A solar well pump kit puts a DC pump in your well and runs it straight off solar panels. It pumps while the sun is up and fills a storage tank, and the tank covers nights and cloudy days. That's why the right kit depends on just two numbers: how many gallons a day you need and how high the pump has to lift the water.
This guide walks through both, then compares five kits using the flow charts their makers publish. Prices were checked on each seller's site on November 3, 2026.
Step 1: How many gallons a day?
Add up everything the well has to supply:
- People. The USGS says each person uses about 80 to 100 gallons a day for indoor home use. A family of four is about 320 to 400 gallons a day.
- Animals and garden. Add these from your own records or your county extension office. They can easily be bigger than the house.
- Your target. Most people size for the busiest days of summer, when gardens and animals drink the most.
Step 2: How much lift? (total dynamic head)
Pump makers rate flow at a given head, in feet. Head is the total height the pump has to push water, plus losses. It's not the same as the depth of your well.
- Water level, not well depth. Measure from the water level while the pump is running (the pumping level) up to the top of the well. A 300-foot well with water at 120 feet starts at about 120 feet of lift.
- Add the rise to the tank. If the tank inlet sits 15 feet above the wellhead, add 15 feet.
- Add pressure if you pump straight into a pressure tank. Each 1 psi equals about 2.31 feet of head, so 40 psi adds about 92 feet. Pumping into an open storage tank avoids this.
- Add pipe friction. Long or narrow pipe adds head. Use your pipe maker's friction-loss chart for your flow and pipe size.
The total is your total dynamic head. Bring that number to every flow chart below.
Step 3: Turn gallons a day into gallons a minute
Solar pumps only run while there's good sun. RPS rates its kits on a 6-hour solar pumping day, so its gallons-per-day numbers are gallons per minute × 60 × 6. To check any pump the same way:
Gallons per day ≈ GPM at your head × 60 × hours of good sun
For 400 gallons a day on a 6-hour pumping day, you need about 1.1 GPM at your head. Your real pumping hours depend on season and location. Our off-grid solar calculator lists average sun hours for every state.
Five kits compared
| Kit | Price (Nov 3, 2026) | What's in the box | Max lift | Flow the maker lists |
|---|---|---|---|---|
| ECO-WORTHY 200W Solar Well Pump Kit | $399.98 | 12 V diaphragm pump, 2 × 100 W panels, 20 A PWM controller, cables | 230 ft | 3.2 GPM max (no flow-at-depth chart on the listing) |
| ROCKSOLAR 0.8 HP Kit A | $1,199.99 | 3" brushless pump with built-in controller, 2 × 445 W panels, combiner box | 289 ft | 10.57 GPM at 131 ft, 8.45 at 164 ft, 4.75 at 230 ft |
| RPS 200 | $1,899.99 | Helical rotor pump, 2 × 100 W panels, controller, well and tank sensors | Rated to 125 ft | 3.1 GPM at 100 ft, 2.1 at 125 ft |
| RPS 400 | $1,994.99 | Helical rotor pump, 4 × 100 W panels, controller, well and tank sensors | Rated to 225 ft | 4.8 GPM at 150 ft, 3.4 at 200 ft, 2.9 at 225 ft |
| RPS 2-inch narrow kits | From $2,089.99 (200N); 400N $2,298.99; 800N $2,735.99 | 2.01" pump for 2.5" and 3" casings, panels, controller, sensors | 800N rated to 325 ft | 400N: 4.5 GPM at 150 ft. 800N: 7.8 GPM at 150 ft, 3.1 at 300 ft |
Specs and prices come from each linked product page. Sellers change prices often, and RPS lists most kits as on sale, so check before you buy. Panel mounts aren't included in the RPS kits above.
Flow at depth, side by side
Here's what each maker lists at the depths most homesteads deal with. Blank means the maker doesn't rate that pump at that head.
| Head | RPS 200 (GPM) | RPS 400 (GPM) | RPS 400N (GPM) | RPS 800N (GPM) |
|---|---|---|---|---|
| 50 ft | 4.4 | 6.9 | ||
| 100 ft | 3.1 | 5.5 | 6.0 | |
| 125 ft | 2.1 | 5.1 | 5.2 | |
| 150 ft | 4.8 | 4.5 | 7.8 | |
| 175 ft | 4.3 | 3.7 | 7.7 | |
| 200 ft | 3.4 | 2.8 | 7.0 | |
| 225 ft | 2.9 | 1.5 | 6.0 | |
| 250 ft | 5.0 | |||
| 300 ft | 3.1 |
ROCKSOLAR lists its 3-inch pump's curve at different steps: 12.42 GPM at 98 ft, 10.57 at 131 ft, 8.45 at 164 ft, 6.60 at 197 ft, 4.75 at 230 ft and 2.64 at 262 ft. RPS publishes its numbers as gallons per day on a 6-hour pumping day. ROCKSOLAR lists gallons per minute only.
Which kit fits which well
- Shallow well, small needs (garden, a few animals, a cabin): the ECO-WORTHY kit is the cheapest way in. It's a 12-volt diaphragm pump, and the listing says to avoid running it more than 4 hours straight so the motor can cool. The listing doesn't give flow at depth, so expect less than 3.2 GPM as lift rises.
- Water level under about 125 feet, household use: the RPS 200 delivers 3.1 GPM at 100 feet, which is about 1,116 gallons on RPS's 6-hour day. That covers the USGS figure for a family of four with room to spare.
- Water level 125 to 225 feet: the RPS 400 still lists 4.8 GPM at 150 feet (1,728 gallons a day by RPS's numbers).
- Narrow or old windmill casings (2.5" or 3"): the RPS 2-inch kits are built for these. The 800N is the only kit here rated past 300 feet.
- Big flow, moderate depth (livestock, irrigation): ROCKSOLAR's Kit A lists the highest flow in this group down to about 165 feet (8.45 GPM at 164 ft), from a bigger 890-watt array. Past about 200 feet, the RPS 800N lists more.
Battery backup or a tank?
The kits above are built to pump straight from the panels into a storage tank during the day. RPS kits include a tank shut-off sensor for this. RPS and ROCKSOLAR both say their pumps can run from batteries or a generator when you need water at night or through long cloudy spells. If you want that, size the battery with our off-grid solar calculator and add the pump's watts and running hours.
Before you buy
- Get your pumping water level from your well log or a well driller, not a guess.
- Check the pump fits your casing size.
- Ask the seller to confirm the model at your total dynamic head. RPS offers free sizing by phone, and its listing says that's backed by a money-back water guarantee after proper installation.
- Plan the panel mount, wire run and a dry spot for the controller.
- Pull and set the pump safely. Consider hiring a pump installer for this step.
Sources
- USGS Water Science School: How much water do I use at home each day?
- RPS Solar Pumps product pages: RPS 200, RPS 400, RPS 2-inch kits, all kits (checked November 3, 2026)
- ROCKSOLAR: 0.8 HP Solar Submersible Pump + Solar Panel Kit (checked November 3, 2026)
- Amazon: ECO-WORTHY 200W Solar Well Pump Kit (checked November 3, 2026)