As long as we depend on oil to fuel the engines of the world, it will continue to play a major role in our lives. But research is ongoing in many countries to find ways to harness new sources of energy.
One thing that is certain, however, is that the air pollution resulting from the combustion of fossil fuels such as petroleum and coal is of increasing concern to the inhabitants of planet Earth. Thus, the search for a nonpolluting replacement energy source is one of the most important challenges faced by humankind.