102 



Indiana University Studies 



Fuel and water costs represent the cost of these materials 

 laid down at the plant ready for use. 



Oil, waste, and supplies include all supplies used about the 

 plant that are not directly chargeable to repairs and maintenance. 



Power costs thruout the stone belt, taking into account the 

 above factors, vary widely. The figures cannot be brought down 

 to a definite cost per horse-power per hour, until the load factor 

 of the plant is determined. The load factor is the yearlj^ output 

 of power divided by the rated horse-power, times 24, times 365. 

 In fact, if an operator knew the exact amount of power used per 

 year, the problem would become the yery simple one of dividing 

 the yearly cost of power by the horse-power used. Where 

 electrical equipment is in use these figures are easily calculated. 

 Where calculations were made the cost of power in this district 

 was found to vary from 1.65 to 4.23 cents per horse-power per 

 hour. Calculations were made on a few plants only, and 

 are given merely to show in a general way what the present 

 situation is. These figures when calculated on the Kilowatt 

 basis become from 2.21 to 5.67 cents per kilowatt per hour. A 

 number of manufacturing companies that specialize in the types 

 of power machinery used in quarry and mill work were asked 

 to submit figures on the cost of power in plants w^here their ma- 

 chinery is in use at the present time. In answer to a letter ask- 

 ing for data on the cost of power in a 100-kilowatt plant, or plants 

 of nearly that power, the following data were submitted on the 

 cost of power in a quarry at present in operation in the Oolitic 

 stone belt in Kentucky. Altho the plant is larger than the one 

 I suggested, the data will show what good practice in the stone 

 belt could accomplish. The figures given represent a low power 

 cost in this kind of service, but this results from the high average 

 load, the low cost of labor, and the fact that no machinery is 

 held in reserve. The letter mentioned is as follows: 



It would require a 16 by 20 "J" Corliss engine direct connected to a 

 200 r.p.m.; a 200 K.V.A., 60-cycle direct-connected alternator and belted 

 exciter for same, a water-tube boiler with 2,000 square feet of effective 

 heating surface in the tubes, a feed-water heater, two boiler-feed pumps, 

 a guyed steel smoke stack, etc., and our estimate of cost is as follows: 



The engine delivered and erected S3 , 400 



Foundation for engine 275 



One direct-connected alternator, 200 r.p.m. and exciter delivered 



Switchboard and cables to connect switchboard to alternator and 



and erected 



2,600 



exciter 



900 



