Heat Rate                 Waste Heat to     
         (millions      nt         Cooling Water     
         of J/KWH)              (millions of J/KWH)  

 1930      20.89      17.24            14.16         

 1940      17.30      20.81            11.11         

 1950      14.80      24.33            8.98          

 1960      11.35      31.72            6.05          

 1962      11.14      32.33            5.87          

 1964      11.04      32.62            5.78          

 1966      10.99      32.77            5.74          



Best fossil-fuel plants operate at about 40% (considered to be about limit). Nuclear plants presently do not exceed 33% (metal strength).

Heat wasted to cooling water is less than the "waste heat" portion of the efficiency equation because of in-plant and stack losses. these losses estimated as 15% of thermal input. Therefore, for fossil-fuel plants,

Heat to cooling water (J/KWH) = 0.85 * (Heat Rate) - 3.6 *10-6

For nuclear plants, in-plant losses are about 5%.

Heat to cooling water (J/KWH) = 0.95 * (Heat Rate) - 3.6 *10-6

Comparison of waste heat for the two types.

fossil-fuel plant, nt = 40%

nuclear plants, nt =33%

Thus, advent of nuclear plants may increase by over 60% the amount of heat rejected to to cooling water per KWH.

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