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| − | {| style="width: 564px; height: 294px" cellspacing="0" cellpadding="0" border="1" | + | <br> |
| | + | |
| | + | {| cellspacing="0" cellpadding="0" width="587" border="1" |
| | |- | | |- |
| − | | valign="top" width="205" | | + | | valign="top" width="114" | |
| − | '''<span>Cell material</span>''' | + | '''Cell material''' |
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| − | | valign="top" width="143" | | + | | valign="top" width="71" | |
| − | '''<span>Module efficiency</span>''' | + | '''Module efficiency''' |
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| − | | valign="top" width="267" | | + | | valign="top" width="81" | |
| − | '''<span>Surface area needed for 1 kW<sub>p</sub></span>''' | + | '''Surface area needed for 1 kW<sub>p</sub>''' |
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| − | | valign="top" width="267" | | + | | valign="top" width="169" | |
| | '''Advantages''' | | '''Advantages''' |
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| − | | valign="top" width="267" | | + | | valign="top" width="151" | |
| | '''Disadvantages''' | | '''Disadvantages''' |
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| | |- | | |- |
| − | | valign="top" width="205" | | + | | valign="top" width="114" | |
| − | <span>Monocrystalline silicon</span>
| + | Monocrystalline silicon |
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| − | | valign="top" width="143" | | + | | valign="top" width="71" | |
| − | <span>15-18 %</span>
| + | 15-18 % |
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| − | | valign="top" width="267" | | + | | valign="top" width="81" | |
| − | <span>7-9 m²</span>
| + | 7-9 m² |
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| − | | valign="top" width="267" | | + | | valign="top" width="169" | |
| | - most efficient PV modules | | - most efficient PV modules |
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| − | | valign="top" width="267" | | + | | valign="top" width="151" | |
| − | - most expensive PV modules | + | - most expensive - waste of silicon in the production process |
| − | | + | |
| − | - waste of silicon in the production process | + | |
| | | | |
| | |- | | |- |
| − | | valign="top" width="205" | | + | | valign="top" width="114" | |
| − | <span>Polycrystalline silicon</span>
| + | Polycrystalline silicon |
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| − | | valign="top" width="143" | | + | | valign="top" width="71" | |
| − | <span>13-16 %</span>
| + | 13-16 % |
| | | | |
| − | | valign="top" width="267" | | + | | valign="top" width="81" | |
| − | <span>8-9 m²</span>
| + | 8-9 m² |
| | + | |
| | + | | valign="top" width="169" | |
| | + | - less energy and time needed for production than for monocrystalline cells (= lower costs) |
| | + | |
| | + | | valign="top" width="151" | |
| | + | - slightly less efficient |
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| − | | valign="top" width="267" | -
| |
| − | | valign="top" width="267" | -
| |
| | |- | | |- |
| − | | valign="top" width="205" | | + | | valign="top" width="114" | |
| − | <span>Micromorph tandem (aµ-Si)</span>
| + | Micromorph tandem (aµ-Si) |
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| − | | valign="top" width="143" | | + | | valign="top" width="71" | |
| − | <span>6-9 %</span>
| + | 6-9 % |
| | | | |
| − | | valign="top" width="267" | | + | | valign="top" width="81" | |
| − | <span>9-12 m²</span>
| + | 9-12 m² |
| | + | |
| | + | | valign="top" width="169" | |
| | + | - |
| | + | |
| | + | | valign="top" width="151" | |
| | + | - more space for the same output needed |
| | | | |
| − | | valign="top" width="267" | -
| |
| − | | valign="top" width="267" | -
| |
| | |- | | |- |
| − | | valign="top" width="205" | | + | | valign="top" width="114" | |
| − | <span>Thin film:</span>
| + | Thin film: |
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| − | <span>Copper indium diselenide (CIS)</span>
| + | Copper indium diselenide (CIS) |
| | | | |
| − | | valign="top" width="143" | | + | | valign="top" width="71" | |
| − | <span>10-12 %</span>
| + | 10-12 % |
| | | | |
| − | | valign="top" width="267" | | + | | valign="top" width="81" | |
| − | <span>9-11 m²</span>
| + | 9-11 m² |
| | + | |
| | + | | valign="top" width="169" | |
| | + | - higher temperatures and shadows have lower impact on performance |
| | + | |
| | + | - lower production costs |
| | + | |
| | + | | valign="top" width="151" | |
| | + | - more space for the same output needed |
| | | | |
| − | | valign="top" width="267" | - higher temperatures and shadows have lower impact on performance
| |
| − | | valign="top" width="267" | -
| |
| | |- | | |- |
| − | | valign="top" width="205" | | + | | valign="top" width="114" | |
| − | <span>Thin film:</span>
| + | Thin film: Cadmium telluride (CdTe) |
| | | | |
| − | Cadmium telluride (CdTe),
| + | | valign="top" width="71" | |
| | + | 9-11 % |
| | | | |
| − | | valign="top" width="143" | | + | | valign="top" width="81" | |
