Efficiencies of Fossil and Hydrogen Fuels

Efficiencies of Fossil and Hydrogen Fueled Transportation and Power Plant Processes 

H2 can also be used to capture carbon monoxide and COz in the combustion products. C02 can be converted into methanol. Each mol of C02 will require 3 mol of H2 to generate 1 mol of methanol (CH3OH). After recovering this methanol, it can be used as a fuel or fuel supplement, thereby reducing the need for burning coal, natural gas, or other fossil fuels, whereas the emission of C02 will also be reduced. 

As can be seen from Table 1.57, the efficiency of fuel cells is about double that of gas-burning internal combustion (IC) engines. Therefore, if fuel cells can be made at the same cost as IC engines, hydrogen fuel cell-based transportation is already cost competitive with gasoline-based transportation. Unfortunately, at this point in time, fuel cells are much more expensive, but that is likely to change as soon as mass production starts. 

As shown in Table 1.57, if the heat generated by the fuel cell is also recovered, the FC-based power plant efficiency can be nearly twice that of sub-critical fossil power plants. In addition to the improvement in efficiency, FC-based power generation is also superior to fossil fuel-based power generation, because there are no expenses associated with carbon recapture the only emission is distilled water. 

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