Thursday, 1 August 2013

PASSAGE

Education

Read the following passage carefully and answer the questions given below it.

As the price of gasoline spiked to record highs in 2007 and 2008, interest in alternatives to fossil fuels, and electric transportation in particular, also spiked. It raised however, many questions about the true environmental impact of electric cars.

The electric car is being upheld as an ethical, green, nifty and cheap alternative to the carbon dioxide-emitting automobiles clogging city roads around the world today. Though electric cars are not a popular choice, the industry's future plans are riding high on the hope that on improving certain factors, (which are currently deficient) such ,as, effective marketing, a growing public awareness of the need for clean air and the increase in demand, the prices would eventually be driven down.

However, battery powered vehicles may still fail to completely replace liquid fuel-fed ones but with more electric and hybrid vehicles on the road, there is greater scope for makeover in the way environment is impacted by the automobiles. However, if the power to charge the battery-operated vehicle is to be sourced from grids using conventional coal-fired power plants, the electric car wouldn't really be all that green. These would actually cause an increase in demand on the power plant's energy production causing them to produce more power and thus more pollution, unless greener ways of energy production are used. But as of now the bulk of the electricity used to charge the batteries of electric vehicles is generated by fossil fuel burning power stations and only 12% by the clean methods. Also the amount of energy used by coal fired power stations to create the electricity to recharge electric vehicles makes them half as efficient as diesel cars. Recent studies indicate that carbon emissions may reduce only by an insignificant level even if there is a sudden Surge in demand for electric cars.

Other factors making the rechargeable cars less include the amount of electricity lost in the journey between the coal fired power stations which generate it and the point where it recharges the car, and the energy lost by the faulty first-generation batteries and motors. The researchers calculated that of the energy burned in a power station, only a quarter reaches an electric car after leakages and losses along the supply chain, giving the vehicle an energy efficiency score of 24%. These amounts to more than 75% energy loss much before the car is even put on ignition: A modern diesel engine, by contrast, achieves 45% efficiency. This suggests that if fossil fuels are to be burned, it is much more efficient to do it within the engine of a vehicle rather than at a power station' and then try to send it via the National Grid, where a lot of energy is wasted, and finally to store it in a battery which in itself might leak power.

Electric cars may still survive since the cars emissions would be far · less polluting than those that run on fossil fuels. 'With very minor emissions of sulphur caused when the batteries charge and discharge, when compared to current emissions standards, electric cars are zero emissions. The gasoline engine by comparison does not fare as well. Gasoline and diesel fuel burned in internal combustion engines for transportation-account for 54 percent of nitrities of oxygen, 89 percent of carbon monoxide and 28 percent of carbon dioxide pollution produced. Switching to electric vehicles drops those percentages to zero, and only slightly increases sulfur emissions. So even when the power plants burn dirty fuel, the amount of pollution is less than an oil burning car would create. And this picture is improving all the time, as clean energy sources are added to the grid.

The goal should be to make more electric cars with greater incentives for consumers and producers, as well as feeding grids with more power from renewable resources as per the objectives stated in the numerous plans on Climate Change. And till this goal is achieved, the debate whether controlling emission at a few power plants is more convenient than controlling emission at millions of tailpipes is, would continue.


1. PICTURE a) Situation b) Photograph c) Representation d) Art work e) Idea

A


2. FEEDING a) Eating b) Supplying c) Consuming d) Encouraging e) Nourishing

B


3. SURGE a) Alteration b) Modification c) Intensification d) Increase e) Evolution

D


4. SLIGHTLY a) Adequately b) Miserly c) Certainly d) Remotely e) Substantially

E


5. SWITCHING a) Prolonging b) Withdrawing c) Continuing d) Exchanging e) Alternating

B
































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