Hybrid cars are special because they benefit from more than one type of energy
About a week ago, India’s leading carmaker Maruti Suzuki announced its plans to introduce a new hybrid car. Other carmakers, notably Toyota and Honda have had success with hybrid cars abroad and have also tried introducing larger hybrid cars in India. What makes hybrid cars so special and noteworthy?
Today’s cars predominantly use fuels such as petrol and diesel in their engines. Our need to drive long distances in the shortest possible time leads to the consumption of a large amount of fuel; fuels that are non-renewable, lead to the increase in greenhouse gases and add to pollutants such as soot and other particulate matter in the air. For all these reasons, we would all prefer to use as little petrol and diesel as possible, or use an alternate energy source that is cheaper and cleaner. Using electricity as an energy source is one possible way. Electric cars such as India’s Reva have low emissions and are cheaper to use. But purely electric cars cannot run very long before needing to recharge, nor can they run at very high speeds. Hybrid cars are special because they marry both types of energies into one car allowing the user to reap the benefits of both – faster cars, longer distances because of fuel and diesel and cheaper, cleaner energy from electricity.
Hybrid cars have a gasoline engine and an electric motor allowing the car to draw energy from two types of sources. In most hybrids, the motor can also double up as a generator. When a car brakes and reduces speed, it essentially uses much of its energy. Hybrids reclaim some of this lost energy through the electric generator. Purely gasoline cars have large engines for the rare occasion when the car needs to achieve high speeds. But even while driving at average speeds, the large engine still uses a lot of fuel due to its sheer size and weight. In a hybrid, the engine is made intentionally smaller. When high speeds are required, the electric motor simply steps in to help out the smaller engine. The smaller engine allows a hybrid to use far less fuel during average speeds compared to an ordinary car. Because of the reduction in fuel need, the fuel tank is made smaller too. All of this leads to a significantly lighter car, making it far more fuel efficient. Besides, when the car has fully halted, the gasoline engine can be stopped leaving only the electric motor on.
If the hybrid car is clearly the superior car, why aren’t more of them on the road? If every car out there was a hybrid, they would all be plugging in to recharge from the national electric grid which is also driven on coal based fuels – perhaps making it no better than using petrol or diesel. That said, nations are fast adapting the grid to use renewable solar, tidal and wind energy. The electric battery made of nickel can have health impacts on the environment if not disposed of effectively. But today, the major impediment to its wide adoption is its price. Only developed in the last two decades, hybrid engine technology can be quite expensive, making it undesirable for all but the wealthiest and green-conscious of citizens. As with most technologies, the price can only fall with time, as we become better at building them and as more and more consumers buy them.
For now at least, the bets for a green future continue to be on hybrid cars.
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