Today's Edition
ABU DHABI (WAM)
The Mohamed bin Zayed Water Initiative is field-testing finalist solutions from its Al Miyah Challenge for Agriculture that aim to reduce water consumption in greenhouse cooling and crop irrigation through engineered climate-management systems and water-retention technologies that enable efficient, controlled water use.
UAE-based CRETA Group and Raincatcher Technologies are finalists in the Al Miyah Challenge for Agriculture, a competition launched by the Mohamed bin Zayed Water Initiative.
The companies’ solutions address thermal loads inside greenhouses and water losses in sandy soils. Results and targets vary according to climate, crop and irrigation method, while both approaches can make use of existing agricultural infrastructure.
CRETA Group told the Emirates News Agency (WAM) that it has developed a proprietary, multi-zone greenhouse system integrating underground heat exchange, engineered airflow, differential-pressure management and passive reduction of solar heat gains.
Its dual-shell architecture defines interconnected thermal and pressure zones, enabling coordinated management of airflow and thermal loads, alongside heat exchange and thermal storage in the ground beneath the greenhouse.
The group explained that the system prioritises the microclimate around crops rather than cooling the entire space uniformly. This transforms the greenhouse into an integrated climate-management system, reducing reliance on water- and energy-intensive cooling and supporting agriculture that is less affected by outdoor conditions in both summer and winter.
It noted that, in the Mediterranean and milder climates tested, the system has operated without evaporative-cooling water in summer or fuel-fired heating in winter. Its Al Ain pilot is testing adaptations for desert conditions where temperatures can approach 50°C.
Peak-summer design targets include maintaining temperatures of 28–32°C in the crop zone and reducing cooling-water consumption by 85–90% compared with conventional fan-and-pad systems. These are design targets rather than final water-saving results measured for the pilot.
Based on conventional cooling-water consumption estimates of 8–15 litres per square metre per day, a greenhouse of the pilot’s size could require approximately 500–936 cubic metres over 120 peak-summer days. This provides the seasonal baseline against which the water-saving target is assessed.
The system manages air temperature and humidity before the air reaches the crops through controlled pre-cooling, integrated with underground heat exchange, thermal design and airflow pathways. The water-saving target includes water used for air preconditioning, while irrigation is assessed separately.
The group reported that its 520-square-metre Al Ain pilot recorded air-temperature reductions of approximately 12–15°C and cooling-related electricity consumption approximately 30–40% below conventional systems. The installation is configured to operate at an electrical demand of around 7–8 kilowatts.
The system can be integrated into existing greenhouses according to their structure and site conditions, or incorporated in full when new greenhouses are designed.
The group estimates that initial installation costs are approximately 20–30% higher than those of a comparable conventional system, depending on size, ground conditions and the adaptations required.
This is offset by lower operating and maintenance costs, including avoiding routine wet-pad maintenance and replacement. The underground infrastructure is designed for a service life exceeding 20 years.
The group explained that the payback period depends on installation costs, water and electricity prices, and operating hours.
Longer growing seasons or increased production could improve returns where demonstrated, it added, stressing that the system’s value should be assessed over its operating life.
Dubai-based Raincatcher Technologies told WAM that its product is a biodegradable soil improver combining superabsorbent polymers and nutrients. It is injected near the roots to store irrigation water or rainwater and release it gradually as the soil dries.
The company said water losses through drainage below the roots or evaporation in sandy soils can reach 90%. Its formulation absorbs several hundred times its own weight in water, forming gel pockets that attract roots and encourage a deeper, denser root system.
The company uses dedicated injection tools to protect the product from sunlight and surface evaporation.
Soil, climate and crop conditions are analysed to determine the appropriate dose and placement depth, while real-time moisture monitoring guides irrigation according to whether water savings or improved production is the priority.
Its approach received the Solar Impulse Foundation’s Efficient Solution Label in 2023.
The solution works with existing irrigation systems without requiring a change of crop or new infrastructure. It combines a consumable product with a technical service using specialised equipment and expertise.
Its potassium-based formulation adds no sodium to soils exposed to salinity and supplies potassium to plants as it degrades.
According to the company, a published trial at the International Center for Biosaline Agriculture (ICBA) in Dubai involving 27 date palms achieved an 85% water saving.
The treatment was applied within the top 50 centimetres of soil at the start of the 2020–2021 season, with irrigation guided by moisture sensors. Treated palms were irrigated once every seven days, compared with daily irrigation for untreated palms.
In a sweet-corn trial at Silal Innovation Oasis in Al Ain, water use was approximately 20–25% lower than in untreated plots, as part of the Challenge’s evaluation.
The company explained that annual crops grown under efficient drip irrigation start from a more efficient baseline, while savings increase under water stress and with perennial crops and sandy soils.
It reported water savings of 40–85% in field trials conducted in Türkiye, Morocco and Kyrgyzstan over five years, as well as yield increases ranging from 20% to more than 90% under water stress.
The company estimates average costs, including the product and injection, at $7 per date palm per year, $5 per orchard tree and $600 per hectare for field crops.
It reported water savings exceeding 80% for irrigated trees and ranging from 20% to 60% for irrigated field crops, alongside support for tree survival and production when rainfall is insufficient.
Investment is recovered through lower water and pumping-energy bills, longer intervals between irrigation and improved yields under water stress.
Effectiveness ranges from one to three growing seasons, depending on the crop, while the product degrades over approximately seven years on average, according to the company.
