Peak coal: sooner than you think

Coal provides over a quarter of the world’s primary energy needs and generates 40 per cent of the world’s electricity. Two thirds of global steel production depends on coal.

Global consumption of coal is growing faster than that of oil or natural gas - a reverse of the situation in earlier decades. From 2000 to 2005, coal extraction expanded at an average of 4.8 per cent per year compared to 1.6 per cent per year for oil: although world natural gas consumption had been racing ahead in past years, in 2005 it actually fell slightly.

Looking to the future, many analysts who are concerned about emerging supply constraints for oil and gas foresee a compensating shift to lower-quality fuels. Coal can be converted to a gaseous or liquid fuel, and coal gasification and coal-to-liquids plants are being constructed at record rates.

This expanded use of coal is worrisome to advocates of policies to protect the global climate, some of whom place great hopes in new (mostly untested) technologies to capture and sequester carbon from coal gasification. With or without such technologies, there will almost certainly be more coal in our near future.

According to the widely accepted view, at current production levels proven coal reserves will last 155 years (this according to the World Coal Institute). The US Department of Energy (USDoE) projects annual global coal consumption to grow 2.5 per cent a year through 2030, by which time world consumption will be nearly double that of today.

A startling report: less than we thought!

However, future scenarios for global coal consumption are cast into doubt by two recent European studies on world coal supplies. The first, Coal: Resources and Future Production (PDF 630KB), published on April 5 by the Energy Watch Group, which reports to the German Parliament, found that global coal production could peak in as few as 15 years. This astonishing conclusion was based on a careful analysis of recent reserves revisions for several nations.

The report’s authors (Werner Zittel and Jörg Schindler) note that, with regard to global coal reserves, “the data quality is very unreliable”, especially for China, South Asia, and the Former Soviet Union countries. Some nations (such as Vietnam) have not updated their proved reserves for decades, in some instances not since the 1960s. China’s last update was in 1992; since then, 20 per cent of its reserves have been consumed, though this is not revealed in official figures.

However, since 1986 all nations with significant coal resources (except India and Australia) that have made the effort to update their reserves estimates have reported substantial downward revisions. Some countries - including Botswana, Germany, and the UK - have downgraded their reserves by more than 90 per cent. Poland’s reserves are now 50 per cent smaller than was the case 20 years ago.

These downgrades cannot be explained by volumes produced during this period. The best explanation, say the EWG report’s authors, is that nations now have better data from more thorough surveys. If that is the case, then future downward revisions are likely from countries that still rely on decades-old reserves estimates. Altogether, the world’s reserves of coal have dwindled from 10 trillion tons of hard coal equivalent to 4.2 trillion tons in 2005 - a 60 per cent downward revision in 25 years.

China (the world’s primary consumer) and the US (the nation with the largest reserves) are keys to the future of coal. China reports 55 years of coal reserves at current consumption rates. Subtracting quantities consumed since 1992, the last year reserves figures were updated, this declines to 40 to 45 years. However, the calculation assumes constant rates of usage, which is unrealistic since consumption is increasing rapidly. Already China has shifted from being a minor coal exporter to being a net coal importer. Moreover, we must factor in the peaking phenomenon common to the extraction of all non-renewable resources (the peak of production typically occurs long before the resource is exhausted).

The EWG report’s authors, taking these factors into account, state: “it is likely that China will experience peak production within the next 5-15 years, followed by a steep decline.” Only if China’s reported coal reserves are in reality much larger than reported will Chinese coal production rates not peak “very soon” and fall rapidly.

The United States is the world’s second-largest producer, surpassing the two next important producer states (India and Australia) by nearly a factor of three. Its reserves are so large that America has been called “the Saudi Arabia of coal”. The US has already passed its peak of production for high-quality coal (from the Appalachian Mountains and the Illinois basin) and has seen production of bituminous coal decline since 1990. However, growing extraction of sub-bituminous coal in Wyoming has more than compensated for this.