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overall system LCOE appear possible with use of LTA hybrid airships or controlled blade bending in rail transport. In other innovation pathways studied, blade-specific costs and performance contributed to increases in system LCOE indicating a broader, more systemic approach beyond just blades or different project site assumptions may be necessary to achieve lower system level LCOE. LTA hybrid airships, under our assumptions, were identified as having potential for blade-specific costs and performance able to lower system LCOE at both project sites, ranging between -2.1% to 0.4% depending on the site and blade length. LTA hybrid airships, if certified and commercialized, have potential to enable nationwide deployment of supersized blades and wind turbines in a cost competitive manner. Although there are active commercial efforts to bring this technology to market, there is significant uncertainty in the timing. Monitoring developments of this technology and seeking areas of collaboration to improve market development for wind energy (and many other applications) is recommended due to the potential for its enabling effects for supersized turbines. Currently, blade flexing during transport is not allowed because this loading method has not been established in the blade design and transport infrastructure has not been developed to enable it. R&D that enables limited and controlled blade bending in rail transport plus specialized road trailers appears able to achieve a neutral impact in system LCOE, ranging between -0.3% to +0.5%. However, there are geographic limitations on where controlled blade bending could be viable, thus this area of innovation may not have the nation-wide impact needed to achieve deployment of supersized wind turbines in regions where they are most applicable. This approach could theoretically take advantage of the designed flexibility characteristics inherent in wind turbine blades, provided these loads can be accounted for in the blade design as well as the rail and road transport infrastructure. This innovation area offers an opportunity for additional study of blades, the rail system and trailers, and related infrastructure to further assess the viability, management of reaction loads caused by bending, and blade design to achieve no decrease in long-term blade life expectancy. Segmented blades and on-site manufacturing pathways were found to increase system LCOE contribution, thus requiring greater savings in other turbine systems to achieve continued overall system LCOE reductions. Segmented blades offer features that other pathways are not currently able to provide, such as the ability to enable supersized blade deployment across the entire U.S., and blade joint solutions are under active investigation and early deployment by major OEMs. Other areas of innovation studied are further from market readiness. Additionally, there are likely opportunities to refine and optimize segmented blades to drive costs closer to a neutral LCOE impact, which for some regions, may be sufficient for wind deployment to be economically competitive. Segmented blades might become an optional feature available to the market along with monolithic blades and site-specific analysis would determine which option is most feasible and economically competitive. Based on current labor-intensive blade manufacturing technologies currently available, on-site (mobile) blade manufacturing faces economic challenges driven mainly by low tool/equipment utilization caused by time spent relocating and commissioning a mobile plant and elevated costs of local labor for hiring, training, plant commissioning, and first article manufacturing. These and other costs incurred each time the mobile plant is deployed represent significant challenges for any method of on-site blade manufacturing. Figure 9-5 summarizes the results of our pathway assessment in terms of impact on LCOE, our current opinion of commercial readiness, and geographic breadth each pathway could offer.

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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