Wendelstein 7-X in Greifswald is a fusion experiment of the Max Planck Institute for Plasma Physics. Its design rests on an optimization concept calculated in advance. The largely worked-out application for EU support was submitted in August 1990. Construction of the new institute building began in 1997. The machine produced its first plasma on 10 December 2015.
Because of the long construction phase, the total cost of the Greifswald site was more than double the original estimate. One experimental phase in 2018 had a clearly stated aim: die Richtigkeit der berechneten Optimierung experimentell zu überprüfen, to check by experiment that the calculated optimization was correct.