The scarcity of freshwater resources and the demand for water supplies is critical in many arid regions of the world. Desalination of water is an efficient method to produce fresh water from brackish water. Desalination is an age-old practice in ancient times, many civilizations used this process on their ships to convert sea water into drinking water.

Famous methods of desalination include distillation and reverse osmosis. These methods have sure proven success in desalination of water. But they are costly.

Desalination of inland brackish water requires an efficient alternative to reverse osmosis and distillation. The evaporative method can be used for desalination with zero liquid discharge. But it requires a huge amount of heat.

The 20-hectare expansion project of solar-steam based desalination, Australia. Image Source: Wikimedia Commons

Solar steam based desalination is an efficient evaporative method. Harnessing solar energy to produce fresh water is a cost-effective and a sustainable method. Large-scale solar steam based desalination projects are being carried out throughout the world to meet the demands of fresh water and renewable steam.


The project “Solar Steam on Demand”

Sunvapour is a California based company that provides technology to produce solar thermal energy. The company has their own patented product to produce solar steam.

Their Project “Solar Steam on Demand” was selected to receive a $1.5 million award from the U.S. Department of Energy, Solar Energy Technologies Offices to advance solar-thermal desalination technologies. This technology can expand the market for producing freshwater from alternative water-sources.

The best part of this project is it enables a continuous operation of desalination equipment even when the sun is not shining. The project will be using a unique solar steam generator to produce 11 bara saturated steam pressure. At this pressure, desalination of brackish water takes place. These steam conditions are required for most of the industrial applications especially food industries.

The prototype solar steam plant will first be deployed for a food processing application where there is an urgent need for greenhouse gas reductions.

“Sustainability remains a concern for California League Food Producers members. With their Solar Steam on Demand project, Sunvapor is taking an urgently needed step towards offering a sustainable source of both clean water and energy to our members.”- John Larrea, the Director of the Governmental Affairs at the California League of Food Producers.

Project engineering will start in the fourth quarter of 2018, and the completed prototype plant with integrated storage will be tested for performance through the first quarter of 2021. The project will be a reference for the development of other solar steam plants in the future.