I have a total of 150 watts mounted on my transom cover, companionway
, and companionway hatch
cover. I used a combination of 12 watt and 25 watt panels. You can see the panels mounted on my transom cover on the Aurinco site here: Compact 25W module
. Since the panels are so thin and tolerate being bent over a little camber, the mounting on the companionway sliding hatch turned out really well and made good use of that otherwise wasted horizontal surface. The panels slide in and out of my hatch cover with no problems.
I had four 12 watt panels mounted on my foredeck but encountered water
intrusion into the panels. See photo
. The seawater intrusion would have eventually dissolved the aluminum
bonding wire seen in the photo
. The problem was caused by the terminal wires not being completely recessed into the wire channels during manufacture on the underside of the panels. I had mounted the panels flush against the deck
using fasteners. This caused the wires to abrade against the deck during normal deck flexing, eventually abrading away the clear plastic coating over the wires and allowing water
into the panels. Aurinco refunded my purchase
cost and cost of return shipping
. I also had one 12 watt panel delaminate near the mounting holes, caused by deck flexing around the holes, which also resulted in water intrusion.
I advise against mounting the panels flush against a surface where moisture can be entrapped and eventually intrude into the panels under the effects of vapor pressure and wicking. Offsetting the panels from the mounting surface even a minuscule amount will prevent vapor pressure from forcing water into the panels and also prevent abrasion of the coating over the terminal wires on the panel underside.
I recommend 3M VHB tape under the panels. The panels that I mounted with VHB tape have had no issues after 2 years. I used multiple strips of 1/2 inch wide VHB #4941 tape running the full underside length of the panels. The tape is thin (0.045"), adheres well to the aluminum backing, and provides enough of a gap to prevent abrasion of the terminal wire coating, moisture entrapment and eventual water intrusion. Its bond is also strong enough to hold the panels onto FRP, alleviating the need to use fasteners in locations where the panels aren't subjected to sheering forces (it will also make stealing them a very frustrating endeavor). The panels can still be removed later by carefully sawing the VHB tape with a thin wire or saw blade, being careful not to cut the terminal wires. That small airgap will also allow the panels to run a little cooler, improving efficiency.
If you need to use fasteners, or don't want to later deal with removing the panels adhered with VHB tape, any single-sided adhesive
thin foam tape should do in place of the VHB. Just don't mount the panels flush to a surface that will eventually abrade the underside of the terminal wire coating, and use mounting screws with shanks smaller than the mounting holes (the holes can be expanded) and washers to prevent stressing the panels around the holes.