TECHNOLOGY: RURAL SOLAR SYSTEM CUTS PUMP COST TO ZERO SNAPSHOT • Cattle growers Rob and Jen Brooks had a vision to drought-proof their property near Gympie in Queensland using an irrigation system that had zero running costs • The irrigation system was designed to be gravity fed • Pumps powered by solar panels transfer underground water to distribution tanks that gravity feed water to a pipe and riser system • The Brooks are now able to irrigate 35 ha of fodder crops without the need for – and cost of - power or council water.
Access to water and energy costs have become significant issues for the irrigation industry in Australia in the last few years. Some irrigators are deciding to take matters into their own hands by controlling costs and water access as much as possible within the farm boundary. Rob and Jen Brooks, who raise and fatten cattle on their property at Kilkivan near Gympie in Queensland, recently approached The Pump House and asked them to design an irrigation system with associated water storage pump capacity that would make them as independent as possible. Previously their enterprise was a dryland one. The challenge they gave The Pump House was to create an irrigation system that drought-proofed the property, gave the Brooks flexible management control and minimised or eliminated ongoing energy costs for pumping.
Peter Chadband (right) with Rob and Jen Brooks check out the solar panels installed to power transfer pumps.
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According to Peter Chadband, owner of The Pump House, the key components of the system decided on were as follows: • solar pumps • solar panels • tanks to store water • new sprinklers • radio control system. The first stage of this project has just been completed. Next is the installation of three more bores and the development of another 40 ha of irrigation.
Installation The source for irrigation water is an underground supply. Rather than pump straight from this supply, it was decided that storage tanks would be installed, and gravity would do the work to distribute it to the irrigation system. Four submersible pumps were installed at an average depth of 50 m to draw on the available bore water. They are powered by 206 solar panels, which enable water to be pumped to storage tanks at a higher elevation. The pump system has an inverter and pumps during daylight hours only. There are no batteries, but the system does have the option to be run by a genset during very overcast weather Two large storage tanks - 375,000 L each – were installed at a higher elevation (36 m) above the cultivation and 300 m from the irrigation system. The water is then stored to irrigate the crops. “All water is gravity fed so no power is required,” said Peter.
