The document provides information on solar powered water pumps and irrigation systems. It discusses:
- The basic operation of solar pumps, which only operate during daylight hours with variable output depending on sunlight.
- Design considerations for solar irrigation systems including water requirements, common irrigation applications like drip systems, and factors that determine the appropriate pump size like lift, pressure, and water volume needed.
- Examples of sized systems for different irrigation needs like greenhouses, fields, and flood irrigation, pairing the proper solar pump and array size to meet the desired water volume and lift.
2. 1. Basic of Solar Pumps
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Pumps only during daytime (more sunshine = more water)
Peak pump capacity only during midday
Variable speed and pump capacity
No fixed working point
Pump capacity depends on the size of the solar PV Array
Use Manual tracking system to increase output
3. 2. Water Volume and Lift
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The pump is defined by its volume [Q] and lift [H]
Volume = [Q = m3/day]
Max. flow [q = l/min]
Lift = [H = m]
Pressure [bar]
4. 3. Theory of Solar Irrigation
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5. Water requirements
6. Irrigation applications
7. Low pressure irrigation system
7.1 Micro Irrigation system
7.1.1 Filters and control
8. Traditional Irrigation (flooding)
9. Water volume management
5. 4. Water Requirements
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Water losses by plants and environment
Depends on crops and their development
Soil type
Latitude and altitude
Evapotranspiration losses
[ET = mm/day]
Evaporation = by open surfaces
Transpiration = by plants
high = < 6.5 mm/day (tropical region)
medium = 5 -6.5 mm/day
low = < 5 mm/day (moderate region)
e.g. 5.5 mm/day = 5.5 L/m2/day
6. 5. Irrigation Applications
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Compensation of water losses to optimize plant
growth
E.g. missing rain fall or uneven time distribution
Irrigation is possible for one plant or a field
Irrigation Technology
Modern irrigation: use pressurized systems
Sprinkler, Mini-sprinkler (spray), Drip systems
Traditional irrigation: use flood and furrow system
Irrigation timing: every day or in time sequences
(bigger volume)
7. 6. Low Pressure Irrigation Systems
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From 0.5 to 2 bars (reduced energy
requirements)
Low pressures means
more water outlets
more dense water distribution system
mainly use plastic pipe and outlets (emitters)
mainly fixed installation
8. 7.1 Micro Irrigation System
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Mini-Sprinkler (rotating droplet types)
Radius: 1-4 m / app. 1.5 bars
Mini-Sprayer (mist and spray types)
Radius: 1-3m / app. 1.25 bars
9. 7.1 Micro Irrigation System Drip System
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Drip Irrigation System
Drops at each outlet with app. q = 1 l/h
Integrated dipper
Attached adoptable dripper
Lay-flat tapes
Different outlets and row spacing
Outlets from 0.2m 0.33m form a humid band
Different wall thickness
Thickness defines time of usability
Pipe length depends on hydraulic limits
Equal water distribution (+/- 10%)
Different pipe or tube diameter available
Can be buried or attached at trees, e.g. vineyards
11. 7.2 Filters and Control
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Each system must have a filter (or several)
Otherwise the small outlets are blocked
Use bigger model to reduce hydraulic losses
Disc filter is better than screen filters
Clean the filters and pipes regularly
Control the irrigation system at the head unit
Install control and measurement devise for volume
and pressure
Add an inlet to the head unit for liquid fertilizer
13. 8. Traditional Irrigation (Flooding)
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Solar pumps lift water
Also from rivers and canals (floating version)
Water distribution through free outlet
Only lifting, no pressure required
High volume with minimum head
App. 1-6m only
15. 9. Water Volume Mangament
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Flow control only by volumetric meters (water
