The opportunity for reducing the energy consumed in converting sea water to drinking water by 50% is high.  Research work currently under way is demonstrating this.  Applying the lessons from other industries appears to play a significant role in this. I was also initially surprised (but as soon as it was explained to me I understood why) that RO membranes will not likely be part of the solution. This is interesting.  Now though I need to familiarize myself with other more complex technologies and it’s taken me long enough to get my head around membranes. 

I also learned though that demonstrating significant energy reduction to be feasible is one thing, but doing it so that the long term cost is comparable to to existing technologies is another. That will be quite a journey. Much will depend on a sensible approach by regulators and owners in understanding their treated water quality objectives and the effect  ‘over specifying’ water quality objectives will have on energy consumption and greenhouse gas emmisions. 

A big part of the energy/water ballance will be the need to treat only to the required quality – perhaps several different qualities. This, in my view, has been a failing so far and we can do so much better through (in the words of Dr Terry Johnson) putting a bigger box around any project.   

Will we also be hindered by the interests of the membrane industry I wonder?….. 

Posted by: Gerry O’Toole