Pratap technical experience

  Question= A power station having a maximum demand of 100 mw has a load factor of 30% and is to be supplied by one of the following schemes. (1) A steam station in conjunction with a hydro - electric station, the latter supplying 100×10⁶ kwh per annum with a maximum output of 40 mw.  (2) a steam station capable of supplying the whole load .  (3) a hydro station capable of supplying the whole load. Compare the overall cost per kwh generated ,??  assuming the following data . Solution= overall cost/kwh= (total annual charges for both steam and hydro station)÷ ( unit generated per annum) ,  » Total annual charges steam station =   • so, steam station , total annual cost= operating cost+annual interest and depreciation,  » operating cost= operating cost/kwh 5 paise × unit supplied by station,  » unit supplied by station = unit generated per annum - unit supplied by hydro station ,  » unit generated per annum = maximum demand × L F. × hours in a year, = 100 mw × 30% × 8760 hours , =

  Question= Compare the annual cost of supplying a factory load having a maximum demand of 1 megawatt and a load factor of 50% by energy obtained from (1) a private oil engine generating plant ? and (2) public supply ?  (1) detail of private oil engine generating unit =capital cost=RS 12×10⁵ , cost of repair and maintenance = RS 0.005 per kwh generated , cost of fule = RS 1600 per 1000 kg , interest and depreciation = 10% per annum, fule consumption = 0.3 kg/kwh generated, wages = RS 50,000 per annum,, (365days×24 hours = 8760 hours)  (2) public supply company , RS 150 per kw of maximum demand plus 15 paise per kwh.  Solution=  1 st compare = total annual running charges = annual cost of fuel + annual cost of repair and maintenance + annual wages +  annual interest and depreciation . • annual cost of fuel = annual fule consumption × RS 1600 per 1000 kg ,  » annual fule consumption = unit generated per annum  × fuel consumption (0.3 kg/kwh) ,   » so, units generator per annum = M D.