Two UAE Firms Field-Test Water-Saving Greenhouse and Soil Technologies in Al Ain

CRETA Group and Dubai-based Raincatcher Technologies are among six finalists in the Al Miyah Challenge for Agriculture, which has a prize pool of AED 8 million and is moving its finalists into indoor and outdoor field trials in the UAE. The other finalists are M4Life, Krilltech, EF Polymer and Agri-Vit, according to the initiative's website. The two UAE companies described their systems to the state news agency WAM.

The stakes are practical for Gulf food security. Conventional fan-and-pad evaporative cooling in greenhouses uses an estimated 8 to 15 litres of water per square metre per day, which for a greenhouse the size of CRETA's trial means roughly 500 to 936 cubic metres over a 120-day summer peak, according to the figures WAM published. In sandy soils, Raincatcher said up to 90% of irrigation water can be lost to drainage below the roots or to evaporation.

CRETA's system treats the greenhouse as a set of linked climate zones inside a double shell. It pre-cools hot air through heat exchange with the ground beneath the structure, directs airflow, manages pressure differences and limits solar heat gain by passive means, cooling the air around the crops rather than the whole space. The company said the design has run without evaporative cooling water in summer or fuel-fired heating in winter in Mediterranean and milder climates, and that the Al Ain trial is adapting it to desert heat approaching 50 degrees Celsius.

On its 520-square-metre Al Ain site, CRETA said air temperature fell by about 12 to 15 degrees Celsius and cooling electricity use was about 30% to 40% lower than conventional systems, with a power demand of roughly 7 to 8 kilowatts. Its design target is to hold the crop zone at 28 to 32 degrees in peak summer while cutting cooling water by 85% to 90% compared with fan-and-pad systems; the company stressed these are design goals, not final measured savings. Installation costs about 20% to 30% more than a comparable conventional system, it said, offset by lower operating and maintenance costs and an underground structure designed to last more than 20 years.

Raincatcher's product is a biodegradable soil conditioner combining superabsorbent polymers and nutrients, injected near the roots to store irrigation or rain water and release it as the soil dries. It is potassium-based, so it does not add sodium to soils at risk of salinity, and works with existing irrigation. The company cited a published trial at the ICBA research centre in Dubai in which 27 treated date palms saved 85% of water and were watered every seven days instead of daily. In the challenge's sweet corn trial at the Sall Innovation Oasis in Al Ain, water use fell by about 20% to 25% against untreated plots.

Across field trials, Raincatcher said savings have ranged from 40% to 85%, with yield gains of 20% to more than 90% under water stress. It puts the average cost, including injection, at $7 per palm a year, $5 per orchard tree and $600 per hectare for field crops. Treatments last one to three seasons depending on the crop, and the product breaks down over about seven years on average, the company said.