Making energy-efficient upgrades to your irrigation system can save you energy and water, putting cash back into your pocket.
Energy Trust of Oregon offers rebates on irrigation hardware and can calculate incentives for pump and irrigation system upgrades to help realize energy-related savings on your farm.
Energy use in irrigation systems: The amount of electricity used in an irrigation system can vary depending on the type of irrigation system used. Every type of irrigation system has its own application efficiency, pressure, annual energy cost and initial equipment cost. These are all factors to consider when choosing a new system or updating an existing system. Energy Trust can help pay for the cost of upgrading and maintaining systems with rebates and calculated incentives. Visit www.energytrust.org/irrigation for more information.
Upgrading the energy efficiency of your irrigation system: Adding a variable frequency drive (VFD) to an irrigation pump can decrease energy use and increase the flexibility of irrigation systems. The VFD acts as a soft start thereby reducing water hammer. By regulating the pump, it requires less water, which can eliminate throttling and the use of flow bypass to deal with excess water. A VFD controls the water pressure entering the irrigation systems, allowing you to run only the needed irrigation systems at that time.
Linear or pivot irrigation systems can save energy over other less efficient systems. They have a high application efficiency, which uses less water. The increase in sprinklers can lead to better water uniformity which may improve crop yield. They run at a lower discharge pressure allowing the pump to lower its horsepower. The systems are less labor intensive than wheel lines, hand lines or travelers and it is possible to add remote start capability.
Low elevation spray application (LESA) and low energy precision application (LEPA) systems can be part of a linear or pivot system. These systems lower sprinklers closer to the ground or use sprinklers or bubblers that operate at the ground level.
Drip irrigation puts the water directly into the soil with very little moisture lost to evaporation. It is a highly energy-efficient choice for irrigation and is often a better way to irrigate the crop which can lead to greater yields.
Replacing sprinkler nozzles: Irrigation water typically contains grit and sand, which can wear the nozzle out. Nozzle wear depends on how often the irrigation system is used and the amount of sand or grit passing through it. Over time, nozzles wear out and are not always replaced as often as they should be.
Irrigation energy experts recommend replacing nozzles every five years. To test the wear of nozzles, place a drill bit snugly in a new nozzle of the proper size. If the same bit fits very loosely in an existing nozzle, the nozzle is worn and should be replaced. Worn nozzles cause more water to flow through than the intended design — overwatering crops, wasting water and energy.
Repairing leaking pipes: Sometimes repairing existing equipment is the most efficient way to go. Don’t throw out a good system if you can repair cut and press pipe on wheel lines, hand lines or portable main lines.
Dealing with leaky gaskets: Even small leaks waste enormous amounts of water and energy. For example, a leak of 1.7 gallons per minute adds up to over 1,200 gallons over a 12-hour set. On a larger scale, a 10 gallon per minute leak results in a loss of 7,200 gallons over a 12-hour set.
These leaks force the pump to work harder over time and cause equipment to burn out sooner than expected. Leaky gaskets can also affect crops, causing them to be over- or under-watered, resulting in uneven growth across the field.
Your local vendor is knowledgeable about equipment and can assist in purchasing and maximizing rebates to lower cost. To learn more about irrigation systems and available incentives from Energy Trust, visit www.energytrust.org/irrigation or call 503-928-3154.