Date : 01/01/2022
Efficiency is the output energy to input energy into 100%.
We calculate efficiency because as much input energy as possible should be transferred to a useful energy store and to see how it can utilize the stored energy.
Firstly,we measure the following dimensions:
Diameter of evacuated tube = 5.5 cm
Length of evacuated tube = 174cm
Area of one evacuated tube collector= l * b
=5.5*174 = 957 cm2
But here total 32 evacuated tube
total area of evacuated tube collector= 957*32 =30624cm2 =3.06m2
Temperature of water at 9am= 42°C
Temperature of water at 5pm=48°C
Capacity of storage water tank = 500LPD
energy in 1m2 = 813
Input = Total area of ETC× Energy in 1m² ×Time
= 71.648 × 10⁶
Output= Capacity of storage tank × 4.186 × Temperature difference
= 500 × 10³ × 4.186 × 6
= 12.558 × 10⁶
Efficiency of solar water heater= Output/Input
= 12.558 × 10⁶ / 71.648 ×10⁶
The efficiency of calculated solar water heater is 17%.This efficiency is very low because the dust on the evacuated tube was not cleaned.
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