Aerodyn Study Confirms That Prepreg Spar Caps Are Lighter Than Infused Spar Caps And Can Provide a more Cost-Effective Solution

Hexcel recently initiated a design study with aerodyn Energiesysteme GmbH to evaluate the weight-saving implications of producing wind blade spar caps from prepreg rather than the resin infusion process. The spar cap is the major load-carrying structure within a wind blade. 

Aerodyn was selected for the trial due to track record of successfully developing wind energy converters and their individual components. Since 1983 aerodyn has been involved in numerous international projects and developed new concepts that have led the way in wind energy production. Converters developed by aerodyn are installed in all five continents, generating power in a reliable and environmentally friendly way.

For the Hexcel study the aerodyn 50.3m 2.5MW Windclass III blade design was selected. This blade is currently manufactured using resin-infused glass fiber and is commercially available and in operation. Hexcel’s HexPly® M9.6F/32%/1600+50/G+F prepreg was selected for the comparative trials. This 1600 g/m² FAW glass UD material uses 2400 tex E-glass filament rovings and contains a 50g/m² glass fleece to support the evacuation of air during the cure of the lay-up structure. The mechanical performance of the material was tested by IMA Dresden.

After carrying out a number of tests and validating the results, the aerodyn study concluded that replacing a glass fiber infused spar cap with a prepreg design will result in a weight reduction of approximately 400kg in spar structures - 3-4% of the total blade weight - mainly due to the superior strength and stiffness that Hexcel’s glass UD prepregs provide in both tensile and compression mode. The use of prepreg rather than infusion could therefore result in a total cost saving of approximately 1,300 Euros per blade, based on potential savings in material costs and man-hours in production. These proven weight and cost savings demonstrate the clear advantages provided by prepreg technology for new blade designs - and may also provide attractive paybacks on existing designs. Furthermore, Hexcel is developing new advanced glass prepreg materials that should offer even greater potential for cost-savings - both in material consumption and in lay-up labour requirements - due to the even higher mechanical performance.

Commenting on the results of the study, Andrea Domenichini, Hexcel Senior Vice President and General Manager for Wind Energy said: “The aerodyn study confirms and reinforces that the use of prepreg brings significant performance advantages as well as weight-savings when compared with infusion technology. Combined with the cost-saving advantages, prepreg technology will be even more compelling for the wind blade designs of the future.” To find out more about the study please contact manfred.schoeflinger@hexcel.com


Communications Contact:
Rachel Owen
Tel: +44 1223 838370
rachel.owen@hexcel.com

Wind Energy Contact:
Manfred Shoeflinger
Tel: +43 (7229) 772 220
manfred.schoeflinger@hexcel.com