154 



MULTIPLE PURPOSE RIVER DEVELOPMENT 



Our analysis of the comparative efficiency of the alternative Hells 

 Canyon dams employed an estimate of $41.58 as the value of prime 

 power per kilowatt. We also assumed power output consistent 

 with operations under conditions of complete hydraulic and elec- 

 trical integration for a system of which the Middle Snake is but a 

 part. While both of these assumptions are appropriate for evaluat- 

 ing the different plan under public operation, where social costs 

 and gains are compared at the margin, they are not very useful for 

 analyzing the problem facing a private firm in reaching an invest- 

 ment decision. 



TABLE 25. Comparative Costs of the Two-Dam and Three-Dam 

 Alternatives, Assuming Idaho Power Company 

 Construction and Operation 



Alternatives ($ thoi 

 Two Dams Thr 



196280 i 



Interest and amortization *• 10,752 11,055 



Interim replacement •= 893 1,074 



Federal corporate taxes ** 6,379 6359 



State and local taxes ' 2,944 3,027 



Operation and maintenance * 1,625 1,666 



Insurance « 196 202 



Total average annual costs 22,789 23383 



Increment of average annual costs of three dams 



over two dams 794 



" Construction costs taken from FPC Staff Brief, Appendix B, Table 14, at 5 

 per cent interest during construction, and exclusive of provision for downstream 

 generators. 



•^ Interest at 5 per cent, amortization period of fifty years (ibid.. Appendix B, 

 p. 94). 



<^ Ibid., Appendix B, pp. 87-88. 



•• Investment at 3.25 per cent (see note to Chapter V for explanation). 



* Investment at 1.5 per cent (note to Chapter V). 



* FPC, Staff Brief, op. cit. Appendix B, p. 89. 

 8 Ibid., Appendix B, p. 88. 



The at-site value of power was derived by the FPC staff by esti- 

 mating the lowest cost of alternative non-hydroelectric power, on 

 the assumption that the alternative thermal capacity would be 



