JEC COMPOSITES MAGAZINE - Issue #116 - October 2017 - 47

Evolution of technologies and materials used in wind turbine blade manufacturing

Fig. 4: Blade
cost and sparcap
weight differences based on
STRUCTeam's
80m reference
blade, STL806MW

Fig. 3: Blade weight and blade cost differences based on
STRUCTeam's 80m reference blade, STL80-6MW

preventing its broader adoption. From a
technical standpoint, achieving consistent quality has always been a challenge
that was further aggravated by the
mismatch in process of choice for carbon
and glass fibre. Glass fibre is essentially
processed with a resin infusion process
while carbon fibre is more suited to
prepreg and pultrusion. The opportunity
for carbon fibre adoption lies in its ability
to be processed in a similar way to glass
fibre, therefore enabling hybrid blades
using both glass and carbon fibre in their
spars. In this case, the fibre volumes
available could be leveraged in a lower
cost of energy, therefore ensuring the
supply chain is a managed risk for the
blade manufacturer or OEM.

What is next?
Wind energy generation in itself is very disruptive. It is one of those industries where
disruption enables development and it has
a major influence on the everyday life of
humanity and many other sectors as well.
Let us just think of transitions like animal
force vs. steam vs. internal combustion vs.
electric, or coal vs. nuclear vs. renewables
in energy generation.
There are a few candidates for the next
big disruption in material technologies.
The most obvious candidate is carbon
fibre. Although it seems straightforward
in principle, with its great performance
attribute and its good track record in
the sector, the adoption of carbon fibre
has stalled for various reasons. The lack
of standards and the small volume of
fibre available (compared to glass fibre
availability) have proven to be hurdles

The next technology candidate, the
manufacture of sparcaps using pultrusion,
embeds many of the features seen in the
three examples. To this end, STRUCTeam
has formed the Pullwind consortium
to develop and enable its adoption
addressing the supply chain, the material
performance, the design and manufacturing challenges associated with the use of
pultrusion for wind turbine blades. The
Pullwind consortium members are Olin
(resins), CPIC (glass fibre) and other
key suppliers. Advanced negotiations
are taking place to complete the partnership with the final addition of a carbon
manufacturer. Pultrusion enables a cost
reduction of blade manufacture through
its supply chain that can be tailored to
the OEM requirements for either local
content or low-cost production (Figure
4). Additionally, improved mechanical

performance leads to less material being
used and associated, lowering CAPEX for
the blade manufacturer and also allowing
for glass and carbon fibre to be processed
using a common process. The selection
of this technology by an industry leader
for a number of years also demonstrates
its potential to grow as an innovation and
displace the current methods for manufacturing sparcaps.
Finally, further evolutions for resins are
expected. Epoxy suppliers are continuously working to improve their current
systems with a core focus on cycle time
and cure improvement. Polyurethane is
also being explored, essentially due to the
potential in cycle time reduction, but yet
to remain proven in a series application
and on the scale required to supply the
delivery of 50GW+ each year. One possible disruption is the use of thermoplastic
resins in blades, however they have been
more suited to smaller parts traditionally.
Conclusion
In such a cost and performance driven
industry, small gains can have a significant
impact. As shown, the speed of technology adaption in the wind sector is immense
and within a decade, evolutions have set
a different standard. The technologies
discussed might not be deemed disruptive
on their own rights when looking for the
ten-fold benefit gain discussed, however
these evolutions combined together could
be considered disruptive.

N°116 October 2017

More information :
www.structeam-ltd.com

/ jec composites magazine

Feature Wind energy

cess factors for three different material
technologies. The common element is
essentially linked with lowering cost for
any successful evolution. While taking
a closer look, it is clear that the wind
energy sector is extremely supply chain
focused. Any gain within the supply chain
demonstrates a major attribute for any innovation. Finally, technical performance
improvement linked with easier series
builds is primary when compared against
improved intrinsic individual material
performance. In addition, the adoption of
the technologies seems to have an initial
five-year cycle during the innovation introduction period, followed by a five-year
adoption period where it displaces the
previous technology.

47
http://www.structeam-ltd.com
Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #116 - October 2017
