What a solar pump setup does and what you need before you start

A solar pump uses panels to power a submersible or surface pump that pulls water from your well. Unlike a grid-powered pump, it runs during daylight hours without electricity bills or a connection to the power line. The system has three main parts: solar panels that collect sunlight, a controller that manages power flow, and the pump itself.

Before you begin, confirm your well depth and the gallons per minute (GPM) you need. A well driller's report or your current pump documentation will have this information. You will also need to know whether your well currently has a pump installed—if it does, you may be able to replace just the pump and reuse some existing plumbing. If your well is dry or abandoned, you will need to verify it can still produce water before investing in a new system.

Check local codes and permitting rules. Some counties require a licensed well contractor to install or modify a pump system, while others allow homeowners to do the work themselves. Call your county health department or building department to ask what applies to your property.

Key Takeaways

  • Solar pump systems need three components—panels, a controller, and a pump—sized to match your well depth and water output needs.
  • You must know your well's depth and current flow rate before selecting equipment, information usually found in well drilling records or from your current pump specs.
  • Local codes vary widely on whether homeowners can install a pump themselves or must hire a licensed contractor; contact your county health or building department first.
  • The pump connects to existing well casing or a new drop pipe, the controller sits above ground near the panels, and panels mount on a roof or pole where they receive full sun.
  • Priming the pump and testing water flow before final connection prevents damage and confirms the system works before you rely on it.

Sizing the solar panels and controller for your well depth

Solar pump power requirements depend on how deep your well is and how much water you need per day. A shallow well (under 50 feet) with modest water use may need only 100 to 200 watts of solar panels, while a deep well (200+ feet) can require 400 watts or more. The deeper the pump must push water, the more power it consumes.

Use the pump manufacturer's power chart, which lists watts needed at different depths. If you are replacing an existing pump, the old pump's nameplate will show its power draw—a solar system must provide at least that much. If you are starting fresh, a solar pump supplier can calculate your needs based on well depth, desired flow rate, and your location's average sunlight hours.

The controller (also called a charge controller or inverter) regulates power from the panels to the pump. It prevents overcharging, protects against voltage spikes, and allows the pump to run even on cloudy days if you add a battery. For a basic system without storage, choose a controller rated for at least 125 percent of your panel output. A 200-watt panel system needs a controller rated for 250 watts or higher.

Selecting and preparing the pump for your well

Solar-powered pumps come in two types: submersible pumps sit inside the well casing and push water up, and surface pumps sit above ground and pull water up through a drop pipe. Submersible pumps work better for deep wells and are more efficient, but they are harder to service. Surface pumps are easier to maintain but can only lift water about 25 feet, so they suit shallow wells.

Match the pump's voltage to your solar panel system. Most small solar systems run 12 or 24 volts DC (direct current), while larger systems use 48 volts or 120 volts AC (alternating current). The pump, panels, and controller must all be rated for the same voltage, or the system will not work.

Before installation, inspect the pump for damage and check that all fittings and seals are intact. If the pump has been in storage, run it briefly on a test power source to confirm it spins freely. Do not install a pump that makes grinding noises or leaks—return it and get a replacement.

Running the drop pipe and electrical lines into the well

If you are installing a submersible pump, you need a drop pipe (also called a riser pipe) that carries water from the pump to the surface. This is usually PVC or galvanized steel pipe sized to fit inside your well casing. Measure the well depth and add 5 to 10 feet to account for the pump sitting above the bottom and the pipe extending above ground.

Attach the pump to the drop pipe using the pump's threaded outlet fitting. Wrap the connection with plumber's tape to prevent leaks. find the pump and pipe together with stainless steel hose clamps every 10 feet so they do not separate as you lower them into the well.

Run the electrical cable alongside the drop pipe, securing it with additional clamps every 5 feet. Use cable rated for submersible pump use (usually UV-resistant and waterproof). Never use regular household electrical wire—it will fail underground. Leave 10 to 15 feet of cable coiled above ground so you can connect it to the controller without strain.

Lower the pump and pipe slowly into the well using a rope or pulley system. Do not drop it or let it fall, as this can damage the pump seal. Stop when the pump rests on the well bottom or on a sediment screen if one is installed. The drop pipe should extend 2 to 3 feet above the well casing so you can connect it to your pressure tank or distribution line.

