Two main reasons why solar panels are almost never connected in series only are:
- Voltage Addition and Safety Concerns: Connecting solar panels in series adds their voltages, which can result in very high overall voltage. This high voltage can exceed the safe operating limits of the system components and create safety hazards during installation and maintenance.
- Vulnerability to Single Panel Issues: In a series connection, if one panel is shaded, damaged, or underperforms, it limits the current and thereby reduces the output of the entire string. This makes the series-only system less reliable and prone to significant power loss if any single panel fails or is compromised.
These factors often lead to solar panel installations using a combination of series and parallel connections to balance voltage, current, safety, and reliability.
