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A fiberglass composite reinforced with carbon nanofibers (CNF) at the resin-fiber interface is being developed for potential use in wind turbine blades. An energy and midpoint impact assessment was performed to gauge impacts of scaling production to blades 40 m and longer. Higher loadings force trade-offs in energy return on investment and midpoint impacts relative to the base case while remaining superior to thermoelectric power generation in these indicators. Energy-intensive production of CNFs forces impacts disproportionate to mass contribution. The polymer nanocomposite increases a 2 MW plant's global warming potential nearly 100% per kWh electricity generated with 5% CNF by mass in the blades if no increase in electrical output is realized. The relative scale of impact must be compensated by systematic improvements whether by deployment in higher potential zones or by increased life span; the trade-offs are expected to be significantly lessened with CNF manufacturing maturity. Significant challenges are faced in evaluating emerging technologies including uncertainty in future scenarios and process scaling. Inventories available for raw materials and monte carlos analysis have been used to gain insight to impacts of this development.

This chapter discusses the needs, challenges, and benefits of life-cycle assessment (LCA) in the environmental evaluation of polymer nanocomposites (PNCs). The chapter provides a detailed description of the LCA approach and describes the unique challenges surrounding the LCA of nanotechnology, specifically PNCs. The benefits of LCA and an overview of the major studies on the LCA of nanotechnology are also presented. Case studies on the LCA of carbon nanofiber (CNF)-reinforced polymer nanocomposites are presented along with a general discussion about the LCA of specific nanoproducts. The role of predictive approaches in the evaluation of emerging nanoproducts is also discussed.

Wind energy conversion (WEC) is dependent on wind power density, which increases with elevation and swept area of the rotor. Many components are readily scalable and size-independent; whereas, turbine blades have presented a new frontier in aerodynamic design. As the limits of glass fiber-reinforced plastics (GFRP) have been reached in this field, there is now a materials development problem in achieving outlooks for larger, more resilient WEC systems. A hybrid material is under development, which uses vapor-grown carbon nanofibers (VGCNF or CNF) to reinforce the interface of a glass fiber/epoxy matrix. This research aims to determine life cycle effects of substituting GFRP in large turbine blades with the hybrid material. A review of literature, databases, and industry reports on life cycle data for wind turbines helped to establish a baseline descriptive life cycle assessment (LCA). Trends of new installations were assessed to determine appropriate boundaries for comparison. Results indicate that cradle-to-gate processing energy of the new material is 1.4–7.7 times greater than for the original GFRP material on a MJ/kg basis under implicit assumptions of weight savings. Effects on energetic return on investment (EROI) vary from insignificant to substantial according to upstream process choices for CNF manufacture and solvent handling. All conclusions inherently assume that CNF-incorporation would lead to realizable technologies for substantially increasing either size or life span of turbine blades concomitant with weight savings. It is not yet substantiated whether replacement of long carbon fibers is advantageous both mechanically and energetically.