Solar panels which ones?

[Kyhendrix]

Can someone help me with which panels are best for sail boat ? Where do you all mount them at or which is best location?
Thanks
cap'n B

[atavist]

IMHO no other company can touch Kyocera for durability. I had 2 125w panels on my davits on my last boat and they got banged on docks and pilings on occasion with no damage...
Also, As far as I know, Kyocera is the only company that warrants their panels in a marine environment.

As to the question of where... That all depends on your boat and panel size... davits are a good out of the way place for them (worked well on my last boat) and on top of a hard dodger is a great place (where we are putting them on our current boat) but it all depends on how your boat is set up.

[haiqu]

It's all about size and weight vs cost. The latest semi-flexible panels have least windage and weight but are 3X the price of generic framed panels for the same output. In Australia a generic 80W framed panel can be had for $79 and that's what I'd be buying. I haven't seen anyone emphasizing brand names in advertising.

Where you mount them is dependent on sail shadows, usually on a frame attached to the transom is best. If it's only used to keep the battery topped up while not in use you could get away with a single panel on the cabin top.

[delatbabel]

Panels are getting cheaper by the day. Many small ones are better than fewer large ones, but apart from the Kyocera warranty there isn't a lot of information saying which brand is better than which other brand. I recently bought 2 x 80W Chinese made sem-flexible flat panels and stuck them on the doghouse roof, they are great because I can walk on them there and they push out up to 9A peak, although I usually get more like 6A with a bit of shadow.

Buy lots of them and mount them everywhere.

[atavist]

Originally Posted by delatbabel

Panels are getting cheaper by the day. Many small ones are better than fewer large ones, but apart from the Kyocera warranty there isn't a lot of information saying which brand is better than which other brand. I recently bought 2 x 80W Chinese made sem-flexible flat panels and stuck them on the doghouse roof, they are great because I can walk on them there and they push out up to 9A peak, although I usually get more like 6A with a bit of shadow.

Buy lots of them and mount them everywhere.

What brand are the chinese panels you bought? Pretty good price... while I like kyocera there are definite advantages to semi flexible/low profile.

[delatbabel]

Originally Posted by atavist

what brand are the chinese panels you bought?

lensun

[atavist]

Got two 100w lensun semi-flexible panels yesterday... they look pretty good though I'm not a big fan what appears to basically be seran wrap covering the PV cells... not sure I'd want to walk on them... I would worry the pressure point from a heel coming down (even just in deck boots) might break a PV cell....

that being said it's not really a concern with us as they will be mounted on our hard dodger... I just wanted the semi-flexible so that they will conform to the camber of the dodger top and be lower profile so that the bunt of the main or a line can't snag on a hard case edge...

out of curiosity, did you glue or screw yours down? I was thinking about just gluing them down with silicone then of course edging them with it as well to keep grit and grime from building up underneath.

[delatbabel]

I got rid of the plastic wrap over the top, it peels off fairly easily.

I fixed mine to the roof of the coachhouse by bolting through the roof. Spring washer on either side and epoxy sealant around the washer both under and over the panel. Going around the edges with silicone did occur to me but I haven't done that yet.

[delatbabel]

I'd be interested to hear what the peak output from your 100w panels is. With 2 x 80w panels I get a peak of about 9.3A from the 15A MPPT controller going into 12V (actually I'm guessing that's going out at around 14.4V). The controller generates a bit of heat and I'm wondering whether a 25A controller might have been a better investment.

[atavist]

I'll let you know when i get mine hooked up. i went with a 30A mppt controller.

[atavist]

Just reporting in on my lensun panels... Had them on for a couple weeks now and the best I've seen is right around 12amps... Not great but we are in Rhode Island at the moment so not the best declination for our flat mounted panels. Hopefully they will do a little better when we get further south... He longer days will help too... Right now they are just barely keeping up with our fridge...

[delatbabel]

I'm about to mount an additional 200W panel out the back along with an additional 30A MPPT controller, all of which came from eBay. I'm having a local boat yard build the frame to hold the panel. Once it's connected up I'll let you all know about what sort of output I'm getting from it.

