At Carbon Concepts we
have been interested in renewable and sustainable energy for several
years. Since the technical requirements of the wind turbine
and its associated systems are a very close match to the technology
that we have already evolved in other sectors, we decided to develop
a competitive wind generator rated at 2.5 kw at a the industry
standard wind speed of 12 m/s (force 5).
SMALL SCALE WIND AND
Carbon Concepts 2.5
KW wind turbine generating set
here to see short video
|WHY A VERTICAL AXIS
vertical axis turbine offers two major advantages over the more
conventional axial configuration:
disadvantages are that the engineering is more complicated, it is
very intolerant of poor aerodynamics and the blade stresses are
higher. We believe that the advantages are critical to the
acceptability of small wind turbines, particularly when mounted on
or close to buildings. This is of particular importance
for urban installations where local authorities are seeking to meet
current energy targets.
first wind turbine has now completed its initial performance
evaluation. It is currently undergoing endurance and
structural testing while the final control system is optimised.
prototype turbine has been on test for two years, and has shown a
very high degree of mechanical reliability. The generator has been
100% reliable. We
are now very close to a production machine and would be happy to
discuss your requirements and interest.
The performance and cost
effectiveness of the wind turbine derive from the advanced technology
generator and the aerodynamics and structure of the rotor
set. The rotor has been designed in accordance with the best
available low speed aerodynamic technology and is fully optimised for
the unusual conditions of the vertical axis wind turbine. The
turbine currently drives an electrical generator, but would equally
support water or hydraulic pumps and heat pumps.
The advance tip
technology improves efficiency and minimises noise. Testing has confirmed
that, even at high speed and load, the rotor is effectively silent.
Attempts to measure the noise of the rotor showed that perceived noise
was dominated by the wind and adjacent trees.
generator set - fixed installation
DESIGN AND COMPONENT INTEGRATION
The design of the first installation
was completed in conjunction with the University of
Nottingham. The work was carried out as a fourth year Group
Development Project by four students completing their M. Eng.
degree. The design brief was that the installation should be
fully portable. It can be erected by two people without the
need for special tooling or lifting equipment and is transported on
a small boat trailer.
We believe that
the complete portability of this turbine makes it unique.
maximum stability, the generator is mounted at the bottom of the
tower and is driven by a shaft. Both electrical and mechanical
breaking systems are employed to allow a controlled emergency stop.
This turbine is set up as an electrical generator. With
appropriate processing it is suitable for battery charging, mains
connection and direct heating.
For fixed installations the same
generator and rotor will be mounted as an integrated unit at the top of the tower
(typically 5 metres). This installation is illustrated on the
left. The low weight of our
assembly means that this can also be assembled and erected on site
without special equipment or lifting gear.
The design and
development programme has been supported by a programme of modelling,
simulation and wind tunnel testing. This has given us
invaluable data, particularly in support of the self starting
behaviour of the turbine.
The photograph on the
right shows the quarter scale model mounted in the wind tunnel at
Durham University. In addition to the starting performance, it
is being used to derive the power coefficient characteristics.
This is particularly difficult on the full size turbine due to the
variability of "real" wind.
The 25% model in
the wind tunnel at Durham
note the alternative
rectangular blade form
In addition to the 2.5
kw wind turbine that we have been testing over the past two
years, we wre actively working on two new turbines.
1) 1.5 kw wind
turbine. We have already run the current blade design on
the smaller, 1.5 kw generator.
2) 5 kw wind
turbine. Following the very successful testing of the 5 kw
generator, we have started to work on a blade set to match.
This will be of a slightly different design due to the different
structural considerations of the larger machine.
here to return to Carbon Concepts home page click
here to return to Carbon Concepts products page