A sailboat needs some form of electrical power generation, if only to run a VHF radio and navigation lights. Portable devices need recharging regularly. While the inboard engine can provide ample power to charge batteries, it is noisy and burns fuel. Choices are limited on a boat, and other than a dedicated generator, impractical on a small boat, solar panels and wind generators usually provide the required electrical power. Wind generators are quite expensive and noisy. They are just another thing sticking out of the deck, increasing windage, vulnerable to breaking seas and very high winds. I don’t like the way they look either. A sailboat deck shouldn’t look like the roof of a meteorological station.
I decided to find solar panels that could be glued on deck. They had to be walkable of course, somewhat non-skid and look decent. A seemingly good and affordable option was Renogy panels, but I did not want a connection box or anything else that wouldn’t be flush on deck. Renogy gets decent ratings, but not always when it comes to quality control. On the other side of the spectrum are brands like Solbian, but at a price I could not afford. I could not allocate more than about a thousand dollars for the whole installation. Unsure of my power requirements, I just needed to balance quality and capacity at the best possible price.
After some research on the Internet I found Aurinco, a small company in Anacortes Washington. Their flexible panels were just what I was looking for, though a bit expensive, at $322 for a 25W panel. I bought two Compact-25 panels and two Bluewater-18 models. They total 88W (C25 is 26W). The panels arrived very well packed and seem very well built. I’d suggest anyone contemplating ordering from them to check availability, as they do not always have all models available. I believe only a handful of people actually work there. Patrik Swanljung the owner answered my questions personally and quickly via email. I have a good feeling about the company and their products.
A charge controller is needed between the solar panels and the battery. They come in two flavors, MPPT and PWM. MPPT is more efficient, and considering the small price difference, I didn’t even look at PWM controllers. Instead of buying one controller for my four panels, I bought two 4A units ($65ea.) for redundancy. I settled on Genasun, another American company. I mounted the two 25W panels in parallel, one on each side of the deck, feeding one controller, and did the same for the 18W panels. They will never produce 88W together, but connecting them in parallel ensures that at least one of two panels can produce electricity while the other one is shaded. I haven’t checked yet, but I expect around 40W on a sunny day.
To glue the panels I used Dow Corning 795 Silicone Building Sealant, which allows for some movement due to temperature changes. It probably would be a bit easier to remove the panels than if I had used epoxy.
I sleep much better now knowing that my automatic bilge pump won’t run out of power. Hopefully the amount generated will be enough to power my VHF (560mAh) 24/7 and LED naviations lights at night. Anything else, I can do without on passages. If it isn’t sufficient, I will just have to buy one or two more panels. I could see a 25W panel on the forward hatch cover… I will buy a spare Genasun controller as soon as I can.
My other power requirements are very meager. I have only one cabin light. I plan on adding an inverter and a 12V/USB charging combo plug to run small electronic devices and occasionally charging my laptop. The big power draw would come from the Icom IC-M700 SSB radio, especially when transmitting, but I don’t plan on doing that too often. I would also rather use a small short-wave receiver with SSB, than switching on the big Icom. I will however want to have my Elecraft K1 Ham radio on most of the time, but it only draws 60mAh on receive! Another option is to add a small MFJ-9420X radio to listen and transmit on 14300kHz. I will talk more about radio in other posts… In any case, I will also need a bigger battery than the standard car battery model now installed.