Central power generation, efficiency

Fig. 1 Efficiency of central power generation. (View this art in color at www.dekker.com.)...

The consumer wants to save money on the combined electricity/gas bill. A more efficient SOFC system with a power generation efficiency which is higher than that of a central power plant will meet this need. 

Example 5.1 A central power plant, rated at 800,000 kW, generates steam at 585 K and discards heat to a river at 295 K If the thermal efficiency of the plant is 70 percent of the maximum possible value, how much heat is discarded to the river at rated power ... 

Another approach to increasing power plant efficiencies is to use a nonther-mal conversion method for power production, such as fuel cells. Fuel cells rely on electrochemical conversion of the chemical energy in the fuel to electric power. In the cogeneration mode, these systems have been reported to be operable at overall efficiencies as high as 85% (Schora, 1991). Large-scale power plants based on fuel cells have not been developed yet and are not expected to be available for generating central station power until well into the twenty-first century. 

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