Large amounts of energy flow of all rivers in the world to the sea Statkraft has decided to imprison this energy with an old technology. Within the huge paper mill in Tofte Sodra Cells (Hurum), along the Oslo fjord, Statkraft is building the first "hydraulic marine" that should work in spring 2009. This is a prototype that can generate enough energy to operate a baking sheet or a fan.It is in the 70 years that an American researcher Sidney Loeb, has developed a method of energy to desalinate seawater using membranes. Meanwhile, he realized that if we applied the process in reverse, it could produce energy. This was

a useful starting point for researchers from SINTEF, who watched more closely this theory, but quickly realized they had to rely on an industrial structure. "In 1997, they asked us if we were interested to develop this concept with them," says Stein Erik Skilhagen, project manager at Statkraft. Thus Statkraft has invested 100 million NOK (about 11 million euros) to develop this idea, which has not yet reached the commercial stage. There will be 2000 m2 of membrane surface in the prototype built Statkraft and will generate about 10 kW, provided that the membranes are somewhat more effective. A plant size, including 5 million m2, will produce around 25MW, the power consumption of approximately 10,000 households in Norway. Statkraft has calculated that it could produce 12TWh/an from the hydraulic marine, 10% of the Norwegian energy consumption. Overall, Statkraft evaluate the potential between 1 600 and 1 700 TWh. "This is not what will save the planet, but this may be one factor among others," says Skilhagen. For this technology is commercially viable, it must membranes which "generate" 5 watts/m2. At present there is around 3 watts/m2. "Between 1997 and 2000, we have tried various types of membranes that generate 0.1 watt/m2. We realized that we should develop our own research on membranes. What is important is to get membranes more efficient, "says Stein Erik Skilhagen.