Fossil fuel reserves calculation

Calculation of Fossil Fuel Reserves Depletion Times... 

We note in passing that the consumption of crude oil, natural gas, and coal is expected to increase at 2%-3% [14], and that the reserves typically are replaced at various rates as well. The simple calculation indicates that in about 50 years, the age of fossil fuels will begin to end due to the depletion of crude oil. The fossil fuel age will have to end when the coal reserves run out in about two centuries. This gives us at least 50 years and at most 200 years to make the transition to the sustainable age In the next 20-30 years, however, fossil fuels will play an important role, as projections of the U.S. Energy Information Administration in the 2010 Energy Outlook indicate [19]. 

Nonrenewable/abiotic resource depletion potential is calculated for fossil fuels, metals and minerals by dividing the quantity of resource used by the estimated total world reserves of that resource. 

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