How many solar panels are needed to run a deep well pump?

For standard 100 to 200 ft pumping lift delivering 3 to 5 GPM, a 24V or 36V DC brushless pump requires 400W to 800W of solar panels. For wells over 300 ft, a 48V DC pump requires a 1,000W to 1,600W array.

What is Total Dynamic Head (TDH)?

Total Dynamic Head is static lift (water level depth) plus surface elevation rise plus friction pipe head loss caused by fluid flow.

Solar Submersible Well Pump & PV Array Sizing Calculator

1. Enter Well & System Specs

Pumping Water Level (ft): Static water level plus seasonal drawdown depth inside well casing.

Surface Elevation Rise (ft): Vertical rise from wellhead to storage cistern inlet.

Target Flow Rate (GPM): Required gallons per minute to meet daily usage.

Total Pipe Run Length (ft): Total drop pipe inside casing plus surface piping run.

Pipe Inner Diameter & Type:

2. Engineered System Requirements

Total Dynamic Head (TDH):

0.0 ft

Total physical lift combined with fluid friction backpressure[cite: 5].

Minimum Solar PV Array Size:

Recommended panel array capacity accounting for motor efficiency & 1.25× derate factor[cite: 5].

Recommended DC Voltage Framework:

Enter specs to calculate

Friction Head Loss (Hazen-Williams):

0.0 ft

Well Pumping Depth vs. Solar Array Sizing Reference

Standard DC submersible pump voltages, required PV array wattages, and delivery rates based on Total Dynamic Head (TDH):

Head Depth (TDH)	Flow Rate (GPM)	DC Motor Framework	Min Solar Array	Daily Yield (5 Sun Hrs)	Drop Pipe Spec
50 – 100 Feet	6.0 – 8.0 GPM	12V / 24V DC Brushless	300W – 400W Array	1,800 – 2,400 Gal	1.0" or 1.25" PE
100 – 180 Feet	4.0 – 5.5 GPM	24V DC Framework	500W – 600W Array	1,200 – 1,650 Gal	1.0" PE
180 – 280 Feet	3.0 – 4.5 GPM	36V DC High-Lift	700W – 900W Array	900 – 1,350 Gal	1.0" or 1.25" PE
280 – 400 Feet	2.5 – 3.8 GPM	48V Industrial Brushless	1,000W – 1,400W Array	750 – 1,140 Gal	1.25" Sch 80
400+ Feet	1.8 – 2.8 GPM	72V / 110V MPPT High-Pressure	1,500W – 2,000W Array	540 – 840 Gal	1.25" Stainless / Sch 80

Frequently Asked Questions

Can I run a solar well pump directly from panels without batteries?

Yes. Integrated MPPT controllers adjust pump speed based on sunlight, filling tanks directly without batteries.

Why is a 1.25x derating factor applied to solar arrays for pumps?

Solar panels lose output on hot days and during dust accumulation. A 25% buffer ensures pump displacement remains consistent through early morning and late afternoon sun.

Verified Off-Grid Solar Pumping Kits & Gear

Submersible Solar Well Pump Kit

Complete multi-stage high-lift DC brushless pump systems with integrated MPPT control boxes[cite: 5].

View Matching Pump Kits

Monocrystalline Solar Panels

Heavy-duty solar panel kits matching minimum wattage footprint to power your deep well circuit[cite: 5].

Browse Matching Solar Panels

Float Switch & Cistern Valves

Automate your storage cistern filling sequence to prevent tank overflow and dry-run pump damage[cite: 5].

Shop Float Switches

Affiliate Disclosure: As an Amazon Associate, this platform earns commissions on qualifying off-grid equipment hardware purchases completed through our automated marketplace links at zero extra cost to you[cite: 5].

Engineering Disclaimer: Calculations generated by this software tool are mechanical design estimates based on standard fluid dynamics models and friction loss parameters[cite: 5]. Underground well characteristics, pump performance data curves, and local solar insolation values vary by location[cite: 5]. Always consult original equipment manufacturer documentation or a professional well driller before installation[cite: 5].