Coal Futures: Will this energy standby truly last for centuries-or just decades

With the price of gasoline so volatile of late, it is not hard to accept the argument that the world may be entering the period of “peak oil,” a time in which the extraction of oil from the ground becomes limited by geological constraints on the amount globally available. Resource analysts differ in their assessments. Some believe the peak in oil production from conventional sources (which is to say, easily exploited ones) has already arrived. Others project that this key turning point may not come for another decade or more.

But one thing is for sure: The notion of peak oil has been on lots of people’s minds. Books and Web sites are full of the topic. Now a new study from a European organization called the Energy Watch Group proposes another daunting prospect: that the world might soon have to grapple with a peak in the production of coal, too.


This conclusion flies in the face of accepted wisdom on the topic, which is typically based on a comparison of the amount of coal left to be mined (reserves) with the amount used every year (production). The ratio of reserves to production provides a crude measure of how many years are left before the resource runs out, assuming that reserves don’t expand and that consumption stays constant. According to the Energy Information Administration, which provides official U.S. government energy statistics, the ratio of world reserves (tons of coal) to production (tons used per year) in 2002 was more than 200. That is to say, we might expect coal to last another 200 years. Considering the United States in isolation yields an even more optimistic number: 240 years.

One problem with such simpleminded assessments is that they ignore the way natural resources are actually depleted. Production does not continue at some constant rate for centuries and then suddenly stop. Rather, it tends to ramp upward to some peak rate, then decline. A reasonable expectation is that the production curve is symmetrical, with the peak taking place when about half of the total resource is used.

American Scientist