Solar Energy Is Powering Irrigation

“It was a no-brainer.” That was the conclusion Rick Elnicki came to when he considered installing solar panels to power a new irrigation system on a 113-acre field in southeast Kansas earlier this year. He had already decided to install a NutraDrip drip irrigation system under the plot to encompass more acres than a pivot could cover. Plus, he figured drip would be more efficient, since the water drawn from a 23-acre pond is delivered directly to the root zone.

The main reason Elnicki went with solar power was the cost savings, he related. “It was going to cost around $100,000 to run three-phase power from the highway to the field. That was about the same as what the solar system and installation were going to cost. Plus, I would still have an electric bill for every month that I use the drip system.”

Elnicki said his decision was further swayed by a USDA Rural Energy for America Program (REAP) that paid half the cost of the solar system. Although some states and/or utilities also allow users to trade excess solar energy for credit or payment, Elnicki said that isn’t the case in his situation, since the system isn’t connected to the grid. To compensate, he installed a 70 kW solar system — nearly twice as much solar capacity as needed to power his 20-horsepower pump— and purchased enough lithium battery power to run the drip system all night if necessary.

“I figure if it is cloudy or the sun is just coming up or going down, I’ll have less electrical generation than normal, so, this way, I know there’s always power available,” he added.

Elnicki said he is also using the installation as a test, since the irrigated portion covers only about half of the field. “I’ll be able to do a side-by-side comparison over the next couple of years and see how the yields and expenses compare on the two halves,” he said. “If it works out, I might even be able to irrigate the other half without having to add more solar capacity.”

A Growing Interest

As the director of business development for Lad Irrigation, based in Washington state, Thad Taylor has witnessed a growing interest in solar-powered irrigation for some of the same reasons. As a dealer for Ag Solar and Valley Irrigation systems, Lad is a one-stop shop for the pivot, pump, and solar panels at the company’s eight locations around the state.

“We see three different things driving the interest in solar power,” Taylor said. “One is the USDA’s REAP grant and loan program, which currently pays up to half the cost of the solar panels. Another is the fact that customers in Washington can sell any excess power generation to the utility company at a retail or wholesale price, depending on the size of the system. Finally, a lot of our solar customers are potato or onion producers who deal with packing houses that have sustainability programs that trickle down to the producer. Consequently, they need to demonstrate that they are producing a crop without having a dramatic impact on the environment.”

Although most of the solar purchases Lad Irrigation installed have been 100 kW systems — which Taylor said are generally sufficient for a quarter-section pivot and pump — they can install a system for basically any need.

“We simply provide all the specs to Valley, including field size, terrain, etc., and Ag Solar gives us the system ready to install,” he explained, noting that the solar panels for a typical quarter section pivot occupy about a quarter acre. “The solar system comes with a 20-year warranty and can provide a payback in as little as four years,” he concluded. “After that, it’s basically free energy.”