1. Farming Off‑Grid: Building a Solar‑Powered Irrigation System

Farming Off‑Grid: Building a Solar‑Powered Irrigation System

 

 

Farming Off‑Grid: Building a Solar‑Powered Irrigation System

By Teagan Moran, OSU Extension Service and Scott Duckett, The Farm Up Lost Creek

Published: May, 2026

When Scott Duckett returned to his family’s 22‑acre property near Lost Creek in 2020, he wasn’t just coming home, he was stepping into a long‑imagined dream of building a farm from the ground up. The land had been in his family for more than 70 years, used mostly for pasture and hay. Scott and his wife Katherine arrived with a clear vision: plant perennial food crops that could feed people and restore the land.

The property sits in a small foothill valley 25 minutes outside Eugene, at the gateway to the Middle Fork River and the Cascades. It produced hay in the 1970s and early 1980s and supported cattle and horses, but intensive agriculture hadn’t occurred there for decades. “To my knowledge, the soils have never been sprayed,” Scott said.  Still, the farm faced a major hurdle: it had no agricultural infrastructure. No irrigation system. No power. No water rights. And no straightforward path to securing any of those things.

“It was a rectangular piece of land with no infrastructure other than fencing,” Scott explained. “Running electricity to the property was going to be incredibly expensive. Water storage wasn’t feasible. And I didn’t live on the farm full‑time, so I needed a system that could run without me being there every day.” That challenge set him on a multi‑year journey to design an off‑grid, solar‑powered watering system capable of supporting hazelnuts, berries, grapes, walnuts, and a growing fruit orchard — all without traditional utilities.

 

Starting From Scratch: Soil, Fencing, and the First Crops

Scott began the way many new farmers do: by learning everything he could. He enrolled in OSU Extension’s classes, including agritourism and soils courses. “The soil class really informed my decision‑making around the farm,” he said. “It helped me understand where to plant different crops.” Beyond classes, he relied heavily on Extension’s online resources to plan his crops and planting methods, and he reached out to Extension staff who connected him with on‑campus experts when he had specific crop questions. “The Extension program and staff were instrumental in providing me technical and moral support throughout my first several years,” he said.

He started small with a quarter‑acre strawberry patch watered from the domestic well at the nearby house. But he quickly realized that relying on residential water for commercial crops wasn’t sustainable or legally appropriate long‑term. “My water plan kept going back and forth between planning for not having water and planning if I had water,” he said. Meanwhile, he continued planting hazelnuts, berries, grapes, and a diverse orchard — all crops that could survive without irrigation but would establish better with it. By 2024, he had added a small walnut orchard and plots for grains and beans.

 

The Water Rights Roller Coaster

Knowing irrigation would eventually be necessary, Scott applied for a temporary water right to establish his perennial crops, and it was approved. He later submitted an application for a permanent right which was well received. During that period, statewide interpretation of groundwater data shifted, and his previously promising application was denied. It was a discouraging setback, but after an appeal process and further review, the state determined that his application met the updated criteria. His permanent water right is now moving through final paperwork which is a critical step in securing the farm’s long‑term future. 

Designing an Off‑Grid Solar Watering System

Even with water rights secured, Scott still had no electricity on the farm, and the cost of bringing power to the property remained prohibitive. That pushed him toward a creative solution: a fully off‑grid, solar‑powered irrigation system.

The system typically operates from June through September, and sometimes into October depending on weather. Because it was designed to establish permanent orchard crops, irrigation is applied 2–3 days per week for one to two hours per day. This delivers approximately 1–2 gallons per plant per watering session through slow drip emitters, encouraging deep root growth and allowing trees and bushes to eventually be weaned off irrigation after establishment.

In practice, the large orchard is irrigated in two zones, each covering roughly three fenced acres. Emitters are spaced 4 feet apart for berry bushes and 12 feet apart for tree rows. With two hours of flow, each zone receives about 5,000 gallons per watering session.

To help other growers visualize the layout and scale of the project, Scott created a site map showing the well, solar arrays, holding tanks, irrigation stations, and crop zones. The map illustrates how the system moves water across the property using only solar power and gravity.

If you walked the system in order, you’d start at the first bank of 8 solar panels and control panel, move to the well pump about 30’ away which brings water from 110’ underground to an 1,100 gallon tank about 30’ uphill of the well. 

