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Combustion:
energy production from carbon based fuels – the science![]() ![]() From the above we see that the use of fossil fuels can be improved in two related ways: improving the quality of emissions, increasing efficiency of energy output per unit mass of fuel. Carbon fuels which are not fossil fuels also offer an advantage (carbon neutral) because we are not adding to the current carbon by releasing carbon from millions of years ago i.e. in principle the carbon is “captured” by e.g. wheat, made into fuel which then releases back the same carbon. It does not however reduce the carbon level. The chemistry of combustion is well understood and developing methods of reducing emissions and improving efficiency are now a major focus for science and technology. Combustion is referenced in the links but in essence it follows the same basic equations as respiration. The physics however e.g. fluid mechanics of combustion is not covered in this section since it is the carbon chemistry which relates to the Stern Review more directly. Since the energy output from the combustion of a fuel reflects the net effect of making and breaking chemical bonds, it follows that different fuels provide different amounts of energy per unit even when fully combusted. These enthalpies of combustion are available in tables or can be calculated using Hess’s Law. For practical purposes of course, other factors come into play e.g. ease of production or extraction, cost, safety etc. |
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