Wind turbine rotor blade pre-staged for retrofitting with a replacement blade tip segment

1. A method for manufacturing an initial wind turbine blade that is pre-staged for subsequent retrofitting with a replacement blade tip segment, the method comprising:

forming continuous non-segmented pressure and suction side shell components having a tip end and a root end;

forming a spar structure within the pressure side and suction side shell components as a continuous non-segmented structure that extends from the root end to the tip end, wherein forming the spar structure includes:

placing a separate span-wise extending beam structure at a pre-defined span-wise location within the spar structure;

adhesively or mechanically attaching a root-end portion of the beam structure within and to the spar structure and leaving a tip-end portion of the beam structure extending within and unattached to the spar structure; and

wherein in a finished state of the initial wind turbine blade, the spar structure extends continuously and non-segmented from the root end to the tip end of the shell components, the beam structure is housed and extends span-wise within the spar structure with the root-end portion thereof fixedly attached to the spar structure and the tip-end portion thereof extending within and unattached to the spar structure.

2. The method of claim 1 , wherein the spar structure includes opposite shear webs, the step of adhesively or mechanically attaching the root end portion of the beam structure within and to the spar structure comprising attaching the root-end portion of the beam structure between and to the shear webs.

3. The method of claim 1 , further comprising retrofitting the initial wind turbine blade by fitting the replacement blade tip segment onto a blade root segment of the initial wind turbine blade by:

cutting away the shell components at a chord-wise line located where the unattached tip portion of the beam structure extends within the spar structure;

removing the spar structure from around the unattached tip-end portion of the beam structure such that the unattached tip-end portion of the beam structure is exposed and extends span-wise from the blade root segment of the initial wind turbine blade at the chord-wise line;

aligning and connecting the replacement blade tip segment with the blade root segment in a span-wise direction by moving a mating receiver section formed in the replacement blade tip segment ono the unattached tip-end portion of the beam structure extending from the chord-wise line; and

forming an aerodynamic surface at the chord-wise line between the blade root segment and the replacement blade tip segment.

4. The method of claim 3 , wherein the spar structure includes opposite shear webs, the unattached tip-end portion of the beam structure extending along and between the shear webs, and wherein the removing of the spar structure comprises cutting away the shear webs along the unattached tip-end portion of the beam structure.

5. The method of claim 3 , wherein the initial wind turbine blade is operational on a wind turbine at a field site, the retrofitting step performed with the initial wind turbine blade in an up-tower position on a rotor hub of the wind turbine.

6. The method of claim 3 , wherein the initial wind turbine blade is operational on a wind turbine at a field site, the method further comprising removing and lowering the initial wind turbine bade from a rotor hub of the wind turbine and performing the retrofitting step with the initial wind turbine blade in a down-tower position relative to the rotor hub.

7. The method of claim 3 , further comprising producing and maintaining an inventory of the replacement blade tip segments, wherein the retrofitting step comprises selecting and transporting one of the replacement blade tip segments from the inventory to a wind turbine at a field site.