SMA SB 2800i - Manual (Page 46)

Glossary Operating Instructions
44 SMA Regelsysteme GmbH SB2800i-11:FE0504
Technical facility to convert light energy into electrical energy. Usually the term includes all PV
modules of a PV plant that have been mounted and electrically wired.
PV module
See „ Solar module“
Solar energy
Energy supplied by the sun, i. E. energy from sunlight or other insolation (heat, UV radiation)
Solar module
Combination of individual solar cells in one enclosure which protects the delicate cells against
mechanical strain and guarantees easy installation.
Solar cell
Electronic component which can supply electrical energy when in sunlight. As the electric voltage
of one single solar cell is very low (approx. 0.5 V) several cells are combined into solar modules.
The material mostly used for solar cells at the moment is silicon. It is upgraded in different ways
(mono-crystaline, poly-crystaline, amorph) before use. There are also various ways to increase
efficiency mechanically. In addition totally new materials are currently tested (Cadmium-Tellurid,
Cadmium-Indium-sulfide, titan dioxide etc.).
String
A group of solar modules switched in series. Usually a PV plant consists of several strings. Thus it
is possible to avoid too high yield losses if the modules are shadowed to a different extent.
String inverter
Inverter concept avoiding the disadvantages of a concept with one central inverter. The PV
generator is divided into individual strings which are each connected to the external grid with
their own string inverter. This considerably simplifies installation and reduces yield losses due to
variations in manufacture or a different degree of shading of solar modules.
Inverter
Device to convert the direct current (DC) supplied by the PV generator into alternating current (AC)
which is required for the supply of most consumers and especially for feeding into the public grid.
Inverters for PV plants usually include one or more MPP trackers.
Central inverter
Inverter concept where all PV modules are wired among each other (switching in series and / or
in parallel). One single inverter feeds into the external grid. Costs for a central inverter concept
are lower, but installation might be much more complicated and yield losses may occur due to
shadowing of individual solar modules.