This guide from Orbit Submersible Pumps — a trusted manufacturer of Solar DC Submersible Pumps in India — walks you through every key factor you need to consider before making your purchase decision. From well depth and flow rate to HP selection, solar panel sizing, and subsidy eligibility, this step-by-step guide has everything you need to make the right choice for your specific farm and irrigation requirements.
Step 1: Understand Your Water Source
The first and most important step in choosing a solar water pump is to clearly understand your water source. The type, depth, and characteristics of your water source directly determine which pump model and specifications you need.
Identify Your Water Source Type
- Open Well: An open dug well requires a Vertical Openwell Submersible Pump designed for submerged operation inside a wide-diameter well. Orbit’s Solar DC Submersible Pump sets are ideal for open well applications.
- Borewell: A narrow-diameter borewell requires a slimmer submersible pump designed for tight-bore installations. Confirm the borewell diameter before selecting a pump.
- Canal or Farm Pond: Surface water sources like canals, tanks, or farm ponds require pumps with appropriate suction and delivery configurations.
Measure the Static Water Level and Total Head
The total head — the vertical distance the pump must push water from the source to the delivery point — is critical for pump selection. This includes the depth of the water surface below ground (static water level), the elevation of your fields above the pump, and friction losses in the delivery pipes. Always choose a pump whose maximum head rating comfortably exceeds your calculated total head to ensure reliable performance even when water levels drop during summer months.
Step 2: Calculate Your Farm’s Water Requirement
Every crop has a specific daily water requirement, and every farm has a total irrigation area that determines the total volume of water needed. The pump’s flow rate — measured in cubic metres per hour (m³/h) — must be sufficient to deliver the required water volume to your fields within the available sunshine hours (typically 6 to 8 hours per day).
As a general guide, consider the following factors to estimate your flow rate requirement:
- Total irrigated area (in acres or hectares)
- Crop water demand (litres per day per acre — varies by crop type and season)
- Irrigation method (drip requires lower flow at higher pressure; flood irrigation requires higher flow)
- Daily sunshine hours available (typically 6 to 8 hours across most of India)
Orbit’s technical team can help you calculate your farm’s exact water requirement and recommend the right pump model based on your inputs. Contact them at orbitsubmersiblepump.com/product/solar-dc-submersible-pump/ for a free consultation.
Step 3: Select the Right HP and Flow Rate
Once you know your total head and required flow rate, you can select the appropriate pump HP (horsepower). A higher HP pump delivers more water output and can push water to greater heights, but also requires more solar panels. Selecting a pump with excessively high HP for a small farm results in unnecessary capital expenditure on solar panels, while an undersized pump will fail to meet your irrigation needs.
The table below provides a general HP and flow rate guide based on farm size:
| Farm Size | Recommended HP | Approx. Flow Rate | Suggested Head |
| Up to 1 Acre | 0.5 HP – 1 HP | Up to 10 m³/h | Up to 30 metres |
| 1 – 3 Acres | 1 HP – 2 HP | Up to 20 m³/h | Up to 50 metres |
| 3 – 5 Acres | 2 HP – 3 HP | Up to 30 m³/h | Up to 70 metres |
| 5 – 10 Acres | 3 HP – 5 HP | Up to 40 m³/h | Up to 100 metres |
| 10+ Acres | 5 HP – 10 HP+ | Up to 54 m³/h | Up to 141 metres |
Step 4: Choose Between Single-Phase and Three-Phase
Orbit Solar DC Submersible Pumps are available in both single-phase and three-phase configurations. For smaller farms and lower HP requirements (up to approximately 3 HP), single-phase DC solar pump systems are typically sufficient and easier to install. For larger farms with higher HP requirements, three-phase configurations offer smoother motor operation, greater efficiency at higher loads, and better long-term reliability. Your farm’s power connection type and total pump HP should guide this decision.
Step 5: Size Your Solar Panel Array Correctly
The solar panel array must generate sufficient watt-peak (Wp) capacity to power your pump at full load during peak sunshine hours. A common rule of thumb is to allow approximately 1,200 to 1,500 Wp of solar panel capacity per HP of pump power, though the exact sizing depends on your geographic location, panel efficiency, local irradiance levels, and system losses. Always oversize slightly to account for dust, temperature derating, and seasonal variation in sunlight.
Orbit Solar DC Submersible Pump Sets include MPPT (Maximum Power Point Tracking) solar controllers that optimise power extraction from the panels throughout the day — including during partially cloudy conditions — ensuring your pump operates efficiently across varying sunlight levels.
Step 6: Evaluate Pump Material and Build Quality
The material quality of the pump directly determines its operational lifespan and maintenance requirements. When evaluating pump quality, look for:
- Stainless steel impellers and shafts: Essential for water sources containing sand, silt, or dissolved minerals that can erode cheaper cast iron components.
- Anti-corrosive epoxy coatings: Protect the motor stator and rotor from moisture ingress and chemical corrosion during continuous submerged operation.
- Water-lubricated bearings: Eliminate the need for external lubrication and prevent contamination of the water source.
- IP58 or higher protection rating: Ensures the motor is fully sealed against water ingress during deep submerged operation.
- Brushless DC motor: Delivers higher efficiency, lower heat generation, and a longer lifespan compared to conventional brushed motors.
Orbit Solar DC Submersible Pumps incorporate all of the above, manufactured to ISO 9001-2008, BEE, ISI, and NABCB standards, and fully tested before dispatch to guarantee performance from day one.
