Power Generation and Distribution. 



475 



III. 

 Cost per B.H.P. hour at 50% Load Factor with direct transmission. 



IV. 

 Cost per B.H.P. at 50% load factor with local electrical transmission. 



Total cost per B.H.P. 

 hour ... ... ro5d 



o-88d 



076d 



o-66d 



The conclusions to be drawn from comparing Tables A and B 

 are the following : — 



(a) That for fairly steady loads during ordinary factory 

 hours (25 per cent, load factor), it is cheaper for the 

 Power-User to employ his own engine applied direct 

 — that is to say, without the intervention of electrical 

 transmission — even below 125 H.P., which is estimated 

 to cost o.QQd. per B.H.P. hour, and 1000 H,.P. o.65d. 

 per B.H.P. hour against i.o6d. per B.H.P. hour 

 purchased. 



(b) That for ordinary factory hours, where the diversity 

 factor would justify electrical transmission in any 

 case, a private plant of 250 H.P. and upwards can 

 compete successfully with the assumed purchased 

 supply of energy. 



(c) That for a 50 per cent, load factor a local 500 H.P. 

 engine, applied to its load direct, would cost less than 

 the assumed purchase of electric energv. 



{d) That for a 50 per cent, load factor, when the 

 diversity factor justifies electrical transmission in any 

 case, a 1000 H.P. private plant (or larger) can success- 

 fully compete with the assumed purchased supply, 

 after covering motor losses. 



