A crucial factor affecting the energy yield of a wind turbine, besides air density and wind speed, is the rotor swept area over which the wind flows. This swept area, in turn, is determined by the length of the rotor blades. The industry trend is clearly heading in the direction of longer and longer rotor blades. The Siemens rotor consisting of three 75-meter rotor blades has a diameter of 154 meters and covers a surface area of approximately 18,600 square meters, equal to about two and a half soccer fields. The Siemens 6 megawatt wind turbine will generate about 65% more energy using the 75-meter rotor blade compared with the Siemens 3.6 Megawatt bestseller using the earlier blade with a length of 58 meter.
Dong Energy ordered a total of 300 6-megawatt wind turbines featuring the record rotor measuring 154 meters in length. These wind turbines are to be installed in wind power plants off the British coast between 2014 and 2017.
With a full range of capacity options (85AH-3300AH) and voltage configurations to choose from, Rolls Battery maintenance-free 2V, 6V & 12V AGM and broad range of 2V GEL models offer a valve regulated lead acid (VRLA) battery option with the same dependable energy storage and heavy-duty construction customers have grown to expect from the Rolls brand for over sixty years. Installed in off-grid, grid-tied or backup float applications, these sealed batteries require minimal ongoing maintenance and provide a versatile energy storage solution for remote or confined installations. Rolls Battery AGM and GEL battery lines deliver superior cycle life and are backed by an industry-leading warranty.