If you have more power needs than a 100-watt solar panel can provide, but still need a compact unit,is a great option because it’s able to provide twice the charging power in a single panel.
When reviewing available products, we found that most solar panels for boats are around 100 watts. These panels are generally close to three feet long and nearly two feet wide, making them small enough to fit on many parts of a boat. Larger and smaller panels were considered for their unique applications as well.
That being said, panels with more efficient solar cells pack more productivity into a smaller space. So, a 100-watt solar panel with less efficient solar cells could actually be the same physical size as a 200-watt panel with the most efficient solar cells.Another key concern is whether you want a rigid solar panel or a flexible solar panel. Rigid panels are generally more efficient and well-suited for mounting on larger boats with flatter surfaces.
The hardware used to mount flexible solar panels can be more minimalistic than for rigid solar panels. In some places, they can simply be glued to the hull of the boat. While flexible panels are encased in plastics to make them more impact-resistant, the plastic material can degrade due to salt and other weather conditions.
Thin-film photovoltaic cells use semiconductors like gallium arsenide or cadmium telluride. These solar panels are generally cheaper to manufacture and are lighter and easier to mount in flexible substrates. They also contain materials that can be more hazardous and difficult to recycle at their end-of-life.
Depending on the type of boat, placing them high enough above the deck may also help reduce the amount of water and brine they get hit with, and help to reduce corrosion — particularly in salt water.Connecting solar panels directly to a battery can overcharge it, and possibly lead to failure or even explosion. Integrated this way, they can also drain the battery at night.