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ALTERNATIVE VEHICLES



At the present rate of production oil supplies will run out rather soon, and we will have to look for other sources of energy. What kind of vehicle will then dominate? Nowadays car makers discuss four promising types of cars: fuel cell cars, electric cars, hybrid cars, and solar electric cars.

The electric car has a long history. The first electrical cars were built at the end of 19th century, but they could not compete against the internal combustion engine. Success of the electric car depends on light weight battery, capable of being recharged quickly, and the availability of electric energy. Several companies already sell electrics. For example, Solar Electric Engineering of Santa Rosa, California, offers Solar Electric's Destiny 2000 which includes an array of solar cells which provides a tiny bit of power and extends battery life. With its lightweight fiberglass body, it can travel 40 to 60 miles on a charge and cruises at 60-70 mph.

There are many different electric cars around the world. They are used for local deliveries, post offices and the services. But will the electric car ever be­come a universal means of transport? Today there are several hundred million cars in the world not to mention millions of motorcycles. It is estimated that if these changed over to electricity, they would require six million kilowatt hours, and all the power stations in the world now generate only a little over a third of that. The hydrogen/air fuel cells look very hopeful. These do not have to be charged, they generate their own energy from a chemical reaction. They convert fuel energy to electrical energy with better than 80% efficiency. But at present the fuel cells prove too expensive. A hybrid system where electric batteries for city driving would be recharged in highway driving with gasoline fuel is an alternative to the totally electrical system.

The use of fuel cells promises a reduction in environmental pollution from car exhaust emissions and the end of our dependence on oil for fuel. A fuel cell produces an electric current and heat by converting hydrogen and oxygen into water. When many cells are combined into a stack, enough energy is produced to power a 50kW engine. The fuel cell has the highest efficiency in power generation, reaching over 60%, compared to a gasoline-powered car which has 20%. Pure hydrogen could be stored on-board the car, but this would use too much space. Alternatively, car makers could use reformer technology to convert gasoline or methanol into hydrogen, but this would reduce the efficiency of the cell.

There are many practical considerations for drivers. Fuel cell-powered cars are neither as fast nor as quiet as gasoline- or diesel-powered cars. At present there are very few hydrogen fuelling stations, so refueling could be a problem. Fuel cell cars are very expensive to develop and produce, which means they will also be expensive for the customer. Many drivers will not pay extra for ‘green’ car technology. Nevertheless, the race is on to produce the first fuel cell-powered family car with CO2 emissions of 90g/km.



4. Match these English phrases with their equivalents in Ukrainian:





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