L
Load:
Any electrical component that consumes
electric power. This will depend on each system
and varies during the day in accordance with
the way in which the system works.
Load controller:
A component in the photovoltaic
system which regulates battery charging.
M
Maximum power current:
Current corresponding
to the maximum power point.
Maximum power point:
Point on the I-V curve
where the product of I x V (power) has its maximum
value (the top of the curve).
Maximum power voltage:
Voltage corresponding
to the maximum power point.
Module or solar photovoltaic module:
A group of
interconnected solar cells within a sealed unit.
N
Nominal power:
Power according to the specifications
or nameplate of a generating unit.
O
Open circuit voltage:
Voltage measured at the terminals
in a photovoltaic system at zero current.
Orientation (Azimuth):
Angle of orientation of the
surface of a panel in relation to the solar south.
The geographical south (or true solar south) should
not be confused with the magnetic south, which
is shown by a compass, although in Spain the
difference between the two is not very significant.
P
Parallel connection:
Connection method in
which all the positive terminals of a module are
connected together at one point in the circuit and
all the negative terminals are connected together at
another point. If the modules in the circuit are all
the same, the total circuit current is equal to the
sum of the individual module currents. The voltage
is equal across all modules in the circuit.
Peak sun hours:
Hours in which the solar irradiance
reaches an average of 1 kWh/sq. m..
Performance:
The relationship between the energy
which is really converted into useful energy and that
which a certain device needs to function.
Pitch:
The angle between the photovoltaic panel
and a perfectly horizontal or level surface.
S
Series connection (String):
Connection method in
which the positive terminal of a module is connected
to the negative terminal of the next module and so
on. If the modules are all the same, the voltage
across the circuit is the sum of the individual voltage
drops across each module and the current that
flows through the modules is the same.
Short circuit:
An unintended connection between
two conductors of different phases or a connection
between these and a neutral conductor.
Short circuit current:
Current which is measured
at the terminals of a module when a short circuit
occurs.
Solar array:
A group of solar photovoltaic modules
installed and electrically connected.
Solar cell or photovoltaic cell:
A device which
converts sunlight (photons) into electricity. It is the
fundamental element in solar photovoltaic panels.
Solar radiation:
Amount of energy from the sun
which reaches a surface in a certain period of time.
Solar Tile :
A Tile with photovoltaic properties
and characteristics.
In addition to generating
clean and renewable energy, it is an element which
integrates completely into the outer layer of the
roof, ensuring the watertightness of the roof and
contributing aesthetic value.
Standard test conditions (STC):
Conditions
under which photovoltaic modules are tested
in the laboratory (1 kWh/sq. m. solar radiation,
cell temperature at 25°C and solar spectrum
corresponding to an air mass of 1,5).
String:
See Series connection.
Switch:
Device used to connect or disconnect part
of an electrical installation.
W
Wp (Watt peak):
Unit of measurement for a solar
photovoltaic module which denotes the maximum
power the module can generate under standard
operating conditions (1.000 W/sq. m., 25°C and air
mass of 1,5).
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