deep-cycle lead batteries are expensive and have a shorter life than the vehicle itself, typically needing replacement every 3 years.
Lead-acid batteries in EV applications end up being a significant (25%-50%) portion of the final vehicle mass. Like all batteries, they have significantly lower energy density than petroleum fuels—in this case, 30-40Wh/kg. While the difference isn't as extreme as it first appears due to the lighter drive-train in an EV, even the best batteries tend to lead to higher masses when applied to vehicles with a normal range. The efficiency (70-75%) and storage capacity of the current generation of common deep cycle lead acid batteries decreases with lower temperatures, and diverting power to run a heating coil reduces efficiency and range by up to 40%[citation needed]. Recent advances in battery efficiency, capacity, materials, safety, toxicity and durability are likely to allow these superior characteristics to be applied in car-sized EVs.
Charging and operation of batteries typically results in the emission of hydrogen, oxygen and sulfur, which are naturally occurring and normally harmless if properly vented. Early Citicar owners discovered that, if not vented properly, unpleasant sulfur smells would leak into the cabin immediately after charging.
Lead-acid batteries have been re-engineered by Firefly Energy, increasing longevity, slightly increasing energy density, and significantly increasing power density. Firefly is expected market lightweight vehicle batteries, either directly or through manufacturing partners in 2008.
Lead-acid batteries powered such early-modern EVs as the original versions of the EV1 and the RAV4EV.
Nickel-metal hydride batteries are now considered a relatively mature technology. While less efficient (60-70%) in charging and discharging than even lead-acid, they boast an energy density of 30-80Wh/kg, far higher than lead-acid. When used properly, nickel-metal hydride batteries can have exceptionally long lives, as has been demonstrated in their use in hybrid cars and surviving NiMH RAV4EVs that still operate well after 100,000 miles (160,000 km) and over a decade of service. Downsides include the poor efficiency, high self-discharge, very finicky charge cycles, and poor performance in cold weather. GM Ovonic produced the NiMH battery used in the second generation EV-1, and Cobasys makes a nearly identical battery (ten 1.2V 85Ah NiMH cells in series in contrast with eleven cells for Ovonic battery). This worked very well in the EV-1. Patent encumbrance has limited the use of these batteries in recent years.
The sodium or "zebra" battery uses a molten chloroaluminate (NaAlCl4) sodium as the electrolyte. This chemistry is also occasionally referred to as "hot salt". A relatively mature technology, the Zebra battery boasts an energy density of 120Wh/kg and reasonable series resistance. Since the battery must be heated for use, cold weather doesn't strongly affect its operation except for in increasing heating costs. They have been used in several EVs. Zebras can last for a few thousand charge cycles and are nontoxic. The downsides to the Zebra battery include poor power density (<300 W/kg) and the requirement of having to heat the electrolyte to ~270*C, which wastes some energy and presents difficulties in long-term storage of charge.
Zebra batteries have been used in the Modec vehicle commercial vehicle since it entered production in 2006.
Lithium-ion (and similar lithium polymer) batteries, widely known through 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 energy density[9] and good power density, and 80 to 90% charge/discharge efficiency. The downsides of traditional lithium-ion batteries include short cycle lifes (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. The maturity of this technology is moderate. The Tesla Roadster 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 energy density to provide extreme power density, 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[10], and LG Chem expecting their lithium-manganese spinel batteries to last up to 40 years.[11]
Much work is being done on lithium ion batteries in the lab[12]. Lithium vanadium oxide has already made its way into the Subaru prototype G4e, doubling energy density. Silicon nanowires[13][14][15], silicon nanoparticles[16], and tin nanoparticles[17][18] promise several times the energy density in the anode, while composite[19][20][21][22][23] and superlattice[24] cathodes also promise significant density improvements.
In 2009 Mitsubishi (i-MiEV) and Subaru (Stella) introduced electric vehicles offered for fleet then public sale.
Charging stations
Main article: Charging station
Electric vehicles typically charge from either outlets or dedicated charging stations, a process that typically takes hours. One proposed solution is "rapid charging", such as the Aerovironment PosiCharge line (up to 250kW) and the Norvik MinitCharge line (up to 300kW). Ecotality is a manufacturer of Charging Stations and has partnered with Nissan on several installations. Battery replacement is also proposed as an alternative, although no OEM's including Nissan/Renault have any production vehicle plans. Swapping requires standardization across platforms, models and manufacturers. Swapping also requires many times more battery packs to be in the system. In spite of these obvious engineering and economic obstacles, Project Better Place has reportedly gained commitments of several hundred million dollars to build several electric vehicle networks of charging and battery replacement stations. The leader in the establishing the charging infrastructure is Coulomb Technologies which has deployed hundreds of stations and only requires a 30 day lead time to install a station.
One type of battery "replacement" proposed is much simpler: while the latest generation of vanadium redox battery only has an energy density similar to lead-acid, the charge is stored solely in a vanadium-based electrolyte, which can be pumped out and replaced with charged fluid. The vanadium battery system is also a potential candidate for intermediate energy storage in quick charging stations because of its high power density and extremely good endurance in daily use. System cost however, is still prohibitive. As vanadium battery systems are estimated to range between $350–$600 per kWh, a battery that can service one hundred customers in a 24 hour period at 50 kWh per charge would cost $1.8-$3 million.
Other in-development technologies
Main article: Electric double-layer capacitor
Conventional electric double-layer capacitors are being worked to achieve the energy density of lithium ion batteries, offering almost unlimited lifespans and no environmental issues. High-K electric double-layer capacitors, such as EEStor's EESU, promise to best lithium ion energy density several times over if they can be produced. Lithium-sulphur batteries offer 250Wh/kg[25]. Sodium-ion batteries promise 400Wh/kg with only minimal expansion/contraction during charge/discharge and a very high surface area[26].
Mechanically rechargeable batteries
There is another way to "refuel" electrical vehicles. Instead of recharging them from electric socket, batteries could be mechanically replaced on special stations just in a couple of minutes.
The general rule here is the more energy density a battery has the more difficult it is to recharge electrically.
There is Vanadium and Titanium diboride batteries which have great energy density [27], but can't be recharged electrically. Instead, thermal methods of recharging could be used. If coal, nuclear or geothermal energy used as a source, overall efficiency could be much better than in electrically rechargeable batteries, but can be environmental externalities. Although renewable energy sources also could be used to recharge such type of batteries with high efficiency.
Disadvantages of electric vehicles
Many electric designs have limited range, due to the low energy density of batteries compared to the fuel of internal combustion engined vehicles. Electric vehicles also often have long recharge times compared to the relatively fast process of refueling a tank. This is further complicated by the current scarcity of public charging stations.
Contrary to widespread belief, according to Department of Energy research conducted at Pacific National Laboratory, 84% of existing vehicles could be switched over to plug-in hybrids without requiring any new grid infrastructure.[28] In terms of transportation, the net result would be a 27% reduction in carbon dioxide emissions, a slight reduction in nitrous oxide emissions, an increase in particulate matter emissions, the same sulfur dioxide emissions, and the near elimination of carbon monoxide and volatile organic compound emissions. The emissions would be displaced away from street level and have correspondingly less effect on human health.
Electric and hybrid cars are seen as environmentally-friendly. While they do have reduced carbon emissions, the energy they consume is usually produced by means which are harmful to the environment, such as coal, nuclear or hydroelectricity. Electric cars may lead consumers to believe that buying a car is an environmentally-sound choice, whereas the ideal choice would be to make a lifestyle change in favor of walking, biking or public transit. Governments may invest in research and development of electric vehicles instead of developing public transit and pedestrian-friendly communities.
Heating of electric vehicles
In cold climates considerable energy is needed to heat the interior of the vehicle, and to defrost the windows. With IC engines this heat can come for free from the waste heat from the engine cooling circuit. If this is done with battery power cars, this will require extra energy from the battery, although some could be harvested from the motor and battery itself. There is not as much waste heat available as from an ICE engine.
However when plugged into the grid electric vehicles can be preheated, or cooled, and need little or no energy from the battery pack, especially for short trips.
Newer designs are focused on using super-insulated cabins which can heat the car using the body heat of the passengers.
http://en.wikipedia.org/wiki/Electric_vehicle#Issues_regarding_electric_vehicles
Electric Vehicles+lessons learned
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 film 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.
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 now sell, five years later, at over their original forty-thousand-dollar price.
The production of the Citroën Berlingo Electrique stopped in September 2005.
Electric Vehicles+standards in field
http://www.inhabitat.com/2009/07/14/us-postal-service-buys-1600-fuel-efficient-vehicles/
