sentences:  Carbon fibres have the added benefit of reducing the thickness of fibreglass laminate sections, further addressing the problems associated with resin wetting of thick lay-up sections.Wind turbines may also benefit from the general trend of increasing use and decreasing cost of carbon fibre materials.Although glass and carbon fibres have many optimal qualities for turbine blade performance, there are several downsides to these current fillers, including the fact that high filler fraction (10-70 wt%) causes increased density as well as microscopic defects and voids that often lead to premature failure.