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Innovation Feature

Farming a desert

Water-saving hydroponics systems will soon bring sustainable animal feed to herders in the Saudi Arabian desert.

13 February 2019

The vast numbers of Saudi Arabia’s camels — used for transport and as livestock — alongside other agricultural staples such as goats and sheep, make Saudi Arabia one of the world’s largest users of barley. With a forecast[1] of 8 million metric tonnes consumed yearly by livestock alone, all barley destined for feed is imported, due to the excessive water requirement of barley crops, which rely on wasteful irrigation systems. The inefficiency of the process was such a drain on water reserves that the country’s Ministry of Agriculture bans conventional barley production for feed purposes.

Researchers from KACST are now developing a new way to grow barley; with lower costs, faster production rates, perennial supply, less labour, and a much lower demand on Saudi Arabia’s precious water reserves.

A revolutionary farming tool

The technology, known as a hydroponic fodder system, involves growing mats of barley grass in channels within a highly controlled environment. The technique involves only supplying the barley with water and nutrients, without the need for a solid growth medium such as soil. While the system can accommodate a range of different cereal crops, such as oats and wheat, barley is most commonly used. And since the channels of the system can be stacked to make a vertical farm, this also reduces its land footprint; meaning high volumes of fodder can be produced in a relatively small space.

“A hydroponic fodder system would be very beneficial in Saudi Arabia because of the desert climate,” says Abdulrahman Alghannam, leader of the hydroponic fodder project. “The system is like a gift to us: It can be as big as a factory or small enough for a farmer to drag around to his animals.”

Alghannam’s team reports that a hydroponic system only takes between 1 and 2 litres of water to grow 1 kilogram of barley. In comparison, it takes 80 to 90 litres of water to grow 1 kilogram of green grass. Leftover water from a hydroponic fodder system can be recycled to conventional agriculture, where, thanks to its high nutritional content, it can be used to water pastures or vegetable plots.

The fodder grows quickly, producing a thick bed of grass in just five to eight days. In addition, a way for farmers to produce their own feed reduces reliance on other sources.

The feed produced by hydroponic fodder systems offers significant nutritional advantages over dry grain, with increased vitamin content, and a much higher level of digestibility. And as well as carbohydrates, hydroponic-grown fodder also offers fibre and protein to its animals. This higher quality of feed has the potential to improve the standard of the produce coming from the livestock and decrease the cost of feeding.

Reinventing the new

Hydroponic fodder systems are a fairly recent discovery; however, the technology is commercially available for purchase around the world, or a simple version can be built from scratch using basic materials. However, says Alghannam, KACST’s system must stand up to their country’s environment. “Most currently available systems are designed and manufactured in colder environments, so cooling isn’t an issue for them,” he says. “But our summer is very harsh.” This makes it difficult for these existing systems to maintain temperatures that suppress fungi and other microorganisms detrimental to barley.

Another issue arises when you consider that herds of camels, an important source of meat in Saudi markets, are spread across the desert. Alghannam and his team are therefore looking to design a portable version of their fodder system that can be dragged across adverse terrain. “This is an issue that does not exist in other countries,” he says. It’s also possible that large-scale dairy and beef farms could adapt the team’s hydroponic fodder system. However, Alghannam explains that these won’t be the main clients of their system due to the huge amount of yield they require.

“We’re taking a ready-made technology and modifying it according to our needs,” says Alghannam. Careful consideration must be given to the integration of the cooling system, airflow, and water. The design process of the cooling system could reduce much of the cost for farmers, says Alghannam.

To keep their fodder growing at the right temperature for the right price, the team will combine different energy sources, including conventional power and readily available solar power. An artificial intelligence program will control the cooling system by intelligently switching between alternate power systems and temperatures to keep the fodder within a comfortable temperature range for the lowest possible energy cost. “When you enter a room, you don’t say ‘this room is 25°C,’ you say ‘this is the right temperature for me,’” explains Alghannam. “This comfort zone can also be programmed into the program: When the cost of cooling goes higher, the temperature will go up, as long as it’s within the comfort zone for the fodder, to keep energy use economical.”

One of the major factors informing each step of the design process is cost; the fodder system needs to be produced, sold and operated at the lowest possible price point to ensure adoption by the country’s working farmers, says Alghannam. “We use low-cost technology so it doesn’t increase the system’s price.”

KACST’s hydroponic fodder system has already completed its design phase, and orders have been placed for the materials that will comprise the first prototypes. The team will begin assembling the first units in their test bed warehouse. Once complete, Alghannam and his colleagues will optimize their hydroponic fodder system to maximize its yield while minimizing the energy and operation costs. The team will also start constructing the system at various scales to meet the needs of Saudi Arabia’s agriculture industry.