I have publised a short YouTube video (duration 1:40) about the Unpowered Terracotta Irrigation Controllerhttps://www.youtube.com/watch?v=M0zoSQ...
Published on by Bernie Omodei, Owner at Measured Irrigation
https://www.youtube.com/watch?v=M0zoSQmJeug
The Unpowered Terracotta Irrigation Controller saves more water than a conventional irrigation controller and halves the cost of a drip irrigation system. It lets you adjust both the irrigation frequency and the dripper (or sprinkler) discharge. The irrigation frequency is adjusted by adjusting the float and the dripper discharge is adjusted by adjusting the control dripper. The controller responds automatically to the on-site evaporation and rainfall. You can leave your irrigation application unattended for months on end. Nothing can be more energy efficient than unpowered.
Unglazed terracotta pots have been used for water-saving irrigation since the first century BC. This remarkable invention is uses an unglazed terracotta pot as the centrepiece of a state-of-the-art unpowered irrigation controller. The irrigation starts automatically after sufficient water has evaporated from the surface of the porous terracotta pot. The irrigation stops automatically when the control dripper has replaced the evaporated water.
The Unpowered Terracotta Irrigation Controller is suitable for automatic sprinkler irrigation or drip irrigation, and operates in the pressure range 10 kPa to 800 kPa. This is a game-changer for automatic irrigation from a rainwater tank without using a pump.