Solar panel recommendations to buy, 350-400 watts

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slowgoesit

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Vessel Name
Muirgen
Vessel Make
50' Beebe Passagemaker
We are moving ahead on our solar upgrade, and were wondering if anyone has a PERSONAL recommendation on a source for solar panels they can recommend from RECENT experience.
I can google as well as anyone else, but a personal recommendation goes a long way!
What we are looking for:
mono crystalline

6 panels total
330 watt to 450 watts each
rigid panels
size 40" ish, to 70" ish.
Prefer bare aluminum frames

I am leaning toward using Victron MPPT controllers and MC4 connectors.
We are located in Port Orchard, WA, but we will probably order on-line.
Thanks in advance!:thumb:
 
I bought my panels from Solaris-shop.com. They don't list the exact panels I bought anymore, but they've got other suitable options. Supply is short right now, so their selection doesn't look as good as it sometimes is. When I ordered, my panels came via freight truck on a pallet. Easy enough to un-pack the pallet at home and then bring them down to the boat.

Mine are the Trina Solar TSM-410-DE15H(II) 410W panels. So far they've been great, as have the Victron MPPT controllers. I'm using the Smartsolar 100/30 with 1 controller per panel (only 2 panels on my boat right now). For wiring the panels to the controllers, I bought MC4 connectors and the kit to crimp them on and being that I only had 1 panel per controller (so only about 10 amps max on the panel side), I used some regular Ancor 12/2 duplex tinned wire.

It all went in last spring and worked beautifully all season (and is working well this season too).
 
rslifkin, thanks for the info. I am finding it difficult to find panels whose manufacturers list an IP rating for the panel itself. Several manufacturers list IP ratings (resistance to water intrusion) for the CONNECTORS, or the JUNCTION BOX, or, but not the actual panels. IP68 appears to be the typical rating for the connectors/junctions boxes, which is really good, just not sure about the panels themselves . . .
 
The panels are meant to be out in the rain and weather on a house or other installation, so other than possible salt spray (which doesn't seem to be an issue for people in practice), I don't think being installed on a boat is any worse than the environment they're designed for. Provided you don't totally submerge the panels, I don't think anything on a boat will hurt them.
 
Since you are in WA, check out Platt Electric. They carry several different brands and I bought my panels from them. An advantage of buying from a local source rather than online is that you can buy smaller quantities more readily rather than bulk lots of panels that you would use for a house, which is what many online sellers offer.
 
Since you are in WA, check out Platt Electric. They carry several different brands and I bought my panels from them. An advantage of buying from a local source rather than online is that you can buy smaller quantities more readily rather than bulk lots of panels that you would use for a house, which is what many online sellers offer.


Thanks Ken. I see a couple of panels they carry that would work!:D
 
https://www.passagemaker.com/
A good article on DIY install of solar panels. These panels are designed to excel with shadowing concerns. Not sure if you will have this issue. I'm looking at doing the same thing as you. The author did a great job listing all the parts necessary for a DIY solar project.
 
https://www.passagemaker.com/
A good article on DIY install of solar panels. These panels are designed to excel with shadowing concerns. Not sure if you will have this issue. I'm looking at doing the same thing as you. The author did a great job listing all the parts necessary for a DIY solar project.

The article didn't come through. It's a March 7th edition. Article is "The sound of Silence."
 
The Sunpower Maxeon panels are preferred in this part of the world for performance. Highest efficiency so most bang for the square foot. Good shading issue management in panel design. Not sure if you can readily source them where you are.

But you should carefully consider panel wattage size if using Victron controllers, otherwise your controller cost will easily exceed you panel cost. eg If you have a pair of 350W panels in parallel then you can use one Victron 100/50 controller. But go to larger wattage - say 400W - and you then need to go to the 150 series controllers, and will almost double your controller cost.

I run panels in parallel - 3 pairs of Maxeon 345W panels, and one pair of Trina 330W panels, and 4 x Victron 100/50 controllers. And power to burn as it were....
 
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The Sunpower Maxeon panels are preferred in this part of the world for performance. Highest efficiency so most bang for the square foot. Good shading issue management in panel design. Not sure if you can readily source them where you are.

But you should carefully consider panel wattage size if using Victron controllers, otherwise your controller cost will easily exceed you panel cost. eg If you have a pair of 350W panels in parallel then you can use one Victron 100/50 controller. But go to larger wattage - say 400W - and you then need to go to the 150 series controllers, and will almost double your controller cost.

I run panels in parallel - 3 pairs of Maxeon 345W panels, and one pair of Trina 330W panels, and 4 x Victron 100/50 controllers. And power to burn as it were....


