Across Punjab and Sindh, solar tubewells have spread quickly. The logic is simple: crops need water in the day, and the sun shines in the day. No diesel to buy, no waiting for the grid.
- Solar pumps run in daytime, which matches irrigation well.
- Motor HP, water depth and daily water need decide system size.
- Most farm pumps use a solar pump drive (VFD), not a home inverter.
- Plan for more panel power than the motor rating, often around 1.3x or more.
How a solar pump system works
Panels feed a solar pump drive, usually called a VFD (variable frequency drive) or solar pump inverter. The drive runs the motor faster when sunlight is strong and slower when it’s weak. There’s normally no battery. The water itself becomes your storage, in a pond or tank.
Pump drive vs hybrid home inverter
For a dedicated tubewell, a solar pump drive matched to the motor is usually the right tool. A home hybrid inverter isn’t designed for large three-phase motors running all day. If you also want to power a farmhouse, it’s common to have a separate small hybrid system for the house.
Sizing basics
Three things decide the size:
- Motor size in HP or kW (1 HP is about 0.75kW).
- Water depth and total head, how far the water must be lifted.
- Daily water need for your crop and acreage.
A common rule is to install panel capacity well above the motor rating, often 1.3 to 1.5 times, so the pump can run at useful speed for more hours, including mornings, evenings and hazy days. A 10 HP motor (about 7.5kW) might get around 10 to 11kW of panels as a starting point.
What to check before paying
- Is the drive rated for your motor’s HP and phase?
- Does it have dry-run protection, so the motor stops if water runs out?
- Is the structure strong enough for open fields with high winds?
- Is there proper earthing? Fields are exposed to lightning.
- Who services the drive when it fails during sowing season?
Security matters
Panel theft is a real concern on remote farms. Anti-theft bolts, a boundary and a watchman’s quarter near the array are worth planning from the start.
Farmhouse power
For lights, fans and a fridge at the farmhouse, a small hybrid inverter with a lithium battery works well. Our small inverter guide covers 1.2kW to 3kW options, and the load calculator will give you a size in minutes.
Farm or tubewell project?
Send us the motor HP, water depth and location. We’ll guide you on the right setup.