Submitted to: Windpower
Publication Type: Proceedings
Publication Acceptance Date: 6/17/1997
Publication Date: N/A
Citation: Interpretive Summary: One source of power for pumping water for irrigation is using the power of the wind. Scientists at the USDA-Agricultural Research Service (ARS), Conservation and Production Research Laboratory in Bushland, TX, have been investigating ways of using the wind to pump water for irrigating crops for the past 15 years. In July 1995, two 10 kilowatt wind-electric water pumping systems were installed on farms located near the towns of Garden City, TX and Stiles, TX, for small scale irrigation. The amount of water pumped by the wind pumping system for cotton irrigation at the Garden City well (180 foot pumping depth) was satisfactory but the farmer could have produced more cotton and thus made more money if he had used the utility supplied electricity rather than the wind. Due to the intermittency of the wind, the volume of water was diminished. The amount of water pumped by the wind-electric pumping system for cotton irrigation at the Stiles well (340 foot pumping depth) was not sufficient to meet crop needs and either needed a larger size wind turbine or a pump with more stages. The flow rate - wind speed measurements determined at the USDA-ARS Laboratory were the same as those measured at Garden City and Stiles, so different pumps or wind turbines can be tested before they are installed at irrigation wells. At the current cost of electricity in the Garden City area ($.065/kilowatt- hour), buying this wind-electric water pumping system would not provide water at a lower cost. However, if the cost of electricity was higher ($0.12/kilowatt-hour) or the utility transmission lines had to be extended more than a mile ($12,000/mile), buying this wind-electric water pumping system would be a good investment.
Technical Abstract: A 10-kW wind-electric water pumping system was tested for field crop irrigation at pumping depths from 50 to 120 m. The wind turbine for this system used a permanent magnet alternator that provided variable- voltage, variable-frequency, 3-phase AC electricity which powered off-the-shelf submersible motors and pumps without the use of an inverter. Pumping performance was determined at the USDA-Agricultural Research Service (ARS) Wind Energy Laboratory in Bushland, TX for the 10kW wind turbine using a pressure valve and a pressure tank to simulate different pumping depths. Pumping performance was measured for two 10-kW wind turbines of the same type at farms near the cities of Garden City, TX and Stiles, TX. The pumping performance data collected at these actual wells compared favorably with the data collected at the USDA-ARS, Wind Energy Laboratory. If utility generated electricity was accessible, payback on the wind turbine depended on the cost of utility generated electricity and the transmission line extension cost.