What they do. There are several applications for solar energy on boats. Boats that a re kept on moorings need to keep their batteries topped off, and don't have access to shore power. Cruising boats may want to augment charging options.
Panels can reduce engine operating time, or serve as an emergency backup.
Boats without auxiliary engines may use solar power for all onboard uses. How they work. Energy from the sun's light strikes the solar panel crystals and manages to knock some electrons loose which creates electricity. OK, that is a little brief, but to the point. Each solar cell in a panel creates a potential of about 0.4 volts.