Dear Mr. Lois, your approach is surely a nice possibility for some niche applications and for areas with limited specific water demand. But your statements against using reverse osmosis are not retraceable.  What is "excessive ​energy" ? Specific, only RO process related, 2.5 to 3.2 kWh per m³ of permeate for middle sized and especially bigger SWRO desalination plants is surely not excessive. For which kind of seawater you specify the osmotic pressure ? As we all know seawater with about 35,000 mg/L (average for oceans) has an osmotic pressure of 25 bar. To operate SWRO desalination plants about 60 to 70 bar are usual figures, but depending also on the permeate recovery rate, feed water temperature and quality, age and fouling status of the membranes, etc., etc.. So we should be more precise.   What are "deserted shores" ? Please be informed, that if seawater reverse osmosis (SWRO) desalination plants are well designed, manufactured and adequately operated, for bigger plants (e. g. more than 50,000 m³/d) the costs are in the range of less than one (1) Euro per m³ of potable water. Due to the different factors influencing OPEX and CAPEX for smaller units this could be higher. But in one point we agree: the costs for such kind of plants could be optimized if sustainable modern systems allowing to contribute to increase the resource efficiency and to reduce overall costs would be used for seawater intake and remineralisation of the permeate.   www.petersconsulting.eu

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Dear Mr. Lois, your approach is surely a nice possibility for some niche applications and for areas with limited specific water demand. But your statements against using reverse osmosis are not retraceable. 

What is "excessive ​energy" ? Specific, only RO process related, 2.5 to 3.2 kWh per m³ of permeate for middle sized and especially bigger SWRO desalination plants is surely not excessive.

For which kind of seawater you specify the osmotic pressure ? As we all know seawater with about 35,000 mg/L (average for oceans) has an osmotic pressure of 25 bar. To operate SWRO desalination plants about 60 to 70 bar are usual figures, but depending also on the permeate recovery rate, feed water temperature and quality, age and fouling status of the membranes, etc., etc.. So we should be more precise.  

What are "deserted shores" ?

Please be informed, that if seawater reverse osmosis (SWRO) desalination plants are well designed, manufactured and adequately operated, for bigger plants (e. g. more than 50,000 m³/d) the costs are in the range of less than one (1) Euro per m³ of potable water. Due to the different factors influencing OPEX and CAPEX for smaller units this could be higher.

But in one point we agree: the costs for such kind of plants could be optimized if sustainable modern systems allowing to contribute to increase the resource efficiency and to reduce overall costs would be used for seawater intake and remineralisation of the permeate.  

www.petersconsulting.eu