SBIR-STTR Award

Wetzel Engineering, Inc., proposes research and development to engineer very large wind turbine rotor blades for land-based machines that avoid expensive and logistically challenging transportation requirements. The proposed solution combines two technologies: Sectional component-based assembly of large wind turbine rotor blades ( & gt;65m length) using design approaches adapted from aerospace composites manufacturing, Partial in-field manufacturing and final in-field assembly. This proposal responds to Topic 8a, specifically the request for proposals addressing . . . approaches to the assembly and installation of land-based wind turbines that overcome logistical and cost barriers . . . larger swept areas; and access to areas with higher class wind resource leading to an overall & gt;20% reduction in the cost of energy for land-based turbines. The objectives of the presently proposed applied research project are: Engineer and test the proposed technology for sectional component-based assembly of large wind turbine rotor blades ( & gt;65m length), Engineer and test the proposed technology for in-field manufacturing and assembly of large rotor blade sections, Develop commercially viable technology to aid land-based installations of wind turbines without limit on turbine size: Reduce the cost of energy & gt;20% by adopting this technology.

The utility-scale wind industry is evolving towards very large ( & gt;4MW) machines with blades longer than 70m for both land-based and off-shore installations. There is a rapid ramp in cost associated with ground transportation of blades longer than 65m, rising to a threshold that is considered practically prohibitive for blades longer than 75m. Managing the quality of such large blades using conventional manufacturing methods is also becoming increasingly challenging. As a product of the SBIR Phase 2 R & amp;D, Wetzel Engineering will create a Field-Assembled Component- Based Rotor Blade technology that addresses the above concerns. The blade is assembled in the field from factory-built sections sized to be easily transportable, and both the manufacturing and assembly are performed on open fixtures such that the quality can be inspected carefully before finish. During Phase 1, Wetzel Engineering identified the optimal configuration for sectioning a blade for more cost effective manufacturing, transportation, and field assembly. We also performed structural engineering of the major components of the blade, assessing the feasibility of the concept and identifying the potential cost and performance benefits of the technology. Phase 1 validated that the concept has merit and should be developed further in a Phase 2 SBIR project. During Phase 2 Wetzel Engineering will optimize the engineering of the structural components used in forming the blade through a program of comprehensive component and substructure testing. We will further validate and refine our understanding of the technology by building a 41m subscale test blade and subjecting it to static and fatigue testing. Finally, we will validate the scalability of the technology by engineering an 83m component-based blade for operation on a land-based 6MW wind turbine. Commercial Applications and Other

Benefits:
Wetzel Engineering, working with its Wetzel Blade manufacturing affiliate, will commercialize the technology by manufacturing 41 and 46m blades for the US domestic replacement blade market for aging 1.5-2.0MW turbines and by manufacturing 83, 90, and 100m blades for 6-10MW wind turbines for the worldwide off-shore and large land-based wind industry. Wetzel Engineering believes that the technology developed here will create a revolution in the engineering and manufacturing of rotor blades.