Energy Efficient Irrigation Strategies
By Maria Kanevsky
Agriculture is the backbone of our state, and keeping farmland well-irrigated is crucial for our agricultural producers. Farm irrigation methods and technologies can make a huge difference when it comes to maximizing productivity while minimizing costs.
Energy-efficient irrigation methods help farmers curtail unnecessary water use while growing the same produce, reducing their operating costs and increasing overall productivity. Above all, when choosing among irrigation methods and technologies, the most important considerations are overall cost, return on investment, convenience, and risk minimization.
One of the easiest ways to maximize energy efficiency, as many farmers have already done, is to replace old, inefficient diesel irrigation motors with electric motors. Typically, electric motors are about 90% efficient, while diesel motors are much less efficient, at 30%-40%. This means cost savings in the long run for farmers. Electric motors also have lower maintenance needs and can make use of a variable frequency drive (VFD) irrigation system, which helps further reduce costs.
VFD systems allow farmers to pump water at different rates, which maximizes irrigation throughout the day. A VFD system can control the speed of an electric motor by adjusting the frequency of the electrical power supplied to the motor. Since electric irrigation motors offer many benefits, the majority of U.S. farmers have switched from diesel motors to electric ones, although pairing the motor with a VFD system is still a relatively new agricultural trend.
Irrigation efficiency is not a one-time deal. After several years, the efficiency of irrigation pumps tends to decline. After five years, irrigation pumps are typically evaluated for performance efficiency. The evaluation can help inform decisions on the most cost-effective solution, whether making improvements to the existing pump or replacing it entirely. Irrigation pump tests usually assess the pump's discharge pressure, lift, water flow and power input. Regular testing of irrigation pumps can help ensure they are working as efficiently as possible. Upgrading irrigation hardware can also improve irrigation system performance. Replacing leaky sprinklers, for example, can help save a significant amount of water. Maintaining the overall efficiency of irrigation systems over time helps to reduce water use and save energy.
There are many new agricultural technologies that are part of the "precision agriculture" industry, including autonomous tractors, crop-monitoring drones, and robotic milking or weeding machines. Beyond existing irrigation technologies, Wi-Fi-connected crops is one type of precision agriculture irrigation technology. After placing Wi-Fi-connected sensors throughout a crop field, farmers can monitor conditions by using their smartphones or computers. Data on light, humidity, temperature and moisture are captured by the sensors. That data is automatically sent to a server for analysis, and then to a farmer's smartphone app. Using Wi-Fi-connected crops also allows farmers to remotely set automatic timers for their watering systems. With Wi-Fi-connected crops, there are several factors to consider, such as cost, range, bandwidth and power. One constraint of using Wi-Fi-connected crops is that the sensor range can be limited, which makes the technology only feasible for smaller farms. There are other network connectivity platforms that could be applied to irrigation management, such as cellular connection, satellites, LoRa and Sigfox, but Wi-Fi is by far the most commonly used.
As technology continues to improve, there will be new opportunities to support the agricultural sector. Replacing technology that uses on-site fossil fuels, such as propane and gasoline, with electricity-powered technology will improve energy efficiency and reduce local pollution.
Kansas’ electric cooperatives are proud to support their agricultural members and will continue to help them determine opportunities to improve and meet their energy efficiency goals.
Maria Kanevsky writes on consumer and cooperative affairs for the National Rural Electric Cooperative Association, the national trade association representing more than 900 local electric cooperatives. From growing suburbs to remote farming communities, electric co-ops serve as engines of economic development for 42 million Americans across 56% of the nation’s landscape.