Issues: Coal Reserves

I am interested in looking at the future of energy. From an engineering perspective, providing electricity and the power for transportation is one of the great accomplishments in history. But it's clear that 100 years from now, it won't be done the way it is today. So I am curious about how it will be done, particularly for transportation. First I wanted to see where we are with the current methods, like fossil fuels. Coal provides about half of the electricity for the US and for the world, so let's see how much coal we have left. Sorry if this is a little long, but there was plenty of interesting information. Also, I am just trying to answer the question of how long would coal last if we kept using it, I am not trying to get into any discussions about political or environmental impact. At least not yet.

There is more energy available in coal reserves than in oil or natural gas. Coal reserves are also more widely distributed between countries of the world than other fossil fuels. Getting a handle on how much coal is left for the world to use is not simple. The most widely agreed upon number is around 900 billion tons, from the U.S. Energy Information Administration, the World Energy Council, and BP's annual report on energy assets. This number is the amount of "Proven" reserves, which is not the total amount of coal in the ground, but the amount that makes economic sense to dig up under current conditions.

Where is the Coal?  (Gunnmap)

In reality there are vast amounts of coal (and oil and natural gas) that we will never use. The EIA estimates that in the United States alone, there are between 2 and 4 trillion tons of coal in the ground, but only about 500 Billion tons are technologically feasible to mine, and only half of that is economically feasible. These reserves change over time – up from new discoveries of reserves, better technology to put more reserves in play, and the addition of more economically feasible reserves as coal prices increase. The 900 billion tons has been steady for a while, but it is more likely an overestimate than an underestimate, because reserve numbers are not updated very well. China, for example, is still using reserve numbers from 1992, despite having mined about 20% of that amount since then. In all of our time so far, humans have burned about one quarter of the coal that would make up our reserves today. Europe is down to less than half of what it started with. But given a need for coal and no cost-effective alternative (a poor assumption), it is reasonable that we could mine twice the amount we current consider reserves.

None of that answered the question of how long the questionable amount of coal reserves will last. If we assume those 900 Billion tons are all we can mine, then it will last about 120 years at current production. But worldwide coal production and usage has been climbing rapidly, at a little over 5% per year for about the last ten. If that continues, then the world will run out in 40 years.

That scenario is unlikely, even without a push towards renewable electricity. The growth will start to plateau at some point. But some growth will happen, and 120 years is very optimistic, even figuring we double the potential reserves with new finds. Any estimates that claim 250 years of coal reserves are either overly-optimistic, or are considering only the United States.

The United States not only has the largest coal reserves in the world (Russia is second), but is mining relatively slowly (though is still the #2 producer). At current rates, the US has a little over 200 years before current reserves are exhausted. Compare that to China, which has the third largest reserves, but is mining almost three times more than the US, meaning that they have only 41 years at current rates. The EU has 51 years. As other countries begin to run out, production in the US might pick up for exports, so it makes sense to analyze this globally.

All of this might be a needless way looking at coal production, because economic factors might be too important for the world to ever end up completely running out of coal. There is the idea of production peaks (see peak oil) for finite resources, where, well before a resource runs out, it climbs to a maximum production, then falls over time until the resource is depleted. Now, the reasons for this are both physical and economic, and honestly beyond me. A peak in coal production may happen well before 2050, followed by anything from a global crisis - if the need for coal stays but supply drops - to no problems - if the world smoothly switches to other forms of energy as production declines. A common estimate for this coal peak is 2025, but predictions vary wildly, and peaks are difficult to predict (I.E. the oil peak may have already happened, but we won't know for sure until we see a few more years of data).

So, regardless of any peak, somewhere between 60 and 80 years of coal is likely available if a major shift is not made in coal usage. But a major shift is what I am concerned about. Oil and natural gas reserves will run out well before coal, so an option to keep in mind, along with other alternatives, is to use coal to replace other fossil fuels, with coal-to-methanol or coal gasification. I might write about them later, but it appears that the numbers don't support these methods. Replacing oil with coal will reduce the reserves of coal faster and still put the year of depletion around the same time for either scenario. It may be worthwhile to discuss these processes from a standpoint of energy independence, so the US could cut down on oil imports, and again, I am ignoring (for now) everything about CO2 emissions. I'll get to some of those topics in another post.

Links: Disappearing Amphibians, Rabid Vampire Bats, and Plans for Cleaner Energy

Amphibians have been declining world-wide over the last several decades due to a mixed cocktail of pollution, habitat loss, climate change, and the uncontrolled spread of a devastating infectious fungus. One such amphibian is the elusive Golden Toad, which has not been seen since 1989. Now, scientists have begun a world-wide search for 100 of these frogs that have disappeared, hoping to find residual populations that can be protected.

Global hunt for "extinct" species of frogs.


Peru is battling a vampiric horror! Mainly vampire bats, bats that bite and drink the blood of sleeping mammals, that are infected with a strain of rabies. Four children have died after being infected by these animals, and over 500 people in total have been vaccinated after being bitten.

Peru battles rabid vampire bats after 500 people bitten.


And this week is big news for alternative energy... or at least plans for the next 20-or-so years. Research in nuclear power puts plants around the world by 2030 and a recycling idea that would negate the need for dealing with radioactive wastes! On the other spectrum, research into biodiesels that are made from plant-grown micro-algae claims to be able to produce sustainable and cleaner energy in 10 to 15 years, eventually eliminating the need for fossil fuels! Whether we can afford it is another aspect all together.

Scientists outline a 20-year master plan for the global renaissance of nuclear energy

Industrial production of biodiesel feasible within 15 years, researchers predict.