MINING: Coal Reserves Dip Well Below Estimates
Recent Gauteng Business News
Dr Chris Hartnady, research and technical director at earth sciences consultancy Umvoto Africa, researched and discussed these latest assessments in the Sep/Oct 2010 edition of the South African Journal of Science.
Coal production increased dramatically from about 69 Mt/yr (million tonnes per year) to 179 Mt/yr between 1975 and 1985, and by 1989 the cumulative production had reached 4 Gt. Despite doubling since to just over 8 Gt, the underlying pattern has been one of faltering growth. Analysis based on the methodology of eminent American geologist, M King Hubbert, says Hartnady, predicts a peak in production rate of around 284 Mt/yr in 2020, at which stage approximately half of the total resource will be exhausted.
Production is forecast to fall back to the present-day rate of about 250 Mt/yr by 2037 and by 2063, when the resource is 90% exhausted, the production rate will be about 125 Mt/yr – the level last seen in the early 1980s.
The Waterberg Coalfield (Ellisras Basin) may be a remaining large resource, but structural complexity, finely interbedded coal strata at great depths, low grades, high ash content and water scarcity are likely to inhibit its development.
The circumstances are reminiscent of those in Britain, he says, where coal reserves were grossly over-estimated by conventional techniques and remained a large multiple of future production until shortly before the effective collapse of the industry in the 1980s.
“Rather than reserves being an indicator of future production, it seems Hubbert’s method of analysing the trend of past production is a more reliable predictor of reserves. This experience in Britain should serve as a salutary warning to South African coal geologists,” said Dr Hartnady.
Emissions from energy supply and use (excluding transport emissions) account for more than 70% of SA’s total greenhouse gas emissions, so the predicted peak coal production in 2020 is good news for the environment. However, given South Africa’s heavy dependence on coal for power generation and electricity supply, peak coal in 2020 will create problems for the future economic growth situation.
Most of the industrial world’s social organisations, legal systems and financial structures have evolved during the 19th and 20th centuries in an atmosphere of continued exponential growth fuelled mainly by fossil carbon and hydrocarbon resources. The world, including Southern Africa, is now entering a stage where restraints on exponential growth, in the form of overcrowding, resource exhaustion and environmental degradation, have become obvious for all to see, but its exponential-growth culture is ill-adapted to deal with the problems of non-growth.
As Hubbert wrote in 1977, quotes Hartnady: “In the face of this impending cultural crisis, if a major catastrophic solution is to be avoided, it is imperative that the predicament the world has reached be understood. The knowledge essential to competent intellectual leadership in the impending difficult situation is preeminently geological – a knowledge of the earth’s history and evolution of its organisms, a knowledge of the earth’s mineral and energy resources.”
Business News Sector Tags: Mining|