Solar Panel Upgrade

[John Stone]

As part of the engine install and battery upgrade (T105s 225 AH battery bank wet cell replaced a 100 AH AGM) we are also upgrading our solar panels. I have used a single 30 watt semi flexible Gantz panel on a 10' power cord as our sole source of energy production for six years. It worked exceptionally well. The only power requirements we had were charging phones, a tablet, run a few interior LED lights when it was too hot for our kerosene lamps, and run the AIS. But with the addition of adding LED navigation lights and a Raymarine depth sounder it seemed a good time to increase the battery bank and thus keep the energy system balanced by increasing the solar panel collection capabilities as well. You can read about the decision process for the battery bank here. https://farreachvoyages.net/2021/06/04/ ... #more-2091

I would have simply added another 30 watt Gantz panel but they are no longer made. And truth be told though I like the thin semi flex panel they proved to be fragile. My first one gave up the ghost after two years. I don't know how much longer the current Gantz panel will last. So, I have been researching replacement solar panels for several years. I didn't want panels that required permanent mounting hardware like an arch. I like having the panels on flexible loose power cords that allow me to best position the panels relative to the sun. Doing so, increases the panels collection capability because I can keep them in the sun when they might otherwise be in the shade if permanently mounted in one location.

Thin flexible panels need to be mounted on a hard backer plate or over time they will crack. Plus, usually the positive and negative wires exit the panel in opposite directions making it cumbersome to use them on a loose power cord. Standard panels are heavy and not constructed to move around and be tied off to the inverted dinghy the way I prefer. Thin panels also have a very short warranty.

This past winter I discovered Zamp Obsidian Series Panels. They are not flexible. But they are 1/3 thinner than standard panels. They can be easily mounted to a backing plate which I can then drill holes into for lanyards. They are high output and have a 25 year output warranty while my Gantz was warranted for one year. The panels come with a single 10' power cord. They are are made in America.

I bought two 45 watt panels to replace the single 30 watt Gantz. They are 14"x31.5"x.67". Each will be on a separate MPPT controller and collect energy independent of the other. I will essentially triple my solar collection capability and double the battery bank.

I have not worked out all the details but I'll have it sorted out and the installation completed before my planned voyage to the West Indies in late Nov.

[fmueller]

Thanks for posting John ... I'm trying to figure if its at all possible for me to "solar up" on my small boat.

I'll be interested to see how you wire up.

Fred

[John Stone]

Sure thing Fred. I just finished installing the Obsidian 100 watt panel on our Jeep. I wired it through a Victron Bluetooth MPPT Smart Controller 75/10. It was pretty simple. So far works good. The smart controller uses an APP on your phone so it's very convenient. No other battery monitor requires.

I am not going to use the Victron controller for the boat though. I don't want a Bluetooth controller that requires me to have a working smart phone to use it. I'll stay with the Genasun 5A MPPT controller that runs through a dedicated wired Victron BVM 700 battery monitor. Dead simple. Same one I used for last five years. I have a good idea how I'll rig the panel up to an acrylic backer board. Happy to share what I come up with.

[John Stone]

Got the first solar panel assembled. Purchased a white plexiglass/acrylic panel from McMaster Carr that that is machinable without cracking. Serves as backer board. Also purchased non marking binding. Not sure how well the binding will work.

The panels need air under them to keep from over heating. So I cut a series of four inch diameter holes in the back and also installed some spacers. I drilled 1/4" holes at the corners for lanyards to secure the panel same as on my old 30 watt Gantz panel.

I also built a new fiberglass box for the hella connectors. I can run two wires down the stanchion in the saloon same as I routed the single wire before. So two 45 watt panels on flexible cables. One on each side of the boat or I can move them to the same side if that's where the sun is best. Each panel runs through its own MPPT controller so if one panel is in the shade the other is operating at max capacity.

Will have it hooked up in the next couple days. If this panel works as planned I'll assemble the other the same way.

[John Stone]

Test fired the panel today. Started right up. Start on the second panel tomorrow.

[John Stone]

Installed the solar box with the connectors and wires and bedded with butyl. Will give it a couple days to squeeze out. I previously drilled the deck, dug out the core and installed 1/2" G10 plugs I then tapped. The fasters are 10-24 machine screws.

I also assembled the second solar panel with the backer board. So it's ready to go.

Tomorrow I will install the MC4 connectors below deck and run the wire to the Gensun GV 5 MPPT controller.

I had a new zipper installed in the genoa to make it easier to zip the bonnet off and on. Hope to be able to test it out a couple times before departure.

[Jim Walsh]

Took the captive chains off the caps….at some point you’re going to be wondering where you stored those caps, at lest I would.

Test fired the panel today.

Fired is a term which I would avoid had I done the electrical work.

Nice neat job. Must be great to be prepping for a cruise to warm water. I’m jealous.

[John Stone]

Took the captive chains off the caps….at some point you’re going to be wondering where you stored those caps, at lest I would.

Nah. 99 percent of the time the panels are plugged in. If I left the chains on they would be in the way and probably get broken off. I'll keep the caps in the nav box when the panels are plugged in. Same as I did for the cap for the single panel I had before.

Test fired the panel today.

Fired is a term which I would avoid had I done the electrical work.

Weren't scared a bit. I knew it would work. Nothing to it.

Nice neat job. Must be great to be prepping for a cruise to warm water. I’m jealous.

Thanks Jim. I appreciate that. Got one small event I have to clear next Thursday. I get through that OK then we splash the boat the following Monday. If not, then probably no winter voyage this year. I'm not sweating it though. It's all going to work out in the end. If it doesn't, then it's not the end.

[John Stone]

Completed the wiring of the second panel. Connected both panels. Energized the system. Not much light. Cloudy and the sun is low late in the day. I'll know more tomorrow. But I'm checking it off the list.

[Jim Walsh]

Nice neat installation. Just wondering what size wire you used from the panels to the controllers. I’m an electrical nincompoop….but I’m safe because I recognize my shortcomings.

[John Stone]

Nice neat installation. Just wondering what size wire you used from the panels to the controllers. I’m an electrical nincompoop….but I’m safe because I recognize my shortcomings.

Ha, you're sandbagging me. I have watched you for years. You are a pro through and through.

I used 12 AWG. Couple reasons. The panels are wired parallel vice in series. So there is no combining of amperage anywhere along the path. 12 AWG matched my 3 percent calculator drop distance for panel that can only make about 3.5 amps max. Also, those deck connectors I use can only accommodate 12 AWG.

Electrical is not my comfort zone. So I have to plan it very carefully.