Business Green: In what is being hailed as a world first, Norwegian energy giant Statkraft yesterday formally opened a prototype plant capable of generating zero-carbon energy through the power of osmosis. The plant at Tofte, outside Oslo, was opened by Crown Princess Mette-Marit of Norway and will be used for further testing and development research with a view to launching a commercial-scale demonstration plant within the next few years. The prototype power plant employs a semi-permeable …