If you are not using an electronics system it is critically important to consider the motor
and panel in conjunction with each other to ensure the best voltage and current match
from panel to motor in order to obtain optimum performance. As Sun level varies you
will need to make adjustments to maintain the motor and panel match.
SEE SECTION 8 ELECTRONICS for a detailed description.
Some factors to consider when making your decision on which solar panel to use on your
car are:
* Voltage, Current and consequently the Power you require.* Can you obtain a commercial panel to suit your requirements?* Should you manufacture a panel from commercial cells that are already mounted
on a backing and protected by encapsulation?
(such as the cells available from Dick Smith Scorpio , Engelec and others)* Should you manufacture a panel from un-mounted cells cut to suit you
requirements
(Caution: un-mounted cells are brittle, require careful handling are extremely
difficult to solder to and must be mounted on a stiff backing to prevent breakage.
They may require some protective covering.)- Weight of your panel
Is the panel heavier than the panel plus ballast weight required by the
regulations, resulting in a weight handicap?
Effect of panel & ballast weight and centre of gravity on car stability.
Maximum power is developed from a panel when light strikes it at right angles. This is
virtually impossible to achieve on a model solar car, as the position of the Sun relative to
the car changes as the car traverses the track.
Shading even one element on a panel will drop the output significantly. Take care when
mounting your panel to avoid shading and remember to keep the panel clean.
Solar panel power output falls as the panel temperature increases so do not leave your
panel laying around in the sun cooking, some competitors cool their panels prior to
racing. With panel power dropping by about 0.5% per degree C temperature rise, a 25
degree C temperature reduction results in a worthwhile power increase. Be cautious the
panel will heat quickly to a quite high temperature when placed in the sun. (we have
measured panel temperature of 60 deg. C after ½ hour on a cloudless day of 20 deg C )
B: Ballast & your Solar Panel
To ensure a fair competition the power output of all solar panels is measured then based
on this measured power the minimum weight of ballast plus solar panel required by the