JEC COMPOSITES MAGAZINE - Issue #99 - September 2015 - 28

design

A wind turbine without blades

Vortex Bladeless, a Spanish tech startup, has developed a multipatented wind turbine without blades. The turbine design uses an
aero-elastic coupling that architects and civil engineers absolutely
want to avoid to prevent building or bridge collapse. This is the
beauty of this new concept: making the best with a phenomenon
usually considered the worst. Although there is no blade in this
concept, composites are still there.

ortex Bladeless uses a radically new
approach to capturing wind energy.
Its device captures the energy of
vorticity, an aerodynamic effect (vortex
shedding) that has plagued structural engineers and architects for ages. As the wind
blows past a fixed structure, its flow changes
and generates a cyclical pattern of vortices.
Once these forces are strong enough, the
fixed structure starts oscillating and may
enter into resonance with the lateral forces
of the wind, and even collapse. A classic
example of this phenomenon is the collapse
of the Tacoma Narrows Bridge in the USA
three months after its inauguration. Instead
of avoiding these aerodynamic instabilities,
the Vortex Bladeless technology maximizes
the resulting oscillation and captures that
energy. Here, instead of the usual tower, nacelle and blades, the device has a fixed mast,
a power generator and a hollow, lightweight
and semi-rigid fibreglass cylinder on the top.
It is known that a structure can only have a
certain frequency of oscillation, which limits
the number of working hours. However,
thanks to a self-tuning magnetic coupling
system, the Vortex can operate in a wider
range of wind speeds. This system allows
maximizing the oscillation amplitudes:
when the wind intensifies, the magnetic

force of repulsion goes up, which reduces
the distance between the rod and the
magnet. As a result, the oscillation and the
potential of generated energy increase to the
maximum.

Main advantages
According to its inventors, one of the main
advantages of the Vortex is its dramatically
low cost. In fact, the normalized cost of
energy generation (LCOE) for a typical
onshore facility is $0.035/kWh, including
capital costs, operation and maintenance,
performance, land leases, insurance and
other administrative expenses. These cost reductions come from reduced manufacturing
costs (roughly estimated by Vortex Bladeless
at around 51% of the usual wind turbine
production cost). Moreover, by having the
alternator (and the centre of gravity) close to
the ground, the Vortex simplifies assembly

operations, use and maintenance.
The design completely eliminates mechanical elements that can suffer wear and tear
from friction, leading to an estimated 53%
reduction in maintenance costs compared
to traditional wind turbines, and avoids
having to change oil or replace mechanical
parts. Computational modelling estimates
the operational lifetime of this new type of
installation to be between 32 and 96 years.
Other advantages: the impact on the bird
population is expected to be much smaller
and the impact sound level non-existent.

Available products
Vortex Bladeless has already tested dozens of
prototypes in wind tunnels and is currently
optimizing the field tests (see Figure 1).
The first Vortex products will be focused
on small-scale production with a 100W, 3
metre high and less than 10kg model followed one year later by another of 4kW, 13
m high and less than 100kg. In three years,
Vortex should be able to present a +1MW
wind generator. n
More information:
www.vortexbladeless.com

The Bladeless
technology
step-by-step
Fig.1: The demonstrator on-site

28 jec composites magazine / No99 September 2015

http://www.vortexbladeless.com

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #99 - September 2015