Mounting solar panels on hand rails around a boat's perimeter allows for some flexibility of use, plus the opportunity to angle the panels if you happen to be a dedicated twiddler with too much time on your hands. But when using standard aluminum-framed glass panels, necessity dictates that the clamps that secure the panel to the rail must be on the center-line lengthwise.
Glass panels are pretty heavy, and too much twisting and torsion will either "soften up" the aluminum frame or cause the glass to crack and/or shatter. Most panels of this type are designed to be installed on solid, permanent structures like roofs (specialized marine panels like the Solara Ultra series being an exception), and it is assumed that these land-based platforms will not heave, pitch, twist, or generally rock-and-roll (barring earthquakes) like a small/medium sized boat often does.
With this in mind, having a balanced mounting point is essential when using glass panels in rail-mount applications if regularly having to replace panels is to be avoided. But having a balanced mount, i.e. with the rail clamps on the center-line lengthwise, means that half of the panel's width will be intruding into the walkway, cockpit, etc. when deployed, and the wider the panel the more it will become an obstacle to movement.
Choosing a narrow panel is one way around this dilemma. Here's one way to do it:
The Solara Ultra series 120w and 150w marine glass panels are just 21.5" wide, so that only 11" or so will be hanging over the boat, but even that will be too much for some customers with smaller vessels.
A better solution is to use durable, lightweight panels that will not suffer from twisting and flexing, are not made with glass, and that have a sturdy yet low-bulk fame.
This is a perfect application for the Solara Power M series 115w and 140w panels fitted with an EZ Mount frame. The razor-thin Power M panels are designed to be mounted on curved surfaces like decks and cabin tops, and besides being able to flex, they are also durable enough to be walked on.
Once installed in an EZ Mount frame, the Power M morphs into a lightweight, tough, aluminum-framed panel that can absorb some flexing without damage to the panel or frame. Now we have a panel to which we can safely install rail clamps onto one side lengthways, install a simple strut system, and then have practically all of the panel outboard of the boat during operation. Yes, I know what you're thinking, and a telescopic boat hook will probably do, but we'd like to see something a little more elaborate, and kudos to Mark Gilg on S/V Tarok for coming up with the snazzy arrangement seen in the photo's.
Once the panels are equipped with easily disconnected plugs and sockets (Coastal now offers an excellent range from Philippi), they can be easily removed and stowed for security or when on passage.
Thanks to their leight weight, minimal bulk, and rugged durability, Solara Power M panels with EZ Mount frames enjoy a huge advantage over glass panels when used in this type of application.