текст Fuel Cells

текст Fuel Cells 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. The output of a single cell is 0.6-0.8V, but when many cells are combined into a stack, enough energy is produced to power a 50 kW engine.
The fuel cell has the highest efficiency in power generation, reaching over 60%, compared to a gasoline-powered car which has 20%.
The oxygen required comes from the air, but hydrogen is not so readily available. Pure hydrogen could be stored on-board the car, but this would use too much space. Alternatively, carmakers could use reformer technology to convert gasoline or methanol into hydrogen, but this would reduce the efficiency of the ceil.
For drivers there are many practical considerations. 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 refuelling could be a problem. Fuel cell cars have a shorter range, $0 drivers will have to refuel more often. If a tank of hydrogen is stored on board, there are problems of space and safety.
Fuel cell cars are very expensive todevelop and produce, which means they will also be expensive for the customer. Many drivers will not pay extra for ‘green’ car technology, especially if it is not as convenient as the current system. Nevertheless, the race is on to produce the first fuel cell-powered family car with COa emissions of 90 g/km (equivalent to gasoline consumption of 3.0 l/ioo km).