A minute and a half of you time now may save you thousands of dollars on an automatic irrigation system. The Unpowered Terracotta Valve has a half inch inlet and outlet. It automatically controls sprinkler or drip irrigation.
The valve lets you adjust both the irrigation frequency and the dripper (or sprinkler) discharge during the irrigation. The irrigation frequency is adjusted by adjusting the float. The dripper discharge is adjusted by adjusting the control dripper.
The valve responds automatically to the on-site evaporation and rainfall. In fact the irrigation frequency is proportional to the net evaporation rate (that is, evaporation minus rainfall).
You can leave your irrigation application unattended for months on end. During the winter months the irrigation stops automatically while the rainfall is greater than the evaporation.
This low cost invention is more water efficient than a conventional smart irrigation controller that responds to weather data from the BOM. And nothing can be more energy efficient than unpowered.
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