Freshwater and food are two essential resources for human survival and well-being. However, both are becoming increasingly scarce and threatened by climate change, population growth, and environmental degradation.
How can we meet the rising demand for freshwater and food sustainably and equitably?
A novel project from the University of South Australia proposes a possible solution: floating sea farms that use solar energy and seawater to produce clean water and crops.
How floating sea farms work
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The floating sea farm is a self-sustaining solar-driven system that consists of two chambers: an upper layer similar to a glasshouse and a lower water harvest chamber.
The system works by evaporating seawater and recycling it into freshwater, which is then used to irrigate crops grown in the upper layer.
The lower chamber contains an array of solar evaporators that soak up the seawater, trap the salts in the evaporator body, and release clean water vapor into the air under the sun's rays.
The water vapor is then condensed on water belts and transferred to the upper chamber, where it is stored in tanks or distributed to the plants.
The upper chamber is designed to grow various vegetable crops, such as broccoli, lettuce, and bok choi, without any human involvement or additional clean water irrigation.
The crops are grown on floating platforms that can adjust their height according to the water level.
The plants can also benefit from the natural light, temperature, and humidity provided by the glasshouse-like structure.
The system is powered only by solar light and does not require any external energy or water sources. It is fully automated, low-cost, and easy to operate. It can be deployed on any seawater surface, such as oceans, lakes, or reservoirs.
How floating sea farms can benefit humanity and nature
The floating sea farm project aims to address the global challenges of freshwater and food scarcity in an innovative and eco-friendly way.
According to the researchers, the system has several advantages over conventional methods of desalination and agriculture:
It can produce freshwater and food simultaneously, without competing for land or freshwater resources.
It can reduce greenhouse gas emissions and water pollution, as it does not use fossil fuels or chemicals.
It can enhance food security and nutrition, as it can grow diverse and healthy crops all year round.
It can adapt to climate change and sea level rise, as it can float on any water surface.
It can create new economic opportunities and social benefits, as it can provide income and employment for local communities.
The researchers estimated that the system can account for 31% of the total freshwater demand and 12% of the total food demand in the region while occupying only 12% of the seawater area.
They also suggested that the system can be scaled up by using multiple devices or increasing their size.
The researchers envisioned that floating sea farms could become a common sight in the future, providing a solution to feed the world and ensure freshwater by 2050.
They hoped that their project will inspire more research and innovation in this field, as well as more collaboration and support from stakeholders such as industry, government, academia, and civil society.