I am looking at 6 each, 380 watt panels, with 3 x Victron 100/50 controllers. Proper circuit breaker protection, then on to the main 12v buss.
 
You might be ok, but I assume you are aware that the 100/50 controllers are rated for 700W @ 12V? I think they can auto de-rate if input wattage at any particular time exceeds the limit for any length of time, but you are going to 760W which is significantly above spec.

In practice my pairs of 345W Sunpower panels have delivered Max PV of 734W. And the Trina pair of 330W have had a Max PV of 736W. Only for short periods no doubt. No idea if the controllers have de-rated or not. But you my want to check how long you can exceed spec before the smoke gets out.
 
I assume you have exactly mapped out how you are going to place your panels. I gained nearly 25% by actually using more but smaller panels (250W) and being able to fit around roofline obstructions etc.

Cheers
 
You might be ok, but I assume you are aware that the 100/50 controllers are rated for 700W @ 12V? I think they can auto de-rate if input wattage at any particular time exceeds the limit for any length of time, but you are going to 760W which is significantly above spec....


This is an important point often missed. The Victron website has a free calculator used to determine the equipment needed based upon your intended configuration. Well worth the effort to figure out how to use it - it's a bit confusing.


One other recommendation would be to up-size your wiring from the panels to 10 ga. It's not that much bigger for fishing through tight spaces and will reward you with less voltage drop.
 
You might be ok, but I assume you are aware that the 100/50 controllers are rated for 700W @ 12V? I think they can auto de-rate if input wattage at any particular time exceeds the limit for any length of time, but you are going to 760W which is significantly above spec.

In practice my pairs of 345W Sunpower panels have delivered Max PV of 734W. And the Trina pair of 330W have had a Max PV of 736W. Only for short periods no doubt. No idea if the controllers have de-rated or not. But you my want to check how long you can exceed spec before the smoke gets out.

As long as you never get over 100V on the input (worst case being panels in full sun, no load on a cold day), you won't hurt the controller. Even hooking 1000w up to it won't hurt it, you'll just never see full output from the panels (as the controller won't output more than 50A on the battery side no matter how much input power is available).

50A controller output with 760w panels is a little more over-paneled than I'd want, as you'd be noticeably limited in the bulk charging phase if you're under optimal sun. You'd never see the full panel output, although once you're in absorption you'd get close. At 14.4 volts you'd get 720w (the 50A limit is constant regardless of battery voltage).

If looking at a pair of panels in that size range, I'd go for 2x 100/30 controllers (or a single 150/60) instead. I went for 2x 100/30 with my pair of 410w panels. The panels aren't angled identically due to deck camber where they're mounted, so separate controllers is a bit better for power output. And 2x 100/30 was about the same price as a single 150/60 anyway.
 
I added 500W of Renogy panels and MPPT controller in 2020 and they've worked great.

Not sure if they have the size you're looking for, but maybe worth a look. Two of the panels are visible in this shot on the fwd port rail.

https://www.renogy.com/
 

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I have a similar set up

it is RARE that you wil get the rated FULL output of a panel, so yes my panels are 15 % 'bigger' than the rated output, as long as they never go over the max V the Victron MPPT can handle, which is OK :)
 
Hi Slowgoesit. Check out Solarcity. https://www.solacity.com/ They are up here in the great white north (Canada) but their web site is loaded with great solar information and pricing. I have done two boats with solar. Last one as last year. You should get a good feel. If you want to call them ask for Rob Beckers the owner. He is a walking guru and could probably give you a purchase source closer to home.
Cheers
Barrie
 
Hi Slowgoesit,

I recently bought solar panels directly from Hong Kong. This is the second time I've done this, and both times it's worked out fine. Two things - first, many of the spec sheets posted by China manufacturers have errors. For example, the spec will claim 100W, but when you multiply the max current by the operating voltage, it's only 75W. Or similar. Be careful about getting the actual wattage. Second, shipping has now become very expensive (7 years ago it was a lot less) so do your homework to decide whether you'll save enough to warrant the uncertainty of dealing directly with a supplier in PROC.

I have had good service from <jet@sunsunsolar.cn> but this is not an endorsement, only a comment. I needed panels of a specific shape to fit a specific location on my trawler, and Sun Solar had the product, and their specs checked out. I have not tested the panels since they arrived and were installed. Aligning a panel in full sun at 90 degrees and measuring current and voltage is tricky.

I also bought an MPPT controller from them. I know of no China-based supplier that actually makes a 'real' MPPT unit. They claim it's MPPT but in reality they are mostly PWM (pulse width modulation) which is not the same, but cheaper to build and almost as effective. Your $$, your choice.

