<story><title>German institute successfully tests underwater energy storage sphere</title><url>https://arstechnica.com/science/2017/03/german-institute-successfully-tests-underwater-energy-storage-sphere/</url></story><parent_chain></parent_chain><comment><author>_nalply</author><text>I read about that about four days ago in a Swiss online newspaper [1] (German). The Lake Constance is a large lake (length 64km &amp;#x2F; 39mi) carved by the Ice Age Rhine glacier shared by Germany, Switzerland and Austria.&lt;p&gt;Since November last year a hollow concrete sphere with the weight of 20 metric tons has been sitting on the lake bed at a depth of 100m &amp;#x2F; 300ft. In times of excess power water is pumped out of the sphere and power is regenerated by inflowing water powering a turbine.&lt;p&gt;Now they are going to experiment with an even bigger sphere in the sea. Perhaps there will be some differences because of the salt water environment.&lt;p&gt;[1]: &lt;a href=&quot;http:&amp;#x2F;&amp;#x2F;www.tagblatt.ch&amp;#x2F;ostschweiz&amp;#x2F;Forscher-speichern-Strom-im-Bodensee-mit-Betonkugel;art120094,4918903&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;www.tagblatt.ch&amp;#x2F;ostschweiz&amp;#x2F;Forscher-speichern-Strom-i...&lt;/a&gt;</text></comment>
<story><title>German institute successfully tests underwater energy storage sphere</title><url>https://arstechnica.com/science/2017/03/german-institute-successfully-tests-underwater-energy-storage-sphere/</url></story><parent_chain></parent_chain><comment><author>ISL</author><text>This is amazing. To store temporary energy, you don&amp;#x27;t need a mountain range anymore. Instead, you can use nearby offshore trenches and continental shelves.&lt;p&gt;Open Google Earth. Look at the Philippines, the Arabian Peninsula, Hawaii, and eastern North Carolina. It&amp;#x27;s a perfect complement to solar energy in certain parts of the world.&lt;p&gt;Some good ideas are simple. This may be one of them.</text></comment>