Over the past week or two we have seen a synchronised disruption to the world's coal - especially thermal coal - supply chain.

Not synchronised in terms of all the players acting in concert, but wheels coming off all at the same time.

Floods in Queensland blocking rail lines and damaging mining equipment, the freezing weather in China, transport problems in Indonesia and the power crisis in South Africa - all these have combined to put the squeeze on thermal coal supplies.

China's Transport Ministry ordered a temporary stop to exports to ensure adequate supplies to domestic users and there have been news reports that the National Development and Reform Commission may ban coal exports in February and March to safeguard adequate coal and power supplies for the domestic market.

The China ban saw some spot prices go to $US94 ($A105) a tonne. But then the price kept taking off with Reuters reporting that a February cargo out of Richards Bay was offered to a potential buyer at $US135/t.

On Tuesday the news agency posted a report that Indonesia's largest coal miner, PT Bumi Resources, was predicting that the price could go to $150 in the near future.

Newcastle coal has already seen a sharp spike - rising from $75/t in October to $90/t in January.

Then, on top of all this, the chairman of the Indonesia Coal Producer Association, Soedjoko Tirtosoekoetjo, warned that heavy users of coal in north Asia would not be able to rely on Indonesia; rising domestic demand was putting pressure on its mines.

All this might seem just an unfortunate conjunction of events but for an article in the New Scientist magazine. This is a journal that should be taken seriously: after all, last year it sent up a distress flare to alert us to the looming shortage of certain rare metals, particularly indium.

The magazine questions the very basis of our energy dependence assumptions that there is enough coal to last us for centuries.

The article argued there was a case that coal shortages were not just a matter of infrastructural bottlenecks.

It cites the case of Newcastle and the fact that up to 80 ships at a time can lie off the port waiting to be loaded with coal. These delays had been getting worse since 2003 but not just because of the port's limited capacity.

Then it got to the point: "Gnawing doubts are also beginning to emerge about the supply of coal, not just in Australia but worldwide, and not only because of logistics but also because of geology. In short, coal may be running out."

In other words, and just like oil, most of the big deposits have been found and many of them are reaching depletion. The United States passed its peak production of all types of coal in 1990.

You can bet your boots that China will move to conserve its supplies, possibly invoking the same export penalties on coal as it has on several specialist metals.

Just as we were adjusting to the concept of "peak oil", New Scientist invokes the spectre of "peak coal".

Look around and you see coal producers and users scrambling to grab deposits that will eventually secure additional supply.

Straits Resources, for example, has expanded its coal hunt to Madagascar. Tata Power of India has taken a 30% stake in Indonesia's two largest coal mines to supply a new power station at home.

China has in recent years exported between 80 million tonnes and 100Mt of thermal coal. But it brings on-stream a new coal-fired power station each week; Japan is building 10 new coal power plants.

How can China sustain its export levels - and where is Japan going to get the thermal coal it buys from China?

So it is time to see coal as well as gold and oil as fundamental stocks to own.

The Chinese have already tumbled to this: this week, China Coal Energy said its initial public offering on the Shanghai Stock Exchange had brought in $433 billion (yes, billion) in subscriptions. Chinese punters oversubscribed for the stock by 122 times.

The Guardian has reported that stockpiles of coal at Chinese power stations have reached their lowest ever, and more than 80 plants were at "alert levels".

If you have any doubts that thermal coal is going to be anything other than an increasingly prized commodity, just think how many air-conditioners are whirring away in Asia; and how many more will start whirring in the new apartment towers being built all over China.

People might cut back on eating out, buying furniture, and so on. But they won't be without cold air in the height of the Asian summer.