Environmental Engineering Reference
In-Depth Information
Figure 7.48
Tip brake from Juul's Gedser windmill (left); Tip brakes on the
525 kW windmill in Hanstholm (right). In the early Riisager
windmills and windmills with early 5 m Økær blades the
tip brakes were “forgotten”. After serious accidents due to
runaways, tip brakes became mandatory. Økær blades became
tip brakes inspired by the Gedser windmill.
Learning from other's experiences with fibreglass blades LM
started producing extremely durable blades. Therefore by 2012,
8 m LM blades are still turning on old 75 kW wind turbines. Later
calculations showed that they had a calculated life expectancy of
70 years and the dimensioning was adjusted to a more realistic life
expectancy.
At the end of the 1980s Danish wind turbine manufacturers
were seriously weakened after the collapse of the American market
and hesitated to develop new, bigger windmills. But at LM they
were ready for the next step, where the size jumped from 200/300
kW to 500 kW. This led to the cooperation with the Folkecenter
about specifications and testing of the 17.2 m blade for a
500 kW joint development project, led by the Folkecenter (66%)
and the German wind turbine manufacturer Tacke (33%), as
partners. Tests that started in 1992 showed that the new LM blade
was successful.
Generally speaking, a blade supplier such as LM has set the
tempo of the growth of wind turbine sizes far more than the wind
Search WWH ::
Custom Search