An American startup is looking to turn seawater into drinking water using only the motion of the ocean. EcoH20 Innovations is currently working with the second prototype of its Swell Actuated Reverse Osmosis System (SAROS), a compact, portable and energy independent floating desalination system.
SAROS was designed with island communities in mind, where drinking water can be scarce and traditional desalination can be expensive, requiring burning fossil fuels that contribute to rising sea levels threatening many such communities. The relatively simple buoy-based system harnesses the energy of swelling and falling seas to pump sea water through a reverse osmosis system that makes it drinkable and then back to shore for storage via a hose.
"SAROS is different because, by using it, we can cut the cost currently associated withproducing fresh water in half," said SAROS' Director of Research & Development ChrisMatthews.
The SAROS team built a large, clunky-looking prototype to prove the concept works and then refined it into a second version that uses smaller and fewer components and is easier to transport and setup. Its creators say it can generate over 3,000 g (11,356 l) of drinking water from the ocean each day and can even desalinate water when the sea is relatively calm.
EcoH20 just launched an Indiegogo campaign to raise funds to help launch pilot projects that will see SAROS go in to service in Puerto Rico and Haiti.
The idea isn't totally new, however. A few years ago we covered the Canadian Odyssée desalinator project, which also attempted to further its research into a similar independent, wave-based system via a crowdfunding campaign. That effort fell well short of its funding goal and the project's website is now offline.
While the concepts seem very similar, it's notable that SAROS seems to be much further along in both technical and business development as it launches its crowdfunding campaign than Odyssée was.
EcoH2O says it is focusing on making a simple system with the primary mission of supplying drinking water rather than other things like electricity. Although the company does note that SAROS could also be configured to provide power, autonomously pump water to clean up oil spills and even filter plastic from the ocean.
The company has already partnered with corporate names like Autodesk and organizations working on the issue of water scarcity that seem to indicate it is moving forward. So far, the Indiegogo has already raised as much as the Odyssée crowdfunding campaign did in total and there's still a month left for SAROS to hit its $25,000 goal
As always, approach this and every crowdfunding campaign with a note of caution and do your own due diligence before contributing.
So lets say these things are 100 m apart. Can we agree that their effect reaches 100m out to sea? Can we agree the water is maybe 5 m deep. So the catchment of the thingy is 100x100x5m. That is 50,000 tons of water. Assume it gets replenished daily through water movement. So I extract 11,000 litres, or 11 tones, from 50,000 tons of seawater. That's 11/50,000 = 0.02%. So the machine will increase the salt concentration of that water by 0.02%.
Even if my estimate is out by two orders of magnitude, the figure is 0.2%. The concentration will increase from 3.5% (I believe, typical for seawater) to, wait for it, 3.507%
Hardly an ecological disaster! It's exactly what happens when the sea water evaporates and makes rain. The only place it might need a second thought is in a closed body of water (think Dead Sea), or one where there is very little exchange with the outside world.