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Placing Solar panels on water

A floating solar array on an irrigation pond in Hyogo prefecture, Japan. Credit: Ciel & Terre International

In 2008 a winemaker in California named Greg Allen faced a big dilemma. He wanted to switch to solar energy but could not allot the two acres from his vineyard. So instead he decided to try something different. Allen proceeded to install 2,296 solar panels, however 994 of them where where placed on flotation devices that where tethered to the vineyards pond. This was the worlds first ever non experimental floating solar array!

Since then floating solar fields have taken Asia by storm especially in Japan and China. Japan has the most, they currently have 60 installations. And China currently has the largest floating solar installation. It is located near Huainan and sits atop a man made lake, the solar array is made up of 166,000 panels. This array currently produces about 40 megawatts, this is enough to power about 15,000 homes. The World Bank Report released a report estimating that floating solar array's potential could exceed 400 gigawatts.

An installation of a floating solar array usually consists of the following process. Solar panels that are on pontoons are tethered to the bottom of a reservoir, pond, or lake. After this cables whether they are floating or underwater carry the current to an onshore inverter, where it is then converted to an alternating current and sent to the grid. Some factors that engineers must take into account are wind speeds, waves and the longevity of the the panels and tethers.

Floating solar arrays may also offer distinct advantages in comparison to their land based solar arrays. The install process is much easier than roof, or land based solar installs. These solar arrays may also improve the environment by reducing the amount of water that is evaporated. Being placed on water may also help the solar panels be more efficient, since heat causes panels to lose efficiency. The cooling factor of the water may help increase the conversion rate by up to 20%. If you would like to read the original article head over to


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