Norway opened on Tuesday the world's first osmotic power plant, which produces emissions-free
electricity by mixing fresh water and sea water through a special membrane.
State-owned utility Statkraft's prototype plant, which for now will produce a tiny 2 kilowatts to 4
kilowatts of power or enough to run a coffee machine, will enable Statkraft to test and develop the
technology needed to drive down production costs.
The plant is driven by osmosis that naturally draws fresh water across a membrane and toward the
seawater side. This creates higher pressure on the sea water side, driving a turbine and producing
electricity.
"While salt might not save the world alone, we believe osmotic power will be an interesting part
of the renewable energy mix of the future," Statkraft Chief Executive Baard Mikkelsen told
reporters.
Statkraft, Europe's largest producer of renewable energy with experience in hydropower that
provides nearly all of Norway's electricity, aims to begin building commercial osmotic power
plants by 2015.
The main issue is to improve the efficiency of the membrane from around 1 watt per square meter
now to some 5 watts, which Statkraft says would make osmotic power costs comparable to those
from other renewable sources.
The prototype, on the Oslo fjord and about 40 miles south of the Norwegian capital, has about
2,000 square meters of membrane.
Future full-scale plants producing 25 megawatts of electricity, enough to provide power for 30,000
European households, would be as large as a football stadium and require some 5 million square
meters of membrane, Statkraft said.
Once new membrane "architecture" is solved, Statkraft believes the global production capacity for
osmotic energy could amount to 1,600 to 1,700 terawatt hours annually, or about half of the
European Union's total electricity demand.
Europe's osmotic power potential is seen at 180 terawatts, or about 5 percent of total consumption,
which could help the bloc reach renewable energy goals set to curb emissions of heat-trapping
gases and limit global warming.
Osmotic power, which can be located anywhere where clean fresh water runs into the sea, is seen
as more reliable than more variable wind or solar energy.