Cum leg un bec la un panou solar

Current at 0.5 V ≥6.70 A

Deci ai 0,5 V, trebuie sa inseriezi mai multe...Ca nu ai ce face cu doar 0,5 V, nici sa-i ridici nu poti. De-ai avea macar 6 V ar fi super :D

...am de gind sá-mi cumpar un panou solar si sá leg de el un bec.
panoul solar arata asa  : http://www.q-cells.d...L_300704_de.pdf

FROM CELLS TO MODULES
The voltage output from a single crystalline silicon solar cell is about 0.5 V. Current is directly proportional to the cell's surface area, and designers count on about 7-A maximum output for a 6-in.2 multicrystalline cell. The typical panel module has 30 to 36 cells that are wired in series to generate a nominal 12-V output, which is actually about 17 V at peak power.

Because the cells are connected in series, and cells that are partially or completely shaded by tree branches, chimneys, or even guy wires have a high internal resistance, shading is a problem for photovoltaic modules. If even one full cell is completely shaded, the output voltage of the array will drop to half of its unshaded value to protect itself. If it didn't, the cell would be destroyed by the need to carry the current produced by the rest of the array while in its high-resistance state. If enough cells are shaded by nearby objects that throw hard-edge shadows, the whole module will drop out.

To deal with the shading problem, some modules place bypass diodes across each cell to carry the current when the cells themselves cannot. Otherwise, they would dissipate power from the unshaded cells. A separate blocking diode in each array in a parallel configuration of modules could isolate that panel if it becomes severely shaded. It would prevent other panels' current from flowing through it and being turned into heat.

Shading Effects on Photovoltaic Modules

If all the cells in a module were identical, the resultant I-V curve would be very easy to determine by summing the voltages for serial connected cells and summing the currents for parallel connected cells. Under real situations, if the cells are slightly different from each other or are not uniformly illuminated, the resultant behavior is not easily predictable anymore and depends on a complex combination of the actual electrical behavior of each cell. Several papers presented mathematical models in order to calculate the effect of non identical cells in a module  and the causes of distorted characteristic curves are well known. In this section will be discussed some particularities that occur when photovoltaic modules are partially shaded and how different bypass diodes arrangements affect the I V curves of modules in such conditions, from an experimental point of view.

Most photovoltaic modules comes with bypass diodes connected according to Fig. 8, with the purpose of protecting the module from high reverse voltages that could produce hot spots and consequent deterioration of the module. In addition to this, the diodes help to avoid a significant decrease of the curve factor when the module is a partially shaded. With interlaced diodes, the maximum reverse voltage is approximately 1/3 of the voltage of the module plus 1.4 V and with non-interlaced diodes is about 1.4 V.
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Modules with 30 or 33 cells (three columns of cells connected in series) normally have interlaced bypass diodes, while modules with 36 cells (four columns of cells connected in series) present non interlaced diodes. In these modules voltages of 12 V or 6 V are available. In modules with interlaced bypass diodes only one voltage, usually 12 V, is available.