Remove flybridge, add solar

[rgano]

I was living aboard Calypso, my GB42 in San Diego at the Navy marina when I retired in 1989. The JTR had just been challenged and found wanting by the guy who wanted to have his trailer moved, and I lucked out in getting them to move my boat. As you state, it was either my household goods which we had had stored several years earlier when he moved from a Coronado rental house onto the boat or the boat, not both. I was given the $9,800 the Navy would pay for my HHG weight allowance to be moved to my stated destination of Jacksonville, FL and told to do with it as I pleased. I was not about to temporarily remove the flying bridge of that wooden hulled boat for the trip and found that for $9,800 I could get it the Galveston which was fine because the ICW allowed for an easy 560-mile run to my real destination of Panama City. Hauling costs would double east of the Mississippi River. I paid $4,100 to have my HHG shipped to PC, and all was well. It took ten days of daylight-only running and NO interstate travel due to height to get to Galveston, and I slept on the boat nightly.

 

[OldDan1943]

Now, all you need is a mast for your RADAR

 

[Dashash]

Roof project mostly completed. Need to install the four panels. Attached a bunch of pictures showing varying states of project completion. I'm on deployment still so the bulk of the work has been completed by a yard in Ventura while I have been at sea. Excited to return soon and finish the solar install, install the radar mast, radar, weather station, antennas, etc., and hoping check out the channel islands during the long fourth of July weekend.

 

[Dashash]

Some additional pictures.

Gen will be removed and sold when I return. Total solar array is 1800W (4x450W). Will be wired in series so electrically one panel at about 180V in full sunlight. Ultimately will charge a battery bank of about 10kWh or so. Stove will be electric so no more propane onboard. I'm looking forward to being able to anchor out without having to worry about load managing. I used to be very conscientious about having too many lights on in the evening, for instance. We'll see how it all works out. The neat part of the setup is that it should be able to power a gyro or at-rest stabilization fins (in a future install) on battery/solar alone indefinitely.

 

[slowgoesit]

Looks great! One question: Are you planning on elevating the solar cells above the fiberglass for cooling?

 

[Hyperion]

Looks great! One question: Are you planning on elevating the solar cells above the fiberglass for cooling?

Good Point. It should increase efficiency a bit.

 

[twistedtree]

What are you thinking of using for a charge controller? Sorry if it’s already been covered.

 

[Dashash]

I'll be using a single Victron 250V/100A MPPT controller for the whole array. I thought about wiring each panel separately on their own smaller controller, but ended up going with a single controller given the minimal, if any, shading I expect on the array. From my research, panels in series and at higher voltage will provide optimum efficiency and power out. We'll see.

The raised fiberglass lip around the panels is 2.5" high and the panels are 1.75" tall. That leaves 3/4" for mounting. I had the yard glass in rectangular G10 blocks for the panels to mount to so that I don't create any holes in the roof. They are a little under 1/2" tall. With the panel mounting brackets as well, the top of the panels should, in theory, be flush with the top of the raised part of the roof. Lots of words to say that, yes, there will be about a 3/4" air gab below the bottom frame of the panels.

 

[Dashash]

Some more pictures that show the mounting blocks.

 

[Hyperion]

how about airflow?

 

[Dashash]

Not sure what you're asking. What about air flow?

 

[twistedtree]

And 24V battery system, I presume?

 

[ofer]

what kind of generator will you be selling?

 

[mvweebles]

Not sure what you're asking. What about air flow?

My understanding is panel efficiency reduces as they hear up so there's a benefit to airflow beneath them. I have no idea whether the efficiency loss is small or large. Frankly, I really like your setup with engineered space for panels and wouldn't be surprised if something similar becomes more common on new designs to come.

Thanks

Peter

 

[heysteve]

Nice work! I just removed my bimini and installed three 545w panels. Wow, what a difference it made as my batteries are now fully charged by 11 AM!

If I may suggest a few things...

Consider using regular solar panel mounting rails to hold the panels. The stuff is relatively cheap and well designed. Here is one example but you can probably just use whatever your local solar store recommends. You could run two rails athwartship under each set of panels and have a system that is makes actual panel installation a breeze.

Also consider wiring the panels in two strings so you have some redundancy. The stuff is pretty reliable now days but if you're getting rid of your generator then you might what some resiliency.

You're getting into some serious charging power so make sure the controller is sized for such large panels. In my case, Victron did not make a single controller large enough for running the panels in series so I wound up running each panel to its own 100/50 controller. It added some cost and installation complexity but is very robust and maximized power output.

 

[slowgoesit]

I second Steve's comment above regarding redundancy. If it were me, I'd use two MPPT controllers, each running two of the panels. Of course, I went kind of overboard on our boat with individual controllers of each of our 8, 360 watt panels. Don't forget to put CB's on each side of the controllers as well!

One additional comment, now that the horse is out of the stable, have you purchased your panels? With that lip around the edge of the PH roof, you're now kind of locked in on the max size panel you can use. Plus, down the road, if you have to replace panels, sourcing the same size panels may be problematic . . .

Overall, it looks great, and kudo's for feeling comfortable with stepping out of the box!

 

[Dashash]

I have been looking at pros and cons of all of the voltages. 12, 24, and 48. But still researching on how the everything would piece together. Some of my big draws like engine starters and the winch are 12V DC. The simplest option would be to stay with 12V. But I like the idea of a 24V house bank to minimize wiring gauge and support the future installation of waveless electronic stabilizer fins which are 24V. We'll see.

I like the idea of two MPPT controllers. I may go that route.

Yes, I already bought the panels! And of course I did realize that I would be limited in the future to a very specific panel size to fit the enclosed space, however, it is for that very reason that the panels I chose are residential standard sized 450W panels. So I'm not terribly worried about finding replacement panels that are sized the same, or at least close enough, in the future. But great point.

