Bifacial solar panels

genehelfman

Member
Joined
Nov 16, 2024
Messages
5
Fluid Motion Model
R-27 (Outboard)
I'd like to install bifacial panels on a 2023 R27, replacing the factory installed panels. Anyone have relevant experience or recommendations? Thanks.
 
I installed a 300W bifacial panel from BougeRV in place of the stock panel. It was almost plug and play on my 2024 R25 LE. I selected the panel because its max open circuit voltage was within the limitations of the factory Kisae DMT1250 Abso 50 Amp DC/DC charger. I did not want to install a Victron MPPT 100A charger. Maybe I will someday if I add even more solar. I used the mounts from the old panel. I think they are Seadog.

The panel has been great. I leave house power on at all times and never need to turn on the battery charger unless we have a long stretch of cloudy weather (uncommon in Southern California). The panel keeps up with the fridge and all 24/7 house loads. I leave the Garmin and associated electronics "sleeping" so they draw minimal power.

Even with relatively smart battery chargers I question whether it is a good idea to keep the shore charger on with lithium batteries 100% of the time. My unproven theory is that relying on the solar panel 99% of the time will add longevity to the house batteries.

Panel.png
 
Solar sizing starts with knowing what you actually consume.

I built a spreadsheet for this exact question — covers the R27, R29, and R31 with real Pacific Northwest solar production data by season. January fog through summer peak. It'll tell you exactly what you need based on your actual usage patterns.

I have 420 watts of solar on Channel Surfing. Last season, I unplugged from shore power on May 20 and didn't plug in again until Sept 1. Whether we were on the boat or not, we ran off solar. I have several tabs in this calculator that show what output one can expect with different solar configurations. Let me know if you have any questions.

Free download here: https://csurf.co/power
 
Another recommendation, no matter what panel(s) you go with, make sure they're waterproof in case you go full-submarine.
I have a pair of Custom Marine Products 210 watt panels, wired in series. They're waterproof, Johnstone Strait approved.

Here's one of my favorite solar panel photos of my boat. 😀

But did we sink 2FX.jpg
 
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I installed a 300W bifacial panel from BougeRV in place of the stock panel. It was almost plug and play on my 2024 R25 LE. I selected the panel because its max open circuit voltage was within the limitations of the factory Kisae DMT1250 Abso 50 Amp DC/DC charger. I did not want to install a Victron MPPT 100A charger. Maybe I will someday if I add even more solar. I used the mounts from the old panel. I think they are Seadog.

The panel has been great. I leave house power on at all times and never need to turn on the battery charger unless we have a long stretch of cloudy weather (uncommon in Southern California). The panel keeps up with the fridge and all 24/7 house loads. I leave the Garmin and associated electronics "sleeping" so they draw minimal power.

Even with relatively smart battery chargers I question whether it is a good idea to keep the shore charger on with lithium batteries 100% of the time. My unproven theory is that relying on the solar panel 99% of the time will add longevity to the house batteries.

View attachment 27046
Thanks! I'm pretty sure we have the Victron MPPT but have to check its amperage rating (weather a little challenging at the moment). Then I can go to BougeRV to see which unit is compatible. I like the "almost plug and play" nature, but almost often carries a wide range of possibilities.
 
Solar sizing starts with knowing what you actually consume.

I built a spreadsheet for this exact question — covers the R27, R29, and R31 with real Pacific Northwest solar production data by season. January fog through summer peak. It'll tell you exactly what you need based on your actual usage patterns.

I have 420 watts of solar on Channel Surfing. Last season, I unplugged from shore power on May 20 and didn't plug in again until Sept 1. Whether we were on the boat or not, we ran off solar. I have several tabs in this calculator that show what output one can expect with different solar configurations. Let me know if you have any questions.

Free download here: https://csurf.co/power
ChannelSurfing comes through again! It's obviously time for me to get educated. Thanks!!!
 
Thanks! I'm pretty sure we have the Victron MPPT but have to check its amperage rating (weather a little challenging at the moment). Then I can go to BougeRV to see which unit is compatible. I like the "almost plug and play" nature, but almost often carries a wide range of possibilities.
Ha! The “almost” was that the factory panel is hardwired, so I had to cut that and add MC4 connectors to plug in the new panel. A bonus is now it is literally plug and play if I want to swap this panel or add more.
 
Ha! The “almost” was that the factory panel is hardwired, so I had to cut that and add MC4 connectors to plug in the new panel. A bonus is now it is literally plug and play if I want to swap this panel or add more.
That was definitely worth knowing. Thanks! I'm headed to the boat as soon as the weather lifts to check controller specs and existing panel size.
 
That was definitely worth knowing. Thanks! I'm headed to the boat as soon as the weather lifts to check controller specs and existing panel size.

The easiest way I've found to get MC4 connectors on the boat is to buy a 3' MC4 extension off Amazon. Cut them in half. Then use 10awg butt connectors and 3:1 heat shrink to splice them on. I show this in the very beginning of this video.

 
I just replaced the factory 90W panel, two battery controller and remote display with a 400W BougeRV bifacial panel and Victron 100/50 smart controller. It was pretty easy and works perfectly for me. I had to remove the extra (+) and (-) 10GA wires going to the starter battery since the Victron only has connections for one (house) battery. The ACR will spill any extra needed voltage to the starter battery. Accessing and removing the old controller wasn't easy as I had to remove the teak bulhead in the cave. I had to cut and reconnect the wires going to the lamp behind the bulkhead in the cave as they were short. I installed the new controller where the old remote display was on the bulkhead and ran the wires thru the small hole that was behind it. I also had to install two MC4 connectors on my old panel wires that come out near the base of the mast atop the cabin. I used the mounting hardware from the old panel but had to drill new holes in the frame being careful not to damage the panel. Also had to loosen the small allen set-screws on the SS rack hardware and slide it where I needed it as necessary.
 
I just replaced the factory 90W panel, two battery controller and remote display with a 400W BougeRV bifacial panel and Victron 100/50 smart controller. It was pretty easy and works perfectly for me. I had to remove the extra (+) and (-) 10GA wires going to the starter battery since the Victron only has connections for one (house) battery. The ACR will spill any extra needed voltage to the starter battery. Accessing and removing the old controller wasn't easy as I had to remove the teak bulhead in the cave. I had to cut and reconnect the wires going to the lamp behind the bulkhead in the cave as they were short. I installed the new controller where the old remote display was on the bulkhead and ran the wires thru the small hole that was behind it. I also had to install two MC4 connectors on my old panel wires that come out near the base of the mast atop the cabin. I used the mounting hardware from the old panel but had to drill new holes in the frame being careful not to damage the panel. Also had to loosen the small allen set-screws on the SS rack hardware and slide it where I needed it as necessary.
Thanks! We already have the Victron but I'm not sure which model (weather is keeping me from playing on the boat). The Bouge 400W seems to be the panel of choice, and the MC4 connectors seem to be what everyone has to install, so thanks for telling me what to expect replacing those. I've fought with those allen screws before when repositioning the existing panels; I recall it being awkward. Much appreciated.
 
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