by Amit Malewar: Mankind has pursued an effective and simple way to use direct solar power to produce drinking water from salt water for centuries economically. The Suns River Still has patented an innovative method to desalinate water using solar power…
In 2017, the Louisiana-based manufacturer of solar stills announced a partnership with Dubai’s Merlin Farms to address food and water issues in rural desert areas of the Middle East, North Africa, Pakistan, and India.
Using revolutionary housing design and unique solar-powered desalination equipment from Suns River, Merlin Farms produces water and food at 6-10 kg per square meter per month, using saline well water.
The site is in the bare desert at a technology park associated with the American University of Sharjah, UAE. The process won the Sustainability Award at the 2019 WETEX conference in Dubai.
After centuries of failure, there is finally a way to use solar power to desalinate salty water, produce pure water for home and farm use and have housing in the raw desert.
The key energy driver is the Suns River desalination modules linked with Aquastill’s Membrane distillation – the process in which pure water is separated from contaminated water (salt water, for example) by means of evaporation through a membrane. The combination of Suns River and Aquastill brings productivity up to 50 liters/m2 or the equivalent of 6 times the solar energy input.
The venture is currently in the design phase to expand the 400 square meter demonstration site to produce 80 Cubic meters of pure water per day, expanding food production by 100 times. The site is off the electric grid and uses only solar and wind energy, meaning it has a zero carbon footprint. The demonstration site has been in operation for over two years.
The project uses 100% solar energy, feeds seawater, produces distilled water and dry salt, and demonstrates a whole new concept in economical desert living.
The Suns River equipment can be installed either on rooftop or ground location. The operation of the still is noiseless, and there are no internal moving parts. A simple low-pressure water pump is its most complex component. Its operation is automated and needs only occasional attention.
The demonstration facility consists of a battery of 15 modules – each measuring 1m wide (3.3 ft) by 2.5m (8.2 ft) long and elevated 2m (6.6 ft) above the ground – with a combined production rate of 0.45 m3/d (119 gpd).
Suns River CEO Hill Kemp says their solar stills can produce up to 12 L/m2/d or about three times more than a conventional still, using a combination of serpentine cooling tubes and an inclined feedwater heating surface in a recirculating, three-stage configuration. The system will be designed to operate on a day/night cycle, using the heated cooling water to produce a significant amount of the total water production overnight.
Suns River modules can use any saline stream from seawater, saline water, RO brine, etc. The process will soon debut growing commercial afforest in the bare desert, capturing 1.5 million tons of atmospheric carbon dioxide per square mile.
Using solar energy to meet current and future water needs makes sense because of the low carbon footprint, nil environmental impact, and the ability to process a wide range of bad water into good, drinkable water.