In 1989, the world reserves of brown coal were estimated at 6800 ~10” kwhr, of which 860 x 10” kwhr are proven reserves. By 1992, these proven reserves had increased by ca. 30 %.
With the huge coal deposits available, the world’s energy requirements could be met for a long time to come. According to studies at several institutes, this could be for several thousand years at the current rate of growth.