Open Field Demonstration

An open-field EPIC installation at the Al Dahra farm in Al Ain, built in late November 2010 alongside the greenhouse trial. It was built to prove the system on open ground across the farm's mixed crops: vegetables, alfalfa and forage grass. Data collection began at the end of January 2011.

Open field is the harder case, with no shelter from wind or sun and far higher evaporative demand than under glass. The farm also had a fertiliser problem. In a conventional system fertiliser seeps into the ground. Inside the EPDM liner it is held once applied and released as the plant uses it, which keeps it out of the groundwater.

Unlike the hand-dug greenhouse trenches, one large area was excavated and covered with EPDM liner. EPIC chambers were fitted in rows across it, then gravel and sand. The area was split into three cells so that water levels could be tracked separately during the demonstration. In normal operation, the same area or a larger one could run from a single cell. Extra tanks, water meters and pumps were installed only to collect and analyse data.

The project brief records that plants under EPIC were greener and healthier. In the first four to six weeks the drip system lost about 10% of its plants, possibly to nematodes, while EPIC lost none. The farm also reported a water saving of about 82% on its greenhouse installation, in line with what was predicted. The date palm plots were expected by the end of March 2011.