Economic of power generation 9
Question = A hydro electric plant costs RS 3000 per kW of installed capacity . The total annual charges consist of 5 % (F) as interest , depreciation at 2% (F) , operation and maintenance at 2 % (R) and insurance , rent etc , 1.5 % (R). Determine a suitable two part tariff if the losses in transmission and distribution are 12.5% and diversity of loads is 1.25 . Assume that maximum demand on the station is 80% of the capacity and annual load factor is 40% . What is the overall cost of generation per kWh ? Solution = overall cost /kWh = total annual charges ÷ unit reaching the consumer , » Total annual charges = annual fixed charges + annual running charges , » annual fixed charges (A F.C ) = capital cost of plant × ( interest % + depreciation % ) /100 , » capital cost of plant = let installed capacity of the station kW × plant cost per kW , » 100 kW × 3000 RS = 3 × 10⁵ RS , » interest % + depreciation % ) /100 = (5 +2 ) ÷ 100 » So , A F.C. = 3 × 10⁵ RS × ( 5+2 )/100 , = 21,000