The idea will be to have no reliance on the engine or any form of genset to charge the batteries. I have a fridge (eutectic), freezer, and autopilot (although I use the windvane whenever possible) as my main power sinks, although I also have a 1500W inverter hooked up to run a few of the AC things on board (laptop and monitor for when I'm working mostly), although that gets shut down on passage or when I'm not working. The sources are the 2x80W Lensun panels, 1 x 80W Kyocera panel, the new 200W panel, a 100W ampair wind generator, and when on passage there is a 100W aquair towed generator.

[Auzzee]

Del, I am thinking of boosting my generating power also. I have 2 x 75 watt panels. Is there any sort of balance offset charging problem with adding a panel (1 x 150w) of a different output potential?
Cheers
Dave.

[delatbabel]

Originally Posted by Auzzee

Del, I am thinking of boosting my generating power also. I have 2 x 75 watt panels. Is there any sort of balance offset charging problem with adding a panel (1 x 150w) of a different output potential?
Cheers
Dave.

The general rule is that if you have panels of a different wattage then they are also of a different voltage at normal operating power levels. The main thing to do is to run them each into separate MPPT controllers -- don't parallel 2 panels into the same controller if they aren't the same output potential.

It seems to be the done thing these days to run multiple panels in series into the same MPPT controller. The way that MPPT works, by letting the panels run at their own voltage rather than pulling the panel voltage down to the battery charge voltage, it's theoretically possible to do this even with multiple panels of different wattages and voltages. In fact you could even run 2 solar panels, a wind generator and a towed generator into the same MPPT controller that way. The main caveat is that you're asking much more of your controller's voltage conversion circuitry, and the cheaper MPPT controllers don't have much in the way of capacity there, so you're up for a larger and better quality and much higher cost controller. To my way of thinking, the way we do things on boats is to have lots of little points of failure where if one blows up it's not a major task, whereas if you have one big point of failure and it blows then your entire charging circuit is down the toilet. That to me is a compelling argument in favour of many cheaper controllers (and a couple of spares) rather than one big expensive one.

[delatbabel]

If the question you're asking is: Is there any problem with running multiple MPPT controllers in parallel, charging the same battery bank?

The answer is: No there is no problem. MPPT controllers are designed to work that way.

[ParkerMarrs]

Originally Posted by Kyhendrix

Can someone help me with which panels are best for sail boat ? Where do you all mount them at or which is best location?
Thanks
cap'n B

Hello friend bit old thread but have you got the panels for your sail boat? Even I want to install them so can you help me out..

[ParkerMarrs]

Originally Posted by ParkerMarrs

Hello friend bit old thread but have you got the solar panel for your sail boat? Even I want to install them so can you help me out..

Still waiting for reply..

[delatbabel]

Sounds like we need a new wiki page about power generation in general and solar panels in particular. I have created one here:

Power Generation - a Cruising Guide on the World Cruising and Sailing Wiki

I have 4 solar panels aboard my boat:
* 2 x flat 80W panels, "Lensun" brand, on top of the doghouse roof. I purchased these via eBay.
* 1 x monocrystalline panel, 75W Kyocera.
* 1 x polycrystalline panel, 200W Solraiser.

The panels generally give pretty good output. I'm impressed by the Lensun panels, I walk on these a lot because I need to get up on the doghouse roof to set and unset the main sail, and they still produce quite a lot of power. I'm less happy with the Solraiser panel, the peak output from it appears to be about 4A and it is a lower voltage panel (peak output at 12V compared to say 15V for some other panels) meaning that it's less easy to run its full output via an MPPT controller into a 12V system. 2 of these in series might have been a better option.

[BJSmith]

I have 2 @ 80 watt Kyocera panels for last 8 years of cruising. No problems so far. I use separate 8 amp regulators on each panel. I switched all lighting to LED lights and man what a difference. The new tricolor pulls .14 amp. vs 2.4 amp on the old Aqua Signal masthead tricolor.