Step 7: Check Government Subsidy Eligibility
Before finalising your solar pump purchase, always check your eligibility under the PM-KUSUM (Pradhan Mantri Kisan Urja Suraksha evam Utthaan Mahabhiyan) scheme and your respective state government’s solar irrigation subsidy programme. Under PM-KUSUM, eligible farmers can receive subsidies of up to 60% to 90% of the total solar pump system cost, dramatically reducing the capital investment required. Orbit Solar DC Submersible Pump Sets are designed to meet PM-KUSUM specifications, and the Orbit team can guide you through the subsidy application process.
Solar Pump Selection Checklist at a Glance
Use this quick checklist before making your final solar pump purchase decision:
| Selection Factor | What to Check |
| Water Source Depth | Choose head rating that exceeds your well or source depth |
| Farm Size & Crop Type | Match flow rate (m³/h) to total irrigation area & water demand |
| Power Supply Type | Select single-phase or three-phase based on your grid connection |
| Solar Panel Capacity | Match panel watt-peak to pump HP for full-load operation |
| Pump Material | Stainless steel for water with sand or minerals; cast iron for clean water |
| Controller Type | MPPT controller preferred for low-light & cloudy-day performance |
| Government Subsidy | Confirm PM-KUSUM or state scheme eligibility before purchase |
| Brand Certification | Check for ISI, BEE, ISO certifications for quality assurance |
Why Choose Orbit Solar DC Submersible Pump?
When you have completed your selection process, Orbit Submersible Pumps offers a Solar DC Submersible Pump range that ticks every box:
- Flow range up to 54 m³/h and head up to 141 metres for all farm sizes
- Power range of 0.5 HP to 10 HP+ to match any irrigation scale
- Brushless DC motor with MPPT controller for maximum solar efficiency
- Stainless steel and cast iron components with epoxy anti-corrosion coating
- PM-KUSUM subsidy-compatible specifications
- ISO 9001-2008, BEE, ISI, and NABCB certified manufacturing
- 30+ years of engineering excellence under Vishvakarma Engineering Works
- 100% tested before dispatch — zero compromise on quality
- Expert technical guidance and pan-India dealer support
Explore the complete Orbit Solar DC Submersible Pump range at: orbitsubmersiblepump.com/product/solar-dc-submersible-pump/
Frequently Asked Questions (FAQs)
Q1. How do I know what HP solar pump I need for my farm?
Your required pump HP depends on three key factors: the total head (depth of your water source plus the elevation of your delivery point), the required flow rate (based on your farm size and crop water demand), and the number of available sunshine hours per day. As a general guide, farms up to 1 acre typically need 0.5 HP to 1 HP, while farms of 5 acres or more may require 3 HP to 5 HP or higher. Orbit’s technical team can provide precise recommendations based on your specific farm parameters.
Q2. What is the difference between MPPT and PWM solar controllers?
MPPT (Maximum Power Point Tracking) controllers are more efficient than PWM (Pulse Width Modulation) controllers because they continuously optimise the power output of the solar panels to match the pump’s requirements — especially under varying sunlight conditions such as partial cloud cover or early morning and late evening light. Orbit Solar DC Submersible Pumps use MPPT controllers, ensuring higher water output across the full day, not just during peak sunshine hours.
Q3. Can I use an Orbit Solar DC Pump for both open wells and borewells?
Orbit manufactures solar-powered submersible pumps for both open well and borewell applications. The correct model depends on the diameter of your well or borewell and the required head and flow specifications. Contact Orbit’s technical team with your well details to identify the best-matched pump model for your specific water source.
Q4. How many solar panels do I need for a 2 HP solar pump?
For a 2 HP solar pump, you will typically need approximately 6 to 8 solar panels of 250 Wp to 325 Wp each, giving a total panel capacity of around 1,500 to 2,600 Wp. The exact number depends on your location’s solar irradiance, the efficiency of the panels, and system losses due to wiring, dust, and temperature. Orbit’s team provides complete solar system sizing as part of their product consultation.
Q5. Is it better to buy a solar pump set or source the pump and panels separately?
Purchasing a complete solar pump set — pump, motor, MPPT controller, and recommended panel specifications together — is generally the better option. It ensures all components are matched for optimal performance and compatibility, simplifies installation, and is typically required for PM-KUSUM subsidy applications. Orbit offers complete Solar DC Submersible Pump Sets designed and tested as integrated systems for maximum reliability.
Q6. What maintenance does a solar water pump require?
Solar DC Submersible Pumps require minimal maintenance compared to diesel engine pumps. Key maintenance tasks include periodic cleaning of solar panels to remove dust and bird droppings (which can reduce output by 10% to 25%), annual inspection of pipe connections and delivery systems, and occasional pump inspection for sediment build-up. Orbit’s brushless DC motors and water-lubricated bearings eliminate the need for oil changes or mechanical lubrication servicing.
Q7. How can I apply for the PM-KUSUM solar pump subsidy for an Orbit pump?
To apply for the PM-KUSUM subsidy, farmers typically need to register with their state’s nodal agency (such as RREC, MNRE state offices, or state electricity boards), obtain pre-approval, and then purchase a pump from an empanelled supplier. Orbit Solar DC Submersible Pump Sets meet PM-KUSUM technical specifications. Contact Orbit’s team for guidance on the subsidy application process and empanelment status in your state.
Conclusion
Choosing the right solar water pump for your farm is a decision that will impact your irrigation efficiency, operational costs, and crop yields for years to come. By carefully assessing your water source depth, farm size, crop water requirements, HP needs, solar panel sizing, and subsidy eligibility, you can make a confident and well-informed investment that delivers real returns season after season.
Orbit Submersible Pumps makes that choice easy with a comprehensive Solar DC Submersible Pump range, expert technical guidance, PM-KUSUM-compatible products, and 30+ years of trusted engineering behind every pump set. Contact Orbit today at orbitsubmersiblepump.com/product/solar-dc-submersible-pump/ and let their team help you find the perfect solar pump for your farm.