Ribbon cutting ceremony in Boston today with CEO Aaron Mandell and Boston Mayor Thomas Menino. (news coverage from those cameras)
Couple interesting tidbits:
20% of electricity use in California is to move water, mainly feedling LA.
50% of domestic oil consumption in the middle east is for water production.
Oasys uses forward osmosis to purify sea water into drinking water. Today, this is typically done by boiling seawater (energy inefficient) or by reverse osmosis — using pumps to push sea water through a fine filter against the natural osmotic pressure which pushes the other way.
Forward osmosis runs with nature — it’s like tricking physics to be your friend. If the water on the other side of the membrane is “dirtier” than the sea water, then the fresh water component of the sea water will naturally pass across the membrane to reach equilibrium with no pressure or energy input required. Oasys uses ammonium salts as the draw solution to pull fresh water out of sea water. The draw solution is “saltier” than sea water. The key is to design a system where the subsequent removal of the “dirty” elements in the draw solution is cheaper and easier than removing the salt and pollution from the source water. Hence the brilliance of ammonium salts. They boil off at a temperature lower than the boiling point of water. Oasys can use low-grade waste heat, common in many industrial and power plants, to boil off the salts (which are then reused in a recycling loop), leaving pure water behind. This is heat that would otherwise be vented off because it is insufficient to drive a turbine. Nearly free water could be compelling, and even if the heat has to be generated, it might be the lowest cost/liter solution for desalination.
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