| − | <span>9-11 %</span>
| + | 11-13 m² |
| | | | |
| − | | valign="top" width="267" | | + | | valign="top" width="169" | |
| − | <span>11-13 m²</span>
| + | - higher temperatures and shadows have lower impact on performance |
| | | | |
| − | | valign="top" width="267" |
| + | - highest cost-cutting potential |
| − | - higher temperatures and shadows have lower impact on performance | + | |
| | | | |
| − | - high cost-cutting potential | + | | valign="top" width="151" | |
| | + | - more space for the same output needed |
| | | | |
| − | | valign="top" width="267" |
| |
| | |- | | |- |
| − | | valign="top" width="205" | | + | | valign="top" width="114" | |
| − | <span>Amorphus silicon (a-Si)</span>
| + | Amorphus silicon (a-Si) |
| | + | |
| | + | | valign="top" width="71" | |
| | + | 6-8 % |
| | + | |
| | + | | valign="top" width="81" | |
| | + | 13-20 m² |
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| − | | valign="top" width="143" | | + | | valign="top" width="169" | |
| − | <span>6-8 %</span>
| + | - less silicon needed |
| | | | |
| − | | valign="top" width="267" | | + | | valign="top" width="151" | |
| − | <span>13-20 m²</span>
| + | - more space for the same output needed |
| | | | |
| − | | valign="top" width="267" | - less silicon needed
| |
| − | | valign="top" width="267" |
| |
| | |} | | |} |
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| | <br> | | <br> |
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| − | Partly taken from: Solarpraxis (Hrsg.): Photovoltaik für Profis. Verkauf, Planung Montage von Solarstromanlagen, 2., vollständig überabeitete Auflage, 2009, S. 133.<br> | + | Partly taken from: Solarpraxis (Hrsg.): Photovoltaik für Profis. Verkauf, Planung Montage von Solarstromanlagen, 2., vollständig überabeitete Auflage, 2009, S. 131-135.<br> |
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| | <br> | | <br> |
Monocrystalline silicon PV cells are made from silicon wafers that are cut from cylindrical single-crystal silicon ingots. To form nearly quadratic cells, that can be easily integrated in one module, the rotund cells have to be cut. Thus, refined silicon is wasted in the cell production process. Monocrystalline silicon shows predictable and uniform behaviour but due to the careful and slow manufacturing processes required, it is also the most expensive type of silicon.
Modules consisting of monocrystalline silicon PV cells reach commercial efficiencies between 15 % and 18 %. So far, they are the most efficient modules and have the largest market share.
Polycrystalline or multicrystalline silicon PV cells are made from cast square ingots - large blocks of molten silicon, carefully cooled and solidified. They are less expensive to produce than monocrystalline silicon PV cells, but are marginally less efficient, with module conversion efficiencies between 13 and 16 %.
The various thin film technologies currently being developed reduce the amount (or mass) of light absorbing material required in creating a solar cell. This can lead to reduced processing costs from that of bulk materials (in the case of silicon thin films) but also tends to reduce energy conversion efficiency (an average 6 to 12 % module efficiency),
Thin film PV cells are constructed by depositing extremely thin layers of photovoltaic semi-conductor materials onto a backing material such as glass, stainless steel or plastic. Thin film materials commercially used are amorphous silicon (a-Si), cadmium telluride (CdTe), and copper-indium-(gallium)-diselenide (CI(G)S).
For almost all applications, the one-half volt produced by a single cell is inadequate. Therefore, cells are connected together in series to increase the voltage. Several of these series strings of cells may be connected together in parallel to increase the current as well.
Therefore, the interconnected cells and their electrical connections are sandwiched between a top layer of glass or clear plastic and a lower level of plastic or plastic and metal. An outer frame is attached to increase mechanical strength, and to provide a way to mount the unit. This package is called a "module" or "panel". Typically, a module is the basic building block of photovoltaic systems
The peak power output of a solar module depends on the number of cells connected and their size. Module performance is generally rated under Standard Test Conditions (STC) : irradiance of 1,000 W/m², solar spectrum of AM 1.5 and module temperature at 25°C. Solar modules are rated in peak watts [Wp] according to their output under STC. Thus, a 50 Wp module can be expected to supply 50 W of power under optimal conditions. The performance is reduced by high temperatures.
Modules can be connected in series and/or in parallel depending on the system requirements. A serial connection increases the voltage, a parallel connection increases the current.
Partly taken from: Solarpraxis (Hrsg.): Photovoltaik für Profis. Verkauf, Planung Montage von Solarstromanlagen, 2., vollständig überabeitete Auflage, 2009, S. 131-135.
