Garden hose effect

Solar modules are usually not connected individually, but as a so-called string in series. The reason for this is that the typically required mains voltage of 230 V is easier to achieve. Solar cells have a very low voltage of approx. 0.5 V. Several solar cells are installed on a solar module and also connected in series. The voltage thus adds up. With standard 60 cells, this results in a voltage of approx. 30 V per module.
If parts of a module (solar cells) or several modules are shaded, they may prevent the flow of current due to their lower output. They simply conduct less energy. This is often referred to as the garden hose effect: Cells and modules connected in series all become less effective, as if you were squeezing or kinking a garden hose. This is why it is important to carry out a shading analysis in the planning phase.