According to a report published in Nature, although coal is plentiful, cheap coal may run out within a few decades. The article points out that the current large investments in carbon capture and storage are based on the assumption that coal will remain cheap for many decades but this may not be the case.

It is impossible to get an accurate, up-to-date picture of the world’s economically recoverable coal reserves. The United States, for example, has not updated its reserve estimates since 1974. However, there are reasons to think that the price of coal is likely to rise.

Some coal producing countries, including Germany and South Africa, have reduced their estimates of their economically recoverable coal supplies.

China, although it has the world’s largest deposits of coal, is unable to mine it quickly enough to meet demand and is forced to import coal from Australia and the United States – putting upward pressure on prices. India could face a similar situation in coming decades.

The article says that nations need to plan for the price of coal increasing and, like oil, becoming increasingly volatile as it does so.