 

[Dashash]

Nice work! I just removed my bimini and installed three 545w panels. Wow, what a difference it made as my batteries are now fully charged by 11 AM!

If I may suggest a few things...

Consider using regular solar panel mounting rails to hold the panels. The stuff is relatively cheap and well designed. Here is one example but you can probably just use whatever your local solar store recommends. You could run two rails athwartship under each set of panels and have a system that is makes actual panel installation a breeze.

Also consider wiring the panels in two strings so you have some redundancy. The stuff is pretty reliable now days but if you're getting rid of your generator then you might what some resiliency.

You're getting into some serious charging power so make sure the controller is sized for such large panels. In my case, Victron did not make a single controller large enough for running the panels in series so I wound up running each panel to its own 100/50 controller. It added some cost and installation complexity but is very robust and maximized power output.

Thanks for the comments. Interesting idea about the mounting rails!

 

[Dashash]

I second Steve's comment above regarding redundancy. If it were me, I'd use two MPPT controllers, each running two of the panels. Of course, I went kind of overboard on our boat with individual controllers of each of our 8, 360 watt panels. Don't forget to put CB's on each side of the controllers as well!

One additional comment, now that the horse is out of the stable, have you purchased your panels? With that lip around the edge of the PH roof, you're now kind of locked in on the max size panel you can use. Plus, down the road, if you have to replace panels, sourcing the same size panels may be problematic . . .

Overall, it looks great, and kudo's for feeling comfortable with stepping out of the box!

Do you have a picture of your solar array? That's a ton of solar. Do you also have a generator?

 

[Dashash]

My understanding is panel efficiency reduces as they hear up so there's a benefit to airflow beneath them. I have no idea whether the efficiency loss is small or large. Frankly, I really like your setup with engineered space for panels and wouldn't be surprised if something similar becomes more common on new designs to come.

Thanks

Peter

Makes sense. I'll have to rely on the movement of air on top of the panels and convection. I think it will be fine.

 

[Jeff F]

Nicely done. Boat looks great as a hardtop IMO.

 

[Hyperion]

Airflow below the panel would help greatly in lowering the temperature of the panel thereby increasing efficiency and longevity.

The perfect video to understand what I mean. This guy knows solar exceptionaly well and explains the effects clearly:

 

[CaptTom]

Interesting video, thanks!


Toying with the idea of building a "solar Bimini," good air flow under the panels is one of the challenges.

 

[Hyperion]

Interesting video, thanks!


Toying with the idea of building a "solar Bimini," good air flow under the panels is one of the challenges.

That is what I'm doing. I will try to dig up the source that said it was not as critical with the flexible ones over canvas.

 

[Hyperion]

On the 12 vs 24 volt front one thing to consider is how much of your draw is 110 and how much is 12. In my case, since I have a 110 Fridge, freezer, chest freezer, ice maker, 24v makes more sense to me as there is a softer jump from 24 up to 110. The conversion is more efficient. I will then have a stepdown transformer for the 12v systems. I am also doing for the reason you mentioned, wire size.

 

[C lectric]

***** I will then have a stepdown transformer for the 12v systems. *******
I hope you mean to feed 24V DC to an inverter to create the 120VAC.
A transformer though will not work to reduce the 120VAC down to 12VDC.

You will need another means of getting back to 12V.DC

 

[Dashash]

what kind of generator will you be selling?

It's an older model Onan 8kW MDKD I believe. Only 2500 hours or so.

 

[mvweebles]

Airflow below the panel would help greatly in lowering the temperature of the panel thereby increasing efficiency and longevity.

The perfect video to understand what I mean. This guy knows solar exceptionaly well and explains the effects clearly:

Quite the propeller head video - liberal use od YouTubes 10-second fast forward double-tap feature. Shows approximately 15% efficiency loss due to heat gain.

Thanks

Peter

 

[twistedtree]

I have been looking at pros and cons of all of the voltages. 12, 24, and 48. But still researching on how the everything would piece together. Some of my big draws like engine starters and the winch are 12V DC. The simplest option would be to stay with 12V. But I like the idea of a 24V house bank to minimize wiring gauge and support the future installation of waveless electronic stabilizer fins which are 24V. We'll see.

I like the idea of two MPPT controllers. I may go that route.

Yes, I already bought the panels! And of course I did realize that I would be limited in the future to a very specific panel size to fit the enclosed space, however, it is for that very reason that the panels I chose are residential standard sized 450W panels. So I'm not terribly worried about finding replacement panels that are sized the same, or at least close enough, in the future. But great point.

OK, whichever voltage you select, just be sure the controllers are sized appropriately. Figure your output current at 125% of rated solar wattage, so 1800W/12V*1.25 = 187A. That's more than the Victron you mentioned can handle. Also watch the input voltage. You should be sized for the panel open circuit voltage (Voc) times 125%. I believe NEC still requires 144% over rating. For service and maintenance I highly recommend breakers between the panels and controller, and they are hard to find in ratings above 125VDC. Voltages above that you usually need to use fuses in pull-out holders.

 

[Hyperion]

***** I will then have a stepdown transformer for the 12v systems. *******
I hope you mean to feed 24V DC to an inverter to create the 120VAC.
A transformer though will not work to reduce the 120VAC down to 12VDC.

You will need another means of getting back to 12V.DC

Nope, I meant 24v DC to 12v DC:

Something like this one

https://www.amazon.com/dp/B01BF5BQLA?tag=bravesoftwa04-20&linkCode=osi&th=1&psc=1&language=en_US

Have not drawn up the design yet.