Coal production declined in the 1970s because of increasing use of subsidized petroleum fuels. However, in the late 1970s Suharto announced a new effort to increase domestic coal use, especially in cement and electric power plants. Total coal production rose steadily in the 1980s to reach 11 million tons in 1990. Most coal reserves were located in southern Sumatra and eastern and southern Kalimantan. Total measured reserves were 4.2 billion tons, with an additional 12.9 billion tons classified as inferred reserves and 15 billion tons of hypothetical reserves. A government mining company, P.T. Tambang Batubara Bukit, produced the majority of coal in 1991, but ten coal cooperation contracts signed between 1981 and 1987 with foreign investors were expected to produce a total of 20 to 25 million tons per year by 1994.

Data as of November 1992