COST COMPARISONS 65 



equipment needed to generate power for the extra losses, 

 and this has been done at the figure of $100 per Kw. It 

 is obviously incorrect to capitalize the income which 

 might have been obtained from the sale of this extra 

 power, since it is generated in bulk, usually not near a 

 city, and is sent into the transmission lines and lost 

 there. As is well known, the greater part of the cost of 

 power sold to a customer, especially from a water-power 

 plant, is in its distribution and regulation. 



The saving due to the constant-voltage system for 

 the 6o-mile line, as tabulated, is not large, and at first 

 sight it might appear that for a distance of 60 miles or 

 less synchronous motors are not worth installing in con- 

 nection with a transmission line. Such, however, might 

 be a quite erroneous conclusion. Before making a final 

 decision, the other items should be taken into account, 

 namely, the saving in land, the possible use of lower 

 voltage involving saving in insulators, transformers, and 

 circuit breakers, the operating advantage of controlling 

 the voltage at the place where the power is used instead 

 of at some distant point by means of long-distance tel- 

 ephone, and, finally, the advantage of having constant 

 voltage at all points so that power can be sold under the 

 best conditions at generating, receiving, and intermediate 

 stations. When all these advantages are considered, 

 there are few cases where synchronous motors cannot be 

 economically used in the design of a transmission system, 

 or where they cannot be profitably applied to a heavily 

 loaded line already constructed. 



It is to be noted that the voltage at the receiver end 

 of the constant- voltage lines is always taken at a lower 

 figure than at the generator end, because this gives the 



