The objective of the project is to reduce the huge amount of water wasted in TAPMI. People waste the cold water while waiting for the hot water as solar geyser is centrally located and the water in the pipes becomes cold if continuous usage is not there. A water recirculating system idea has been developed to recirculate the cold water to reduce wastage and waiting time for hot water.

1. Water Waste Reduction
in Solar Heating System
By:
Ayas kanta Mohapatra
Guide:
Prof. Vidya Pratap
Prof. Seena Biju

2. Background
• Hot water is stored in solar tank and then
flows through pipelines
• However, the water loses heat if not used for a
longer time
• So we have to waste the cold water till we get
hot water
• This objective of this project is to reduce the
amount of water wasted in this way.

3. Assumptions
• Only prototypes have been explained
• Major amount of water is wasted in the morning
• All the water present in the pipes in the morning are wasted
• The volume of the pipe is equal to the water wasted in the
morning
• Four (35m*45m*25m) building has been considered
Limitations
• Confidential data has been removed
• Only prototypes have been explained

4. Water Wastage
Diameter of Pipe 0.025 meter
Total Length of all pipes in a single building 1080 meter
Volume of pipes in a single building 0.530357143 cubic meter
Total No. of buildings 4 numbers
Total volume of pipes 2.121428571 cubic meter
Monthly waste 63.64285714 KL
560.4220286 Gallon
Amount of water wasted = more than 63KL per month

5. Current Pipeline Design

6. Alternative – 1
• Direct water recirculation through an
additional pump

7. Cost Analysis
Alternatives Equipments Specification Unit Cost Requirement Cost
Alternative 1
Centrifugal Pump
1 HP, 5m Head,
1500 rpm 6500 1 6500
Timer 320 1 320
Cable 3 core, 2.5 sqmm 30 10 300
RCCB 2 Pole, 10A 1700 1 1700
Ball Valve 1 "(25 mm) 211 1 211
CPVC Pipe 1 "(25 mm) * 16' 463 34.85 16135.55
CPVC Tee 1 "(25 mm) 38 24 912
CPVC Elbow 1 "(25 mm) 30 5 150
Union 1 "(25 mm) 95 2 190
Labour
Total 26418.55

8. Alternative – 1
• Pros
– Economic
– Automatic system
– Independent system
• Cons
– More electricity consumption
– Cavitation problem may occur
– NPSH issue may be there

9. Alternative – 2
• Water Recirculating System using an external
pump

10. Cost Analysis
Alternatives Equipments Specification Unit Cost Requirement Cost
Alternative 2
Centrifugal Pump
5 HP, 40m Head,
3000 rpm, FR=
150.876 gallon/
minute 14000 1 14000
Timer 320 1 320
RCCB 2 Pole, 10A 1700 1 1700
Cable 3 core, 2.5 sqmm 30 20 600
Ball Valve 1 "(25 mm) 211 2 422
CPVC Pipe 1 "(25 mm) * 16' 463 34.85 16135.55
CPVC Tee 1 "(25 mm) 38 24 912
CPVC Elbow 1 "(25 mm) 30 7 210
Union 1 "(25 mm) 95 2 190
Concrete tank 2m*2m*2m 10000 10000
Labour *
Total 44489.55*

11. Alternative – 2
• Pros
– Independent system
– Semi-automatic system (with level sensor)
– Can be helpful during maintenance of tank
• Cons
– Expensive
• Concrete tank
• Pipeline layout
• Pump

12. Alternative – 3
• Water Recirculating System using the existing
pump

13. Cost Analysis
Alternatives Equipments Specification Unit Cost Requirement Cost
Alternative 3
NRV 1 "(25 mm) 300 1 300
Ball Valve 1 "(25 mm) 211 2 422
CPVC Pipe 1 "(25 mm) * 16' 463 34.85 16135.55
CPVC Tee 1 "(25 mm) 38 24 912
CPVC Elbow 1 "(25 mm) 30 5 150
Union 1 "(25 mm) 95 2 190
Concrete tank 2m*2m*2m 10000 10000
Labour *
Total 18109.55*

14. Alternative – 3
• Pros
– No additional pump required
– Can be helpful during maintenance of tank
• Cons
– Expensive
• Concrete tank
• Pipeline layout

15. Alternative – 4
• By insulating the hot water pipes

16. Cost Analysis
Alternatives Equipments Specification Unit Cost Requirement Cost
Alternative 4
K Flex Sheets
Part No.-
6RX038028, 1"
nesting (square feet
pricing) 350 100.10427 35036.49
Labour *
Total 35036.49*

17. Alternative – 4
• Pros
– Economic
• Cons
– Less efficiency

18. Suggestion
• Alternative 1
– To avoid higher instant investment
– Less labor cost
– Automatic system
– Independent system