meter)
Time control not common in Solar-Irrigation-Systems
Manual control is standard (automatic optional)
Divide the irrigation plot in sections
Section (field) sizes must be equal
Irrigation plot must be rotated each time
Irrigation time (volume) due to crop development
and Evapotranspiration [ET]
Add 2nd drip-line for further crop development
and water requirement
16. IV. Application and Design
criteria
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10. BRIGHT Solar Pumps System and Irrigation
11. Design criteria
12. Examples for BRIGHT Solar Irrigations Systems
17. 10. BRIGHT Solar Pumps System and
Irrigation
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BRIGHT SOLAR pumps can easily be connected with
many irrigation systems
Match BRIGHT SOLAR pump with your irrigation system
(hydraulic requirements)
Low pressure systems are cost efficient (Drip)
Use water tank (min 3m) or direct connection
18. 11. Design Criteria Step 1
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Check your water source and look for limitations
Define lift and pressure [H] (TDH)
Select the crops (plants) and water needs [ET]
Define water volume [Q]
Select BRIGHT Solar Pumps
Determine size of the solar array
Select BRIGHT Solar Modules
Select BRIGHT SolarTracker
19. 11. Design Criteria Step 2
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Determine low pressure irrigation system (Drip)
Calculate hydraulic parameter (friction losses)
Use bigger filters and pipe diameters
Calculate max. drip line length (adopt field size )
Define drip line row spacing (distance) and out let
spacing
Select water meter and head unit for control and
management
Except variation in [Q & H] during the day (no water in
the night)
Use [Q = m3/day] and peak (max.) flow [q = l/min]
In summer more Solar Power = more water for irrigation
20. 12. Application Sizing and Examples (1)
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Example 1 (Greenhouse Irrigation):
1PM4SS-HR07 (900Wp -1 H.P. - Tracked)
17m続/day at 60m lift
Medium ET: 5mm/day (~5l/m族/day)
-> Drip irrigation area 2720m族 (using 80% eff.)
Greenhouse: 9m*55m = 540m族 -> app. 5 greenhouses
21. 12. Application Sizing and Examples (2)
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Example 2 (Field Irrigation):
2PM4-SS5-12 (1800Wp 2 H.P. - Not tracked)
Q = 46m続/day at H = 30m lift
High ET: 6.5mm/day (~6,5l/m族/day)
-> Drip irrigation area 5300 m族 (using 75% eff.)
Field area: app. 0.5 Ha
22. 12. Application Sizing and Examples (3)
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Example 3 (Flood Irrigation):
5PM6-SS30-2 (4800Wp 5 H.P. - tracked)
Q = 300m続/day at H = 15m
High ET: 5mm/day (~5l/m族/day)
-> Drip irrigation area 27000 m族 (using 45% eff.)
Field area: app. 2.5Ha
23. 12. Application Sizing and Examples (4)
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Example 4 (Flood Irrigation):
10PM6-SS42-4 (9600Wp 10H.P. - tracked)
Q = 500m続/day at H = 10m
High ET: 5mm/day (~5l/m族/day)
-> Drip irrigation area 48000 m族 (using 45% eff.)
Field area: app. 4.5 Ha
24. V. Final Conclusion
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1. Select low pressure irrigation system (micro irrigation system)
Preferable drip irrigation system with app. 0.5 bar working pressure
2. If possible use tank with app. 5 m tower
Optional direct system (set pressure for irrigation at app. 1 bar)
3. Match water use for irrigation with the BRIGHT solar pump capacity
Check for the appropriate pump model
Irrigation area depends on pump parameters [Q / H]
[Q / H] defines the size of the solar generator
4. Control the irrigation system on volume basis (water meter)
Subdivide the fields into equal plots
Calculate drip line length with a +/- 10% variation in water volume
Use bigger filters and distribution pipes to reduce friction losses
5. Use BRIGHT SOLAR power pack for peak (max) water needs in summer
Night time irrigation
25. Installed Pump Sites in Gujarat State
Gujarat State : 5HP 183 Systems
3HP 64 Systems
2HP - 41 Systems
1HP - 29 Systems
7.5HP - 06 Systems
10HP - 02 Systems
Other States : More than 2000
Systems
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