56 MAY / JUNE 2022 popularmechanics.co.za
1INNOVATION
THE PROBLEM
The larger the wind turbine, the greater
the forces enacted on the entire structure
- this is an inherent issue with large wind
turbines. Aero forces are created from all
wings, including wind-turbine blades; this
is what allows them to generate power
from the wind. However, these shapes
also create forces beyond what is required
to generate power, resulting in excess
loadings during operation and massive
loadings during storm events.
These maximum loadings are what
entire wind turbine structures are
designed around, ultimately impacting
material costs, turbine size and energy
outputs. Larger turbines are better turbines
due to the non-linear way in which wind
power scales – a blade length increase of
two times results in a threefold output
increase. As a result of this, wind turbines
have been getting bigger, with the largest
offshore units sporting blades of up to
116 m in length.
Due to the limiting factors of loadings,
size and reliability are limited too. As a
result, turbine manufacturers are actively
seeking load mitigation solutions that
can bring down extreme loads, while
maintaining the power outputs of
the turbines.- One of the main factors
limiting the size of turbine
blades is the logistics
around transporting them
- they are often more than
100 m in length.
- Brayfoil’s patented
technology allows for the
morphing of a blade to suit
prevailing conditions, the
desired outputs, or both. - The design of Brayfoil’s
blade is inspired by the
dynamic nature of the
wings of a bird of prey.
- One of the main factors
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