Carbon fuels free energy

Some environmentalists have also touted natural gas as a way station on the road to a hydrogen fuel (carbon dioxide-free) economy. As seen in Table 1, per unit of energy released, natural gas generates about 23 percent less carbon dioxide than gasoline and about 30 percent less than heavy fuel oil. This is helpful in reducing greenhouse emissions, but the other excellent properties of natural gas are even... 

Hydrogen production holds renewed promise for nuclear energy, as nuclear-based hydrogen production can provide an essentially carbon emissions-free source of hydrogen, significantly reduce dependence on fossil fuels, and open a new area of application for nuclear energy that may eventually exceed the use of nuclear power for electricity. 

Thermodynamic calculations presented here are based on Gibbs free energy minimization and were carried out using HSC Chemistry. The equilibrium amount of each species that is formed is normalized on the basis of one mole of n-Ci6, a model compound for diesel fuel, fed to the reactor. Carbon formation is a function of both the S/C ratio and reforming temperature. Figure 17 shows the minimum amount of S/C ratio thermodynamically required for carbon-free SR of n-Ci6 at a given temperature. Carbon-free operation of n-Cig is thermodynamically possible above the curve. Higher temperatures and S/C ratios inhibit carbon formation. 

Transitioning towards a carbon-free energy system is all the more timely as the production of fossil fuels is anticipated to peak in the 21st century owing to the steadily rising production rate and unavoidable resource limitations peak-oil or plateau around 2015-2020, peak-gas around 2030 and peak-coal around 2060 (if exploited with no restriction, which would lead to an unacceptable C02 concentration of 600 ppm in the atmosphere). 

Energy from varied fuel stocks and production processes, in particular the potential for carbon free energy... 

Fires. Combustion of any kind produces toxic particulate matter, smoke. The combustion can be natural such as a lightning-induced forest fire or unnatural such as the burning of fossil fuel for energy production, a petroleum refinery or plastics warehouse fire)22-23 In addition to particulates, fires produce PAHs, carbon monoxide, organic and inorganic cyanides, and free radicals that are toxicJ24-25 ... 

A longer-term need is to eliminate unbumed hydroearbon (UHC) and CO2 emissions. Gas turbines aeeount for 20% of U.S. CO2 emissions, whieh is a signifieant fraction of the total current CO2 emissions. This number will increase as natural gas turbines replaee older coal-fired steam generation plants. The use of hydrogen-blended hydrocarbon fuels thus provides both a solution to the immediate need for NOx reduction, and also provides a transition strategy to a carbon free energy system in the future. 

Chemotrophs derive free energy from the oxidation of fuel molecules, such as glucose and fatty acids. Which compound, glucose or a saturated fatty acid containing 18 carbons, would yield more free energy per carbon atom when subjected to oxidation in the cell See Figure 14.10 on page 381 for a comparison. 

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