Patent No. EP1658408 (titled "Tower For A Wind Turbine") was filed by Siemens Gamesa Renewable Energy Service on Aug 25, 2004. The application was issued on Feb 19, 2025.
A tower for large wind turbines (height >80m, output >1.5MW, rotor diameter >70m) comprises a nacelle and a rotor. The tower features an upper pipe-form section constituting at least one-sixth of the total height and a lower lattice tower portion. The lattice tower consists of multiple stacked sections, each comprising at least three hollow-profile corner posts and diagonal struts. A transition component connects the two portions, featuring an upper region for the pipe-form section and a lower region for the lattice tower. The lower tower portion's cross-section is larger than that of the upper portion, with the transition region designed for force-optimized adaptation of the cross-sections to minimize stress peaks and ensure structural stability.

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