Patent ID: 8393865

Claim:
A wind turbine rotor blade extension portion, comprising: a permanent framework, having one or more chord-wise members and a substantially span-wise member; a skin located over the framework to thereby generate a streamlined surface, wherein the extension portion comprises a first surface and a second surface, the first and second surfaces being spaced from one another at a proximal region of the extension portion and connected to one another at a distal region of the extension portion, wherein the extension portion is configured to transmit aerodynamic loads exerted on the skin, along the chord-wise members to a trailing portion of a rotor blade to which the extension portion is connected, in use, and wherein the substantially span-wise member is positioned at the distal region where the first and second surfaces are connected to each other; and a further span-wise member, located at one of a leading edge of the first surface and a leading edge of the second surface.