About 1.2 trillion barrels is the amount of oil in the world today. The amount looks too huge but humans consume a huge amount. Besides, the supply of oil is decreasing. The demand outstrips the supply. Some believe that 1.2 trillion barrels would run out in 44 years if the present usage reports were taken into account.
There are contradictions as to when the oil reserves will run out. Some say that the world will enjoy oil for another 25 years while others contradict that oil will last for more than 40 years. There is definitely no conclusion as to when the world will run out of oil but the end is surely somewhere close. India and China, the two most developing countries in the world, have dramatically increased their oil usage in the past few years.
Coal, on the other hand, is said to have abundant reserves. Some people believe that coal reserves will not run out for another 250 to 350 years. This optimism can go haywire, as there is no certainty of other fossil fuels that may run out before time increasing the dependency of the entire world on the coal fuels. China has drastically increased its usage of coal with 2.3 billion tones every year.
One of the biggest troubles with coal is that it gives out carbon dioxide and toxic chemical gases when burnt. This cause air pollution and harms the environment through global warming. It is believed that coal will be an important source of fuel in the future and will not harm the environment once Carbon Capture and Storage technologies are developed and made to use.
The perishability of fossil fuels in the future is likely to result in a conflict between the nations of the world who attempt to secure themselves through the coal and oil reserves. The West, in particular, is crazy about adding to its oil reserves.
It would be MUCH convient if you could tell us what percent of the space on earth coal takes up.