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Performance and expectations
The DuoGen was specifically designed to maximise zero carbon electricity generation on
cruising yachts. The DuoGen’s unique wind/water capability works best where yachts are
making frequent or long sea passages, interspersed with periods at anchor or in
harbour.
The DuoGen should perform in line with the values given in our published output graphs.
However, when monitoring the system, there are external factors that can effect
performance, and may lead you to falsely conclude that there is a problem. To assist in
accurate evaluation, particularly in relation to wind mode, be aware of the following:
when monitoring the wind mode,
wind speed measurement should be made at
the height of the turbine rotor
. Where a mast head anemometer is used, there
will be significant wind shear, and it is not unusual for wind speed measurements
at turbine level to be 5 - 6 knots lower than the masthead. This is particularly true
in harbours and marinas.
when measuring performance,
battery state is also important.
Fully charged
batteries do not readily accept current, and where a charge regulator is fitted, any
dumped power will not be registered by the ship’s battery monitor. In addition,
where batteries are fully charged, or the regulator is ‘dumping’, the load seen by
the DuoGen’s alternator changes. This makes the alternator ‘stiffer’ to turn, which
in turn increases the force which furls the turbine. The increased furling angle
reduces the intercept area of the DuoGen’s air rotor which in turn lowers the
electrical output.
When evaluating the DuoGen’s air mode, try to ensure batteries are 30 - 40%
discharged, or alternatively switch on numerous loads in order to pull the
battery voltage down.
if wind mode outputs remain below expectations, first suspect
turbulence in the
wind stream
. Turbulence at a given site can be specific to a particular wind
direction where it is caused by an obstruction either up or downwind of the turbine.
When the wind direction changes, and the obstruction is no longer in line with the
turbine, outputs may return to expected levels.
if poor output cannot be attributed to site conditions,
re-check the whole
installation
against the wiring diagram and also look for poor or loose
connections. Also, check fuses and fuse holders.
finally,
ensure that the batteries are in good condition
and of sufficient
capacity. We recommend a minimum of 300 Ah for use with the DuoGen.
If you still suspect a problem with the machine, consider the following:
do the air blades spin freely? The air rotor should spin without any undue noise
or friction. If not, is there a braking switch engaged or could there be another
short circuit in the output cables? (Make sure you disconnect the batteries before
trying to find out!)
is the DuoGen free to move about its yaw axis? It should move easily with no
undue noise or friction.
If in doubt, refer to your dealer or the manufacturer.
Note that there is a short period of ‘running in’ with a new wind turbine. The bearings
and shaft seals of a new machine take 40 – 50 hours of operation before mechanical
friction falls to its design level. As a result, your DuoGen may seem a little slow to
respond in light winds until this ‘running in’ period has passed.
