Solar modules series-connection

Photovoltaic systems for specific applications are produced by connecting individual modules in series and parallel to provide the desired voltage and current (Figure 4). Each module is constructed of individual solar cells also connected in series and parallel. Modules are typically available in ratings from a few peak watts to 250 peak watts. 

A necessary prerequisite for high module efficiencies is the uniform distribution of material and cell properties on the substrate to avoid power losses due to averaging effects. The total area of solar modules is divided into cell strips, which are interconnected by a sequence of deposition and cutting steps. Figure 8.11 illustrates the structure for series-connection in thin film silicon... 

Fig. 8.11. Monolithic series-connection of silicon thin film solar modules by a sequence of deposition and laser scribing steps. The current flow is indicated by the dotted arrow. For calculation of resistive and optical losses the active cell width ioa and dead area width Wd are needed...

The aperture area of a solar module is defined by the inner boundary of total laser scribed area. For every kind of series-connection, the active solar cell area is reduced by the area of the interconnection structure. Area losses increase if the cell width is reduced. On the other hand, electrical losses in contact layers become more severe with increasing cell width due to increasing cell current. Hence, optimization of the cell width must consider both area losses (dead area) due to patterning and series resistance losses due to TCO sheet resistance. These power losses can be described by the loss factors /, which is the sum of the loss factors /d (area losses) and /tco (resistive losses in front TCO) [69] ... 

Solar Module (Panel) - A solar photovoltaic device that produces a specified power output under defined test conditions, usually composed of groups of solar cells connected In series, in parallel, or In series-parallel combinations. 

Biancardo and co-workers assembled a semitransparent quasi-solid state dye-sensitized solar module connecting in series solar cells assembled with a gel electrolyte. Each individual cell presented an efficiency of 1% under 100 mW cm" . The efficiency of the whole module composed 23 cells (active area of 625 cm ) reached 0.3%. The authors claimed that, although the efficiency was higher for modules assembled with liquid electrolytes, the use of the gel electrolyte clearly improved the performance of the cells after 1 month, leading to devices with extended lifetime. ... 

Figure 10.23 shows a picture of two modules composed of 16 solar cells each connected in series, assembled in the LPCR, at the University of Campinas-UNICAMP, in Campinas, BrazU. The modules were irradiated with a commercial fluorescent lamp of 50 W, positioned 40 cm from the module. Using this light source, which is very diffuse (irradiation of 10 W m" ), the module presented Kc = 7.8 V. Under direct solar radiation, the same module presented /sc = 8.5 mA and Uoc = 10.6 V at 800 W m" , and /sc = 2.5 mA and Kc = 9.6 V at 100 W m . 

Variation of the maximum generated power produced by a solar module assembled with 13 series connected DSSC during one day of outdoor exposure. 

The research effort in many laboratories around the world on the optimization of laboratory-scale (1-cm- area) cells has led to the development of large-area (1 m ) solar cell modules with an efficiency exceeding 10% [613,614]. In a module individual cells can be connected in series or parallel, depending on the desired... 

Connecting two or more cells to each other creates a string. A string is a row of cells connected to each other in either series or parallel. Multiple strings are then connected to each other in series or parallel to form the whole of the solar panel or module. 

Ail the experiments shown in this papa were carried out under sunlight in CPCs at the Plataforma Solar de Almeria (PSA, latitude 37, longitude 2.4 W). The pilot plants (17) are made up of different solar collectors, tanks and pumps. Each collector (see Fig. 3c) consists of Pyrex tubes (installed in the axis of the CPC) connected in series and mounted on a fixed platform tilted 37 (local latitude). The water flows directly from one module to another and finally into a tank. The total volume (Vt) of the reactor is separated in total irradiated volume... 

The photovoltaic array is nothing but modules connected in series and parallel. The PV array for the SRFCs consists of several modules, which in turn consist of solar cells. The solar cells used in designing the present PV array are crystalline Si solar cells. The appropriate cell details are given in the Table 12.2. 

But, during the day, the solar irradiation from the sun is not at a constant wattage of 1000 W/m. It varies from a minimum to a maximum. The solar irradiation or the flux for any given day is like a positive sine curve. For the Simulink model, the flux is the input and the output is the power produced by an array. Just changing the number of cells or modules that are connected in series or parallel can alter this power. 

Although the water lens could not condense solar light homogeneously, the thermal nonuniformity at the insulator surface was immediately diffused and did not affect the TE-generation performance. As an example, a power output of approximately 70 mW could be achieved using a 0.2-m-wide water lens when perpendicular light was condensed on a 2.5-mm-wide module connected to six pairs of TE elements in series. 

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