System capacity | 125 LPD |
Average output temperature | 65 deg. C. |
Average input temperature | 25 deg. C. |
Total heat gain | System cap. x temp. difference |
= 125 x 40 kcal = ,5000 kcal | |
Approx. total cost | Rs. 25,000/- (US$1=@Rs.55.00) |
Boiler efficiency | @ 80 % |
Operational days in a year | 300 |
Calorific value of oil | 10280 kcal/kg |
Purchase Cost | @ Rs. 30- per liter |
Specific gravity of oil | 0.8 |
Oil required per day | = Heat gain/ (calorific value x sp. gr. x boiler efficiency) |
= 5000/ 10280 x 0.8 x 0.8 | |
= 0.76 liters | |
Saving per day | = 0.76 x Rs. 30/- = Rs. 22.80 |
Saving per year | = 22.80 x 300 = Rs. 6840/- |
Payback period | = Net cost / saving per year |
= 25,000/ 6840 | |
Payback period | = 3.65years |
Payback period with subsidy | 2.77 years |