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2. LPG GAS
125 LPD
a) system capacity
b) Average output temperature 65 c
c) Average input temperature 25 c
d) Total heat gain System capacity temp difference=125
40=5000 kcal
e) Approximate total cost Rs 22000/-
f) Efficiency 80%
g) Operational days in year 300
h) calorific value of oil 11900 kcal/kg
i) Purchase cost Rs 32/- per kg
j) Specific gravity of oil 0.54
k) Oil required per day Heat gain /(calorific value specific gravity
efficiency)=5000/11900 0.54 0.8=0.97
kg/day
l) Savings per day 0.97 32= Rs 31.04/-
m) Savings per year 31.04 300 =Rs 9312/-
n)Payback period
o) payback period 2.36 years
3.ELECTRIC GEYSERS
a) System capacity 125 LPD
b) Average output
temperature
65 c
c) Average input temperature 25 c
Net cost /Savings per year
22000 /9312
d) Total heat gain (kcal) System capacity temp difference= 12540=5000
kcal/day
e)Total heat gain (kwh/day) 21000/3600 kwh/day
f) Savings in electricity 5.83 kwh/day
g) Approximate total cost Rs 22000/-
h) cost of electricity Rs 4.50 per unit (kwh)
i) Saving cost Unit saved cost per unit =5.88 4.50 =Rs 26.23/-
j) Saving per day Rs 26.23
k) Saving per year 26.23 300=Rs 78691/-
l)payback period
Total cost / saving per year
=22000/7869 = 2.79 year
90 JBNB (Vol. I ) Issue I January’2013