Griffith Hack Clean & Sustainable Technologies

World’s first osmotic power station opens by Griffith Hack

Norway’s state owned power company Statkraft has announced the opening of the world’s first experimental power station powered by osmotic pressure.

Energy is provided by the pressure created when salt water is placed next to fresh water and joined by an osmotic filter. There is a strong tendency for fresh water to dilute the salt water, and this ‘osmotic pressure’ is equivalent to 120 metres of water head pressure, which would be a useful sized hydroelectric plant. Osmotic power is the opposite of reverse osmosis desalination, which relies on high pressure and energy intensive pumps to force water from a salt water to a fresh water source.

The biggest challenge has been to develop osmotic filters that can withstand this head pressure, but researchers have developed a polymer composition to meet these requirements.

Would this work in Australia once it is at commercial scale? This would require a good supply of fresh water next to sea water, i.e a river mouth. One advantage of this power supply is rivers flow 24/7, with the unfortunate exception of the Murray River.

Mike Lloyd