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Note: Percentiles are given according to turbine count Source: Wood Mackenzie

Figure 2-6 Evolution in specific power – U.S.

2.2.2 Blade scaling trends (power-production, weight, and cost) The potential power generated by a wind turbine is proportional to the square of the blade length, or the “swept area” of the rotor. Basic engineering principles suggest that the volume and weight of a blade should be proportional to the cube of the blade length, if the blade were scaled on a self-similar basis. This “squarecube law” has often been referenced within the wind energy industry to forecast an end to the progressive march toward larger turbines, because the weight and cost of the rotor blades would be growing much faster than the available power, and any LCOE improvements would be dependent on offsetting benefits realized in other parts of the wind turbine generator (WTG) system. While “square-cube law” is the common terminology, the true scaling relationship would be even less-favorable if the blades did follow the cubic scaling relationship. This is because the square relationship on power is only realized if the rated power of the WTG system scales up with area. If the rated power is constrained (as in the case of larger blades on a given WTG without increasing the rated power), the benefit is only realized at wind speeds below rated power. As blade lengths have continued to grow in the global wind energy market, the mass of the blades has not grown at a cubic rate. Turbine designers and blade manufacturers have innovated around the “square-cube law” to limit the growth of blade weight to approximately an exponent of 2.2, as illustrated in Figure 2-7.

DNV GL – Document No.: 10080081-HOU-R-01, Issue: C, Status: FINAL www.dnvgl.com

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Supersized wind turbine blade study  

R&D pathways for supersized wind turbine bladesSupersized wind turbine blade studyLawrence Berkeley National LaboratoryDocument Number: 1008...

Supersized wind turbine blade study  

R&D pathways for supersized wind turbine bladesSupersized wind turbine blade studyLawrence Berkeley National LaboratoryDocument Number: 1008...

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