Abstract: A wind turbine has a generator (7) with a connected rotor (3) having a hub (4) and blades (5) rotatably connected to the hub for adjusting the pitch angle. In a method of operating such a wind turbine under climatic conditions, where there is a risk of icing on the blades and no or weak wind, the generator is used as a motor for driving the rotor and the pitch angle of the blades is adjusted to ensure that the resulting wind substantially hits the leading edge of the blades. It is thus ensured that any icing only occurs on the leading edge of the blades. Any ice formed may be removed by means of de-icing in a known manner.

Abstract: Wind turbine blade (10) including adjustable lift-regulating means (12, 13, 15, 17, 19, 21) arranged on or at the surface of the wind turbine blade (10), said lift-regulating means being provided with activating means by means of which they can be adjusted and thus alter the aerodynamic properties of the blade (10). The lift-regulating means (12, 13, 15, 17, 19, 21) and the activating means are adapted and arranged such that by activation of the activating means, the lift can be reduced in a zone extending in the longitudinal direction of the blade (10) from a first position adjacent the blade tip (14) to a second position between the first position and the blade root (16) and this second position is variable in the longitudinal direction of the blade (10) by adjusting the activate means. The lift-regulating means are formed of at least one flexible flap (12, 13, 15, 17, 19, 21).

Abstract: A method of transporting and storing a wind turbine blade (1) including a blade root (10) and a blade tip (4), where the wind turbine blade curves in the unloaded state in such a manner that the blade (1) presents a substantially concave face (30) and a substantially convex face (12), and such that said blade tip (4) is spaced apart from the longitudinal central axis (28) of said blade root (10). By the method, the wind turbine blade (1) is prestressed by means of prestressing means (2, 5, 6, 9, 13, 16, 17, 21, 22, 23, 24, 25, 26, 33) at a distance from the blade root (10) in such a manner that the blade tip (4) is brought closer to the longitudinal central axis (28) of the blade root (10).

Abstract: A wind turbine has a generator (7) with a connected rotor (3) having a hub (4) and blades (5) rotatably connected to the hub for adjusting the pitch angle. In a method of operating such a wind turbine under climatic conditions, where there is a risk of icing on the blades and no or weak wind, the generator is used as a motor for driving the rotor and the pitch angle of the blades is adjusted to ensure that the resulting wind substantially hits the leading edge of the blades. It is thus ensured that any icing only occurs on the leading edge of the blades. Any ice formed may be removed by means of de-icing in a known manner.

Abstract: A wind turbine rotor blade (10) comprising one or more means (4) secured to the blade (10) for changing the profile thereof depending on the atmospheric temperature. The means comprises at least one laminate having at least two layers of materials with differing thermal expansion coefficients.

Abstract: The invention relates to a wind turbine blade (14) of fibre-reinforced polymer. The blade (14) is divided into an inner end portion (15) including the blade root and made substantially from fibre glass-reinforced polymer, and an outer end portion (17) including the blade tip and made substantially from carbon fibre-reinforced polymer.

Abstract: The invention relates to a wind turbine blade and a transitional shell blank for the manufacture of the shell of a wind turbine blade, the blade or the transitional shell blank being made of fibre-reinforced polymer including a first type of fibres (1, 3, 6) of a first stiffness and a first elongation at breakage, and a second type of fibres (2, 5, 7) of a different stiffness and a different elongation at breakage. According to the invention the two types of fibres are distributed in the polymer matrix. When seen in a sectional view perpendicular to longitudinal direction of the blade or the transitional shell blank, the quantitative ratio of the two types of fibres varies continuously in the longitudinal direction of the blade or of the transition shell blank.

Abstract: A wind turbine rotor blade (10) comprising one or more means (4) secured to the blade (10) for changing the profile thereof depending on the atmospheric temperature. The means comprises at least one laminate having at least two layers of materials with differing thermal expansion coefficients.

Abstract: Wind turbine blade comprises a first (1) and a second (2) electric conductor extending in the longitudinal direction of the blade (25), and one or more electric heating elements (4) for heating the surface of the blade. The heating elements (4) are connected to the first and the second electric conductor. At its tip the wind turbine blade (25) is provided with a lightning receptor 5 for catching lightning, and the lightning receptor (5) is electrically connected to a third (3) conductor earthed so as to be able to carry the current from a stroke of lightning to the earth. The first and the second conductor are connected to the lightning receptor through spark gaps adjacent said lightning receptor and connected to earth through spark gaps adjacent the blade root.

Abstract: A windmill rotor of the front-runner type and airfoil type wind blades therefor in which the blade tips have a longitudinally forwardly curved configuration. The curvature solves the problem of inward flexure of the blade in strong wind conditions, without requiring modification of the manner in which the rotor as a whole is mounted in order to avoid having the blade strike the windmill tower under such strong wind conditions.

Abstract: A wind turbine blade with a lightning conductor, where said lightning conductor is formed by one or more oblong strips (1, 2, 3) of carbon fiber-reinforced plastics preferably forming part of the wind turbine blade. In this manner the oblong strips (1, 2, 3) of carbon fiber-reinforced plastics both reinforce the blade and divert the lightning.