The world’s first floating windfarm has taken to the seas in a sign that a technology once confined to research and development drawing boards is finally ready to unlock expanses of ocean for generating renewable power in Scotland. The £200m Hywind project is unusual not just because of the pioneering technology involved, which uses a 78-metre-tall underwater ballast and three mooring lines that will be attached to the seabed to keep the turbines upright. It will bring power to 20,000 homes.