Tuesday, May 26, 2009

End of An Age

With the renewed discussion of cap-and-trade and carbon taxes, I thought it a good idea to look at combustion energy at its most elemental level. Envision prehistoric man huddled around a fire, maybe ignited with sparks left over after a lighting strike or even a fire started by flint against stone. We have come a long way from such circumstances….and then again we have not. Fire is still the same as it was back when the mammoth roamed the range.

Combustion at the most basic level is a chemical reaction between a fuel compound and an oxidant. Paleolithic Dude used a hydrocarbon for his fuel compound - sticks and grass. The oxygen in the free air was the oxidant and of course, there was his trusty flint and rock for that initial spark. Fast forward to the present time for other more impressive examples. We have high performance engines that use highly compressed hydrocarbons such as gas and coal as fuel set off by spark plugs. The fuel is different but combustion engines today rely on atmospheric oxygen just like tens of thousands of years ago.

Then and now the chemical reaction yields a whole lot of by-products. Besides carbon dioxide and water we also get carbon monoxide, pure carbon or ash, and various nitrogen oxides. The less efficient the oxidant reacts with the fuel, the more by-products are produced. Atmospheric oxygen is just not very efficient.

Of course, these extra toxic emissions are what have got us into so much environmental trouble. Early man used combustion at the most elemental level - for its raw heat to prepare food and keep warm. Modern man has harnessed combustion to drive machines - power generators, industrial furnaces, cars, train engines. What we have not fully harnessed are the by-products of the chemical reaction. Maybe we would still be OK if our ancestors had spent more time hunting or something and less time around the home fires making more little hominids.

There have been some ideas - burn with abandon and sink the carbon dioxide into old coal mines (sequestration); tweak the combustion process to burn air more efficiently (fuel catalysts); strip off the carbon and burn pure hydrogen to yield only water vapor (hydrogen fuel cells); abandon combustion altogether by turning to alternative energy sources to drive machines (wind turbines). It seems we do not lack for scientifically grounded alternatives.

What we lack is economic clarity and perhaps the resolve to make tough choices. In my view, the best way to begin solving the problems of prolific combustion is set a price - the cap - and start bargaining - the trade. Finding equilibrium will be a messy process, but it seems global warming has brought to an end the number of archeological ages at our disposal for future debate.

More on the matters of resolve and economic clarity in the next two blog posts.

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