The Wendelstein 7-X Stellarator is an experimental fusion reactor located in Greifswald, Germany. It is the world's largest stellarator, a type of fusion reactor that uses magnetic fields to contain and control the plasma within the reactor. The Wendelstein 7-X
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The Wendelstein 7-X (W7-X) reactor is an experimental stellarator built in Greifswald, Germany, by the Max Planck Institute for Plasma Physics (IPP), and completed in October 2015. Its purpose is to advance stellarator technology: though this experimental reactor will not produce electricity, it is used to evaluate the main components of a future fusion power plant; it was developed based on the predecessor Wendelstein 7-AS experimental reactor.