Solarenergy

The principle of Photovoltaic (PV) systems based on the direct conversion of sunlight into electrical energy within a solar cell. Several solar cells together form a solar module, multiple modules connected together the PV generator.

Basically, solar cells are divided into 3 types:

  • Crystalline silicon cells: module efficiencies between 10 -20%, required area for 1 kWp PV: 7-9m ²
  • Thinfilm cells: module efficiencies between 9-15%, required area for 1 kWp PV: 9-20m ²
  • Nanostructured solar cells. These are currently first in the market

In open areas or roof systems are mainly used standard modules. The Standardization has achieved the goal of minimizing costs with a maximum energy yield per square meter. A typical standard module of crystalline solar cells consist of 36-216 cells and has a capacity to 100-300 Wp The cells usually arranged in 4-8 rows next to each other, so that a rectangular module with dimensions of, for example, 1.60 x 0.80 m results.
In architecture, special modules are used frequently. These are made specifically for the intended use and not produced in series for the market.
The modules are available in series (string) or parallel connected. The PV-generator, the heart of the system, direct current is generated..

As for a power supply, but AC is needed is a another key element of a PV system the inverter, converts the DC current into AC current.

The inverter is the interface between the PV generator and the mains power or the consumer. He converts the direct current to alternating current and adjusts the frequency and the voltage level for the home network or public network. The maximum power point (MPP) of a PV array varies according to irradiation conditions more or less. To achieve on the AC side, the maximum power, he can move its operating point as accurately and as the MPP-line as closely as possible to adjust the generator. This adaptation occurs over a MPP. The accuracy of the MPP controller contributes very significantly to the amount of usable power output. This is called the tracking efficiency.

For the best overall performance of the system, both the vote of the inverter to the generator power and the wiring between the modules are of central importance.

Critical to the yield of a photovoltaic system are an optimal design, quality components, professional installation and a comprehensive quality assurance. Through this quality assurance, consisting of earnings reports, module surveying, system acceptance and long-term monitoring can ensure that the predicted yield is achieved over the life of the system!
 

Einspeisetarife in Deutschland für 20 Jahre, plus Inbetriebnahmejahr (in Cent/kWh)

Leistungsabhängige Fördersätze in €ct/kWh
Anlagentyp
2010
07/2010
10/2010
2011
2012 (bei 9% Kürzung)
2012 (bei 21% Kürzung)
2013 (bei 9% Kürzung)
2013 (bei 21% Kürzung) 
auf einem Gebäude oder einer Lärmschutzwand
bis 30 kW
39,14
34,05
33,03
28,74
26,15
22,70
23,80
17,94
30 kW bis 100 kW
37,23
32,39
31,42
27,34
24,88
21,60
22,64
17,06
ab 100 kW
35,23
30,65
29,73
25,87
23,54
20,44
21,42
16,15
ab 1000 kW
29,37
25,55
24,79
21,57
19,63
17,04
17,86
13,46
Freiflächenanlagen (leistungsunabhängig)
vorbelastete Flächen
28,43
26,16
25,37
22,07
20,08
17,43
18,27
13,77
Ackerflächen
28,43
-
-
-
-
-
 
 
Sonstige Freiflächen
28,43
25,02
24,26
21,11
19,21
16,68
17,48
13,17
Selbstverbrauchsvergütung für Anlagen auf Gebäuden
bis 30 kW bis 30% Selbstverbrauch
22,76
17,67
16,65
14,36
13,07
11,34
11,89
8,96
bis 30 kW ab 30% Selbstverbrauch
22,76
22,05
21,03
18,30
16,65
14,46
15,15
11,42
bis 100 kW bis 30% Selbstverbrauch
-
16,01
15,04
13,08
11,90
10,33
10,83
8,16
bis 100 kW ab 30% Selbstverbrauch
-
20,39
19,42
16,90
15,38
13,35
14,00
10,55
100 bis 500 kW bis 30% Selbstverbrauch
-
14,27
13,35
11,61
10,57
9,17
9,62
7,26
100 bis 500 kW ab 30% Selbstverbrauch
-
18,65
17,73
15,43
14,04
12,19
12,78
9,63

Grundlage: EEG 11/2010 (aktualisiert)