From this holding tank, the water flows downhill in flexible above ground lines approximately 800’ to two different orchards each with their own 2,500 or 1,100 gallon holding tank.  At each irrigation area, there is a station with solar panels, a battery bank which is charged by the panels (used to provide constant steady electricity to the pressure pump), a “smart” variable speed pressure pump pushing the water out, and finally the drip lines delivering it to each crop zone and plant. 

 

Getting water from the well to Irrigation Stations:

Sun → Solar Panels (8) → Well Pump → Holding Tank→Water Lines→Pumping Tank 

 

Getting water from the Irrigation Stations to the Crops: 

Sun —> Solar panels→ Battery Bank→Pressure Pump → Drip Lines → Crops

Below is a breakdown of each component and why it matters.

1. Solar Array — the Power Plant

Scott installed a ground‑mounted solar array sized to run:

  • a submersible well pump
  • a pressure pump
  • the irrigation controller
  • battery storage

The array is the system’s “engine.” Its size determines how many hours of irrigation you can run during peak summer heat. 

During peak summer weather, the well pump operates whenever direct sunlight hits the panels—from early morning until roughly one hour before sunset. Water is pumped continuously throughout the day to fill irrigation tanks ahead of scheduled watering cycles. When irrigation begins, the tanks are already sufficiently full, and the well continues supplying water while the pressure pump runs. On hot, sunny days, the pressure pump typically operates 4–5 hours. 

Why it matters: A properly sized array ensures the well pump can run continuously through long summer days—keeping tanks full and maintaining reliable irrigation even during the hottest, driest periods.

 

2. Battery Bank — the Energy Pantry

Because irrigation often runs early or late in the day, Scott added deep‑cycle batteries to store excess solar energy and provide a constant voltage for the pump.

Why it matters:  Batteries allow irrigation to run even when the sun isn’t shining — essential for off‑grid reliability.

Prolonged wildfire smoke reduces the number of hours the well can pump because early‑morning and late‑evening solar input is diminished. However, the battery bank provides enough stored energy for the pressure pumps to meet irrigation demand even during extended smoke events.

 

3. Submersible Well Pump — the water lifter

A DC‑powered submersible pump slowly fills the system throughout the day.

Designed for:

  • low‑flow, steady pumping
  • high efficiency
  • solar compatibility

Why it matters:  Slow, steady pumping uses far less energy than high‑flow systems and pairs beautifully with solar and drip systems.

 

4. Holding Tank — the water savings account

Instead of pumping directly into irrigation lines, Scott uses a large 1,100 or 2,500 gallon tank that:

  • stores water
  • maintains consistent pressure
  • reduces pump cycling

Why it matters:  Think of this as a water “buffer.” It smooths out pressure and ensures a steady flow into the variable speed pressure pump.  

Water travels from the well to holding tanks at three irrigation stations through a 1¼‑inch polypropylene main line. The furthest tank is approximately 1,200 feet from the well, with water moving via a combination of gravity and well‑pump pressure. From each tank, the variable‑speed pressure pump pushes water through header lines and smaller irrigation tubing. In the large orchard, each zone contains roughly 5,000 feet—just under one mile—of irrigation tubing. Pressure variations within zones are usually caused by small leaks or damaged emitters. Elevation changes can affect pressure if leaks are present, but properly installed systems perform well even on semi‑steep slopes.

 
5. Pressure Pump — the clean‑water push to crops

A new style “variable speed” pressure pump draws from the holding tank and pushes water into the irrigation lines. 

Scott added:

  • sediment filtration
  • pressure regulation
  • zone valves

Gravity is used only to move water from the well to the holding tanks once it reaches the surface. All irrigation from the tanks requires the pressure pump to pressurize the lines; gravity alone is not used for crop irrigation. 

Why it matters:  Clean, consistent pressure keeps drip systems functioning and prevents clogging, especially important in off‑grid setups where every repair costs time and energy.

 

6. Drip Irrigation Network — the delivery system

The irrigation system is divided into zones for:

  • hazelnuts
  • berries
  • grapes
  • fruit trees

Each zone uses drip lines or micro‑emitters matched to crop needs.

