Modular wind turbine blades

A modular wind turbine blade comprising first and second blade modules connected together by an elongate connecting member, each blade module comprising:

• an outer shell having a laminate structure, the outer shell defining an outer surface of the blade module, and a connecting region of the outer shell defining an interface end of the blade module;
• a longitudinal spar structure embedded in the laminate structure of the outer shell, the spar structure having a tapered portion in the connecting region of the outer shell, the thickness of the tapered portion decreasing progressively moving towards the interface end of the blade module, such that a tapered recess is defined in the outer surface of the blade module in the connecting region, the tapered recess accordingly having a depth relative to the outer surface of the blade module that increases progressively moving towards the interface end of the blade module,
• wherein the first and second blade modules are arranged end-to-end with their respective interface ends in abutment and their respective tapered recesses aligned to define a continuous double-tapered channel spanning the connecting regions of the first and second blade modules,
• wherein the elongate connecting member has a double-tapered structure comprising first and second tapered ends, the double-tapered structure being complementary in shape to the double-tapered channel,
• and wherein the elongate connecting member is bonded in the double-tapered channel and bridges the longitudinal spar structures of the first and second blade modules thereby connecting the blade modules together.