Mounting the solar panels and positioning the controller

Solar panels must face the sun and receive at least 5 to 6 hours of direct sunlight daily to power a pump reliably. Mount them on a south-facing roof (in the Northern Hemisphere) or on a ground pole where trees and buildings do not cast shadows. Panels angled at your latitude plus 15 degrees will capture the most winter sun; a fixed angle of 30 to 45 degrees works well for most locations.

Use a roof-mounted racking system if your roof is strong enough, or install a ground pole mount if roof mounting is not possible. find all bolts and connections with stainless steel hardware to resist rust. Leave at least 2 feet of clearance around the panels for air circulation, which keeps them cooler and more efficient.

Place the controller in a weatherproof enclosure near the well, away from direct sun and rain. Mount it on a post or wall at least 3 feet above ground so it stays dry during heavy rain or snow. Run the cable from the panels down to the controller in a conduit or cable tray to protect it from damage and UV exposure.

Connecting the controller, pump, and panels in the right order

Electrical connections must follow a specific sequence to avoid damaging the controller or pump. First, connect the solar panels to the controller's input terminals, matching positive to positive and negative to negative. Use appropriately sized wire—a 200-watt panel system typically needs 10-gauge wire, while larger systems need 6-gauge or thicker. Undersized wire will overheat and create a fire hazard.

Next, connect the pump cable to the controller's output terminals. Again, match positive to negative correctly. If the pump does not run after you power it on, reverse the pump connections—some controllers are sensitive to polarity.

Do not connect the battery (if you have one) until the panels and pump are in place and tested. Batteries add complexity and cost but allow the pump to run on cloudy days or at night if you store water in a tank.

Before you seal any connections, test the system in daylight. The pump should start within a few seconds of sunlight hitting the panels. If nothing happens, check that all wire connections are tight and that the controller display shows power input from the panels. A loose connection is the most common reason a new system does not start.

Priming the pump and testing water flow

A submersible pump does not need priming because it is already submerged. A surface pump, however, must be filled with water before it can lift water from the well. Fill the pump housing and the drop pipe with water using a garden hose, then close the fill valve. The pump will now be able to draw water up from below.

Once the system is connected, run it for 10 to 15 minutes in full sunlight and observe the water output. The flow should be steady and clear. If water is brown or cloudy, the well is stirring up sediment—run the pump for another 30 minutes to flush it out. If flow is weak or stops after a few minutes, the pump may not be sized correctly for your well depth, or the controller may be limiting power.

Check all pipe connections and fittings for leaks. Tighten any connection that drips. If a fitting leaks after tightening, turn off the pump, drain the line, and reconnect it with fresh plumber's tape.

Once water flows clearly and steadily, connect the pump outlet to your pressure tank, storage tank, or distribution line. Install a check valve between the pump and tank to prevent water from flowing backward into the well when the pump stops. This protects the pump and keeps your tank full.

Frequently Asked Questions

Can I use my existing well pump with solar panels?

Only if your current pump is DC-powered or if you add an inverter to convert solar DC power to AC power. Most grid-powered pumps run on 120 or 240 volts AC and cannot run directly on solar panels. A solar-specific pump is more efficient and cheaper than adding an inverter to an old pump.

What happens to the pump on cloudy days or at night?

Without a battery, the pump stops when sunlight is too weak. If you need water at night or during storms, you must add a battery bank to store power. Batteries add $1,000 to $3,000 to the system cost but let you pump water anytime. Many homeowners use a storage tank instead—the pump fills the tank during sunny days, and you draw from the tank as needed.

How deep can a solar pump pull water?

Submersible pumps can reach 300 feet or deeper, but power requirements increase sharply below 100 feet. A 300-foot well may need 500+ watts of panels, making the system expensive. Surface pumps are limited to about 25 feet. Check with a solar pump supplier to confirm what depth your budget can support.

Do I need a permit to install a solar pump?

Requirements vary by county. Some allow homeowners to install a pump without a permit, while others require a licensed well contractor. A few counties require inspection after installation. Call your county health department or building department to learn what applies to your property before you start work.

What maintenance does a solar pump system need?

Check panel connections and wiring twice a year for corrosion or loose bolts. Clean panels if dust or pollen builds up—use a soft brush and water, never abrasive cleaners. Inspect the drop pipe and pump cable for damage. Submersible pumps typically last 10 to 15 years before the seal fails and the pump must be replaced.