Scott worked with technical experts to size tubing, tanks, and pumps based on crop needs, well capacity, and elevation changes. Flow rates were calculated using technical charts provided by Fisher’s Supply in Canby. He selected 1‑gallon‑per‑hour emitters for trees and berry bushes to simplify weekly water calculations. These emitters require a minimum of 9 psi to function properly, while the variable‑speed pressure pump delivers 35–40 psi across the system to ensure consistent flow.

The well pump is a DC‑powered solar pump (with an AC option), while the variable‑speed pressure pump requires steady AC power from the battery bank. Pump size was matched to the natural flow capacity of the well with support from RPS Solar Pumps engineers, which in turn determined the number of solar panels needed—eight in total.

Why it matters:  Drip irrigation uses low pressure and low flow — perfect for solar‑powered systems. It also conserves water and reduces weed pressure.

Practical Lessons Learned From Running an Off‑Grid System

Scott’s experience offers invaluable insights for other growers considering off‑grid irrigation. These lessons come directly from troubleshooting, repairing, and refining the system over several seasons.

1. Build a dedicated irrigation toolbox

Scott keeps a tote stocked with:

  • crescent wrench
  • flat screwdriver
  • extra rings and clamps
  • emitters
  • repair fittings
  • a cordless drill with the correct socket

“It makes a huge difference,” he said.

 

2. Walk the lines — don’t just turn the system on

Leaks and inefficiencies often aren’t visible from a distance. Walking the lines while the system is running is essential.

 

3. Size the system appropriately

An oversized pump will drain solar batteries quickly. “A smaller, efficient system may outperform a powerful one that exhausts energy in a few hours,” Scott noted.

 

4. Use compatible materials

Stick with polypropylene drip fittings. Mixing PVC, older fittings, or incompatible plastics leads to failures.

 

5. Find a reliable local supplier

Online parts are convenient, but a local supplier can help troubleshoot, replace broken components, and ensure compatibility.

 

6. Monitor heat‑related expansion

Temperature swings cause tubing to expand and contract dramatically.

“A 100‑foot drip line may stretch to 110 feet in the afternoon and shrink overnight,” Scott said. Emitters must be placed with this movement in mind.

 

7. Secure tubing — but allow for movement

Landscape staples help prevent lateral movement, but tubing still needs room to expand lengthwise.

 

8. Choose drip tape or rigid tubing based on crop

For clean, sprayed rows (e.g., broccoli), drip tape may be ideal. For perennial or mixed plantings, rigid tubing performs better.

 

As of this writing, the entire system is still operating with its original pumps, batteries, solar panels, and control boxes. The biggest unknown is the lifespan of the deep‑cycle batteries, which experience both heat and cold but continue to perform well.

Most maintenance costs come from wildlife damage—coyotes chewing poly tubing, a bear tearing out the well’s electrical line—and occasional mower strikes. Summer heat expansion can also cause fittings to separate, requiring quick repairs. Early PVC components were removed because they were prone to freeze damage. Currently, no filters are used in the system.

The lifespan of major components varies widely depending on exposure and use. Most equipment remains outdoors year‑round, except for the variable‑speed pressure pumps, which are removed and stored indoors during winter.

Access to grid power would eliminate the need for solar panels and batteries, but running electricity to a field site can still be costly. For farms with existing grid access, the system would function like a standard drip irrigation setup powered by the utility grid.

This design can also be scaled down economically. A smaller version of the system could reliably irrigate 1–2 acres for several hours per day.

 

A Farm Built on Ingenuity and Resilience

Today, four and a half years into the project, Scott’s farm, The Farm Up Lost Creek,  is home to hazelnuts, berries, grapes, walnuts, and fruit orchards. The off‑grid solar watering system keeps young trees alive through hot summers, and the permanent water right will soon secure the farm’s long‑term future.

 

Project Budget Summary:

The Farm Up Lost Creek Irrigation System Costs - 6 Acre Fruit Orchard and 2 Acre Nut orchard 

Costs listed here reflect Scott’s expenses at the time of installation. Prices for pumps, tanks, solar components, and irrigation supplies vary widely by year and supplier. This budget is provided solely as an example to help growers understand the general scale of investment. Mention of specific products or companies does not imply endorsement by OSU Extension. 

The system was built in phases over several years, with careful attention to cost, efficiency, and long‑term maintenance. Scott tracked expenses for each major component and is sharing that to help other growers understand the financial considerations of building a similar system.