Rick Hudson
 
Despite the slaughter of Renogy in a recent thread, I installed 2 x 320watt panels this summer and have been satisfied. Home Depot or Amazon seem to have the best prices.
 
Despite the slaughter of Renogy in a recent thread, I installed 2 x 320watt panels this summer and have been satisfied. Home Depot or Amazon seem to have the best prices.

I'm in your camp. I have Renogy products in my RV and like them. The naysayers can....naysay.
 
Here's a reference to the article for those of us that don't have subscription to Passagemaker.

https://www.passagemaker.com/lifestyle/the-sound-of-silence-2022

Bruce



https://www.passagemaker.com/
A good article on DIY install of solar panels. These panels are designed to excel with shadowing concerns. Not sure if you will have this issue. I'm looking at doing the same thing as you. The author did a great job listing all the parts necessary for a DIY solar project.
 
Depends on what you want.
If limited space you probably need to get the most efficient and pay the price
If space is not such an issue I will always go near new and do my hit for the environment by recycling. (-;

I can still buy less than 1 year old, balance of 10 year warranty remaining 270watt solar panels made by a tier one company for around $50 each.

We have 9 for 2.5kw running through a midnite classic 150mppt.
 
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I have “solarized” two of our boats, the first was a 35’ sailboat with 2 large panels mounted on a custom-built aluminum arch on the stern, and our current boat, a 38’ trawler with a covered afterdeck. I’ve also designed several installations for friends. Here’s my 2 cents:

The MC4 connectors use very small diameter wires; you need all the copper you can get to reduce loss. If at all possible, use junction box-equipped panels instead. They are more difficult to find, but I think it’s well worth it. I ran heavy gauge cables (forgot the exact AWG, but it was at least 12 AWG) from each panel separately to a Blue Seas fuse box, and then to a single MPPT controller. There’s a breaker between the controller and the house batteries. I don’t like stringing the panels from one MC4 connector to other panels; the loss is too great. Also, you should have the capability to isolate a dead or shorted panel which you cannot do if you string the panels via the MC4 connectors with just one cable leading to the controller (or even multiple controllers for redundancy). On my sailboat, I had a drunken chowderhead in a J-24 smash two of my panels; I only needed to pull the fuses for those panels to remove them from the circuit.

Another point: I also like monocrystalline panels, but the polycrystalline panels are just a hair less efficient than the mono, but at a much lower price point. I found it wasn’t worth the extra $ at all.
 
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Size of the wiring to the MC4 connectors on a given panel is often published in the datasheet. For my big 410w house-sized panels it's listed as 12 awg (which is what I used for the rest of the run from the connectors to the MPPT controllers anyway).
 
Thanks for the tips on more places to look.
Oh, and on Renology being "trashed", I don't think it's the panels, it's Renology's lack of customer support if you DO have an issue.
 
Ordered 6 x Victron Smart Charge Controller 100/30, Cerbo GS, and Touch 50.

Six gang CB box and 6 breakers, more to use as switches to isolate each panel, than to protect the wiring.

Also ordered good quality MC4 connectors, and 500' spool of dual insulated, 10g wire. Then two more batteries, so I will end up with 4 ea, 3 battery "pods" wired in parallel to buss, then from buss to main buss in ER.

Total length of wire in a pod circuit will be about 8 feet, all wired with 4/0 anchor tinned wire.
Ordered Six Sil-360 NX panels made by Silfab Solar. Ordered from Platt Electric in Bremerton. They'll be in today. The 380's and all the other ones I was looking at were all back ordered 2 to 3 months. The Sil-360 NR panels are one of the few that state they are "Salt Mist Corrosion Certified". Junction box is IP67 rated. I was restricted in size to no more than 72" long due to the size of my Bimini. I wanted to retain a strip down the middle about 20" wide to walk in.
I'll keep this updated as the work progresses.

Next step is to install the new Bimini. Fabbed out of 3/16" 6061 aluminum, with 1/4" stringers, backer plates installed to reinforce where hanging chairs will attach. Uprights are 2 7/8" sch 80 pipe, with tabs on underside of Bimini for uprights to slide into, allowing room for adjustment as necessary. Fabbed in two halves, each 10'
long x 7' wide, bolted together in the middle, and bolted to the aft end of the aluminum pilothouse, continuing the existing crown/arch of the pilothouse for strength/water shedding. Rear of the arch will be reinforced with a "truss" on the back/top that will double as the rest for the end of the boom. Pics attached. Note the hardpoints on the top of the Bimini to support the rails to attach the solar panels. Enjoy!:dance:
 

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