Monday, March 05, 2007

Coal Fired Cars?

Mr Bush has called for the United States to produce 35 billion gallons of alternative fuel by 2017. Since one U.S. gallon = 3.875 litres and there are 159 litres to a barrel of oil, this amounts to 35 x 10^9 x 3.875/159 = 8.53 x 10^8, or 853 million barrels. The U.S. daily fuel bill is around 20 million barrels = 7.3 billion barrels per year, or around one quarter of the world's total. Therefore at best this would meet 8.53 x 10^8/7.3 x 10^9 = 12% of the amount of fuel used in the U.S. Now according to an article in this month's "Chemistry World", if the entire U.S. corn crop were converted into bioethanol, that would meet that 12% target; hence if any food is to be produced from corn at all, the amount of the U.S. fuel produced using biofuels would be far less than even this 12% figure. The same argument applies to the U.K. and to all nations. Pressure on imported fuels has never been greater, and now China and India are investing heavily in oil companies across the world including South America (e.g. Venezuela) and Norway. The alternative source of alternative fuel on the grand scale is coal, which can be converted to liquids by various methods. The best of these in terms of overall utilisation of thermal energy are the combined cycle plants, which produce both liquids (hydrocarbons) and electricity; however, simple coal-to-liquids plants are cheaper to build, and in principle could convert much of the enormous reserves of coal that are held in the U.S. into fuel, thus reducing the demand on imported fuel, especially from the Middle East.
This sounds promising, but it is not necessarily good for the planet. Indeed, it is estimated that altogether, fuel from coal will cause twice the amount of CO2 that would be produced by an equivalent quantity of gasoline etc. obtained by refining crude oil. It is suggested that this problem might be fixed by new technology but this seems to refer to sequestering CO2 rather than using the coal more efficiently in the first place, e.g. in combined cycle plants. However, it looks as though there could be a generation of coal-to-liquids plants built in the U.S., and nine of them are planned in Illinois, Pennsylvania and Wyoming, to be inaugurated in 2009. If all nine of them are built, they could produce around 3 billion gallons of fuel per year, which is way short of the president's goal of 35 billion gallons (less than 1% of the total used in the U.S.). It is thought that if federal tax incentives and state subsidies are made to kick-start this new industry, by 2025, 40 billion barrels per year could be produced by coal liquefaction - which is about 10% of the annual fuel demand forecast. Simple arithmetic suggests that to produce this amount would require 40/3 x 9 = 120 new plants.
It is interesting the way economists think though isn't it? By that stage there will be probably just one third of the existing oil reserves left, and so where will the additional oil (90%) come from physically, never mind its market price? To maintain the U.S. (and the West in general) at its current lifestyle would need an awful lot of coal liquefaction, perhaps from 1,200 plants which have yet to be built in the U.S. alone. All practical analyses seem to arrive at the same conclusion, that whatever else we may implement (nuclear, as much renewable energy etc. as is possible), current amounts of fuel cannot be met in the future and alternatives of transportation-economy are the only solution to this great dilemma. I think we have much to learn from the Centre for Alternative Technology (CAT), that I discussed in the article immediately previous to this. We cannot solve our problems using balance-sheet economics (cost per barrel) and we need to review the amount of fuel that can be physically got, from whatever sources - and since that quantity, as deduced by all means I can find, falls well short of current levels (let alone predictions of growth), this will necessitate re-localising society.


Anonymous said...

First of all, why is this comment box in the French language?
Second, my comment.
Dr Diesel's original patent was for an engine which operated by burning powdered coal in a cylinder operating on a compression/ignition cycle. His original engine can be seen in the MAN museum in Augsberg (MAN was his manufacturer). I understand that he had troubles with the practicalities of the powdered fuel system and turned to oil instead. But now, after 100 years, would it not be worth while for someone to re-investigate Diesel's powdered coal idea? Might it not require less energy than coal liquifaction?

Professor Chris Rhodes said...

It reads in English here? I like your comment, however! Yes, maybe it would indeed require less energy that coal liquefaction. I'll look into this.


Chris Rhodes.

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