aleo
aleo solar Deutschland GmbH
| Osterstraße 15| 26122 Oldenburg | Germany | [email protected]
installation instructions Edition 01/2012 en-GB-Intl (120508b)
Page 11/60
5.2.1.
Special requirements
If you have any special requirements for your system (e.g. an
island system) or if there are any special circumstances at
the intended location, a different alignment may merit
consideration.
These special requirements may include:
a specific desired main usage phase
an especially clear view of the sun's path at the
location
For example: if the desired daily main usage phase of a
system in the northern hemisphere is during the evening and
if the location has a particularly clear view of the sun's path to
the south-west, then a southwest alignment may be more
advantageous.
5.3.
Inclination (elevation)
5.3.1.
Minimum inclination
Incline the surfaces of the solar modules at an angle at
least 10° from horizontal so that precipitation can run off and
therefore facilitates the self-cleaning of the modules.
For optimal self-cleaning, we recommend an inclination angle
of at least 15° from horizontal.
5.3.2.
Optimum inclination
The optimum inclination angle for power output is particularly
dependent on the latitude at the location and the desired
main usage phase for the photovoltaic system.
Typical inclination angle values for Europe are around 20° in
Southern Europe, around 30° in Central Europe, and
around 40° in Northern Europe.
The following formula can be used to estimate the optimum
inclination:
Horizontal angle = latitude at the location - 20°
More exact values for a chosen location can be taken from
corresponding tables or a suitable calculation programme.
5.3.3.
Tracking installation
If you would like to use an automatic tracking system, please
observe the guidelines and requirements of the tracking
system manufacturer.
An automatic tracking system can ensure higher yields,
particularly in summer, but it also entails substantially higher
installation and maintenance costs.
5.4.
Avoidance of shadowing
NOTICE
Avoid shadowing of the solar modules. In particular,
this also applies to small-scale shadowing from
small nearby objects such as antennas or lightning
protection systems.
If there is systematic shadowing over the course of
the day or year at the location due to neighbouring
objects and there is no way of changing this
shadowing then
consider a different location
–OR–
only plan to use the non-shadowed area at the
location for your photovoltaic generator.
5.4.1.
Effects of shadowing
Even the shadowing of a single module or a single solar cell
can have a noticeable effect on the performance of the entire
photovoltaic system.
If shadows fall on individual solar modules of a photovoltaic
generator or on individual solar cells of a solar module, the
shadowed parts generate less or even no further electrical
output. This can have an effect on the yield of an entire
module string and, subsequently, the whole generator.
Shadowing also often means that a portion of the electrical
output created in the module no longer contributes toward
the yield because it is consumed by the solar cells in the
shadowed area instead. This can cause a rise in the tempe-
rature of the shadowed cells compared to the normally lit
cells. In extreme cases, this can create a fire risk.
Extended or systematic shadowing can cause significant yield
losses. Furthermore, over the long run, this can lead to
accelerated aging and therefore output losses or even failure
of the photovoltaic generator. Consequently, such shadowing
dependent on the time of day or year (particularly in winter)
caused by parts of buildings, for example, should be avoided
in order to optimise the yield and service life of your system.
More details regarding avoidance of shadowing can be found
in Appendix B, 'Creation and Avoidance of Shadowing'.
5.4.2.
Protective devices within the modules
aleo modules are equipped with bypass elements that, in the
case of shadowing, ensure that increased temperatures
caused by internal power consumption remain at uncritical
levels, thereby protecting the module. Systematic shadowing
should also be avoided as these bypass elements should not
be subjected to regular, longer-lasting loads.
