Telescopic technology, patented by ESTEYCO, was initially tested in 2015 with an on-shore prototype without turbine at its top that was erected near Madrid. Some years later in 2.018 the first off-shore fully operational prototype was installed in Gran Canaria Island, becoming the first off-shore wind turbine installed in Southern Europe. Its main advantage was to avoid the need of heavy, scarce and expensive lifting means -heavy cranes or vessels- as they are not required neither for the tower nor turbine installations.
The solution is right now being implemented in Henan province, Continental China, achieving a hub height of 170m and supporting a 3.6MW – 155m rotor diameter turbine. It combines three concrete levels -heights ranging from 40 to 50m- with conventional tubular steel sections at its top. Concrete levels are cast-in-place at the ground level by means of a climbing formwork. These levels are arranged one inside the other, concentrically, prior to the beginning of the auto-lifting phase.
Tower ready for the beginning of the lifting works
The solution, from that moment on, will be using heavy-lift strand jacks always placed at 40-50m height, reusing them to lift one tower section after the other. Such recoverable jacks lifting each level will be supported by the one below, which also helps for guiding the lifting section as it rises, in a self-installing procedure in which the tower itself is the only supported structure required.
The whole construction process includes 3 stages:
On-site construction of concrete sections.
Upper steel level, nacelle and rotor assembly.
Self-erection system (2 lifting operations).
Both the concrete construction and the installation of the steel level have already been finalized, being the tower ready for the beginning of the self-lifting process, scheduled to be carried out during March, 2.021.
Some pictures from the work accomplished so far can be seen next:
After the erection of the tower and all the planned tests to be performed, it is expected that ESTEYCO’s self-lifting technology will be recognized as one of the more solid and cost effective alternatives to provide extra high HHs within the wind sector at a reasonable cost and timeline, as 1 tower/week rates are realistically expected to be attained in future serial productions.
