Japan has been diversifying its energy mix since Fukushima in March 2011, and is about to become home to the largest floating solar farm in the world. This will help to fulfil its need for new sources of electricity production, and also free up new space on an archipelago that is desperately short of land.Around 30 similar sites could be installed by mid-2015.Kyocera, the Japanese manufacturer of photovoltaic systems, and French SME Ciel & Terre, developer of the Hydrelio device, worked together to meet this twofold challenge. They created a platform by piecing a series of basic modules together (plastic cases filled with air and ballast), each comprising two moulded floats, the first one supporting the solar panel and the second one used to facilitate maintenance. This system is sufficiently strong to cope with typhoons and means that unused expanses of water can be converted into sites producing renewable energy. Such sites might include lakes formed by quarries, irrigation lakes or even water treatment plants.By May 2015, these two solar ‘islands’, whose total production capacity is 2.9 MW, will be installed on bodies of water in the Hyogo prefecture in the west of Japan. The aim is to supply 920 homes, i.e. to produce 3,300 MWh of electricity each year. And this could just be the start. The Japanese manufacturer is seeking to put around 30 floating photovoltaic sites (60 MW) in place across the Japanese archipelago by mid-2015. Having cherished the dream of putting a solar power station into orbit, Japan has now got its feet back on the ground. Or at least in the water!To go furtherA solar power station in space?