Cheap vs Expensive solar panels

[Tim Good]

Q: Can anyone recommended any specific seller for low cost panels which are reaonable in quality, like the ones I got from ebay 4 years ago? See below.

Long story: Around 10 years ago I installed a branded and expensive German solar panel. Then around 4 years ago I installed 2 more cheapo solar panels along side the expensive one in series. They were all rated the same. 4 years on they're all going fine and the cheap ones are performing equally as well.

I'm now wanting to add more! But it might mean me selling 2 and buying three more due to size constraints.

 

[LONG_KEELER]

I don't know much about solar panels.

But one I installed last year has started to delaminate it's coating.

Pricewise , it was middle to low cost. I don't think it has stopped working though.

 

[JumbleDuck]

Q: Can anyone recommended any specific seller for low cost panels which are reaonable in quality, like the ones I got from ebay 4 years ago? See below.

Are you after rigid or semi-flexible?

I have a Photonics Universe semi-flexible 50W panel which is still performing OK after six years but which is very misted over. Next to it I have had two eBay cheapies. The first, from Renytek, seemed quite good but died in its second season after a young fiend of my crew stepped on it ... these cheap units are NOT load bearing! Its replacement, a Sunpower, only cost fifty quid and worked very nicely at first, but died spontaneously in its second season. I only got round to removing it this year, and examination showed that water had penetrated the connection box and one connection had completely corroded away.

I have decided to go up-market, and have a pair of Sunbeam Systems 50W "Tough" panels ready to fit. They were much more expensive - around €450 the pair - but look good. Obviously I have no idea how they will perform and last.

 

[geem]

I have had lots more success with cheap framed panels than cheap flexible panels. It seems to me that just about any framed panel seems to last well on a boat

 

[Kelpie]

I have had lots more success with cheap framed panels than cheap flexible panels. It seems to me that just about any framed panel seems to last well on a boat

Same. Go cheap, go rigid.

 

[CAPTAIN FANTASTIC]

The semi or flexible panels don't last as long as the rigid type. My semi flexible panel was OK for the first two years and then the output dropped. My two rigid panel which are over 4 years old, are performing very well

 

[Tim Good]

I have had lots more success with cheap framed panels than cheap flexible panels. It seems to me that just about any framed panel seems to last well on a boat

Yeah I should have said. My current ones are frames monocrystaline. I’d never bother with the semi flexible ones... all I hear is bad feedback.

 

[cherod]

Same. Go cheap, go rigid.

What about mounting a flexi on a solid base , does that help ?

 

[Graham376]

What about mounting a flexi on a solid base , does that help ?

Not sure that would work long term. Ideally, the panel needs an air gap for cooling and if it has a different thermal expansion and contraction rate to the base, then may well fail.

 

[BabaYaga]

On my hatch garage sits a 32W rigid, alu framed solar panel which I bought in 1996.
The brand/manufacturer was Solarex, type poly cristalline, came with a 10 year warranty. Quite expensive, as they were in those days (≈ 300€).
Still works perfectly.
My conclusion is that by the time that you can evaluate the quality of a solar panel, the model and, most likely also the manufacturer, will be long time gone.

 

[JumbleDuck]

My conclusion is that by the time that you can evaluate the quality of a solar panel, the model and, most likely also the manufacturer, will be long time gone.

With a few exceptions, that's particularly true of the eBay cheapies.

 

[LadyInBed]

I bought my two 80w semi's from TITAN ENERGY,UK SOLAR PANEL SUPPLIERS,SELLING 150W,120W,100W,80W,60W FLEXIBLE,STANDARD ALUMINIUM FRAMED AND FOLDING PORTABLE SOLAR PANELS AND SOLAR PANEL KITS FOR YACHTS, CARAVANS, MOTORHOMES,RV,CAMPERS, SHEDS, STABLES... over ten years ago.
They (and the panels) are still going and accessible - I visited them.

 

[Stemar]

I've seen a lot more dead flexible and semi-flexible panels than rigid ones. They say you can walk on a semi-flexible ones, but I'm unconvinced that it's a good idea. My rigid panels are seven years old cheap and cheerfuls, and still working as well as ever, as far as I can tell, mounted on a frame above the hatch garage. If I had to replace them now, I'd fit the same again, but I'd sooner wait a few years because I understand there are much more efficient ones coming on to the market, and it'll be a while before they trickle down to my price point.

 

[coopec]

Well that's it: cheap rigid panels!

What wattage would be realistic for each panel to mount on a 43ft ketch over the transom ?

 

[Norman_E]

I bought my two 80w semi's from TITAN ENERGY,UK SOLAR PANEL SUPPLIERS,SELLING 150W,120W,100W,80W,60W FLEXIBLE,STANDARD ALUMINIUM FRAMED AND FOLDING PORTABLE SOLAR PANELS AND SOLAR PANEL KITS FOR YACHTS, CARAVANS, MOTORHOMES,RV,CAMPