Реферат: Electric Cars Essay Research Paper Potential Environmental
Electric Cars Essay, Research Paper
Potential Environmental and Social impact of ELECTRIC CARS
A wise person once said that: The only thing that we know about the future is its uncertainty. This uncertainty opens the world of opportunity to us, allowing progress to pave the road to tomorrow. Over the past fifty years, the automobile has become our primary way of transportation and not only for leisure, but a necessity for most people. With the convenience and the increasing number of cars each year, however, come serious consequences with long lasting effects.
For the last hundred years, ever since the first automobile was developed, most vehicles have been gasoline powered. An internal combustion engine, which utilizes chemical bond energy in petroleum, has been practically the only means of powering the vehicle. This type of engine has evolved a long way since its invention by a Dutch physicist Christian Huygens, in about 1680. Efficiency, noise and pollution levels have been drastically improved in its life cycle especially in the last 30 years, however the fundamental problem of reliance on petroleum products and simple chemical reaction of oxidation is still and always will be apparent. These shortcomings didn t cripple the development of automotive industry in the past, but today, when people are becoming more and more aware of problems associated with mass use of gasoline powered vehicles, there is clearly a need for an alternative source of power the electric power.
Despite stringent standards to improve tailpipe emissions, the number of vehicles and miles traveled are increasing every year. Scientists predict that our reliance on the automobile could increase pollution levels 40 percent by the year 2010. In California, 75 percent of our petroleum is used by the transportation sector; that represents one-half of all energy used in the state. In addition, greenhouse gases, such as carbon dioxide, are expected to increase approximately 33 percent by the year 2010. For the most part, in California, the internal combustion engine vehicles are the ones that account for about 90 percent of the carbon monoxide a highly poisonous gas that can reduce blood s ability to carry oxygen, 77 percent of nitrous oxides, poisonous gases that damage lung tissue, and 55 percent of reactive organic gases, some of which are carcinogenic and others irritating to mucous membranes. Continual exposure to these pollutants can cause a variety of symptoms and aggravate already existing medical conditions. While the whole population is exposed, children and the elderly, with much weaker immune systems, are more susceptible to the risks.
Public transit has been utilizing electric power for tens of years and has switched to electricity in favor of gasoline or steam powered engines. One particular example is London Underground train system, which was originally powered by steam engines and began using electricity out of the same concerns that general public now has for gasoline engine.
The public has been slow to respond to the overwhelming evidence for the need of alternative fuel sources and vehicles. At the turn of the new century, alternative fuel vehicles represent less then one percent of all vehicles on the road. However, the growing severity of air pollution, combined with the need to reduce America s dependence on imported oil, is causing us to reevaluate our current choices of transportation fuels.
An electric vehicle is a motor vehicle, such as an automobile, truck, or bus, that uses a rechargeable battery for fuel, replacing gasoline, diesel or other types of combustible fuels, thus producing no tailpipe or evaporative emissions. These vehicles have the unique advantage of using electricity generated from a variety of fuels and renewable resources: hydroelectric, solar, wind, and geothermal just to name a few. Refueling an electric vehicle consists of plugging in the vehicle’s charge plug into an outlet that is specifically designed for charging an electric vehicle. This brings up a concern that charging thousands of electric vehicles from aging coal plants, for example, will increase greenhouse gases such as CO2 significantly. However, research has shown that although CO2 will be produced, it will be much less then is produced now by internal combustion engines.
Currently the significant problems with electrical vehicles compared to ICE vehicles are their relatively short drive range per charge and their high cost. These are determined by very large, expensive, heavy and short-lived battery packs. Lead acid batteries are cheaper than alternative technologies but have low energy density. Some advanced batteries such as NiMH and NiCD, do have higher energy density than the lead acid battery, however, they are extremely expensive. Automakers are paying exorbitant sums for the advanced batteries they use in the current generation of electric vehicles, over US $30,000 per unit. This situation makes it very difficult for electric cars to be widely accepted and used.
The use of small, electric vehicles, as an alternative to the gasoline powered automobile, promises a way out of the existing crisis of polluted and congested cities. However, major problems confront these vehicles. Many critics perceive them to be dangerous, impractical and costly. They are justified in their concerns, but have based their conclusions on only a few pre-production vehicles and a physical environment, which is hostile to the needs of these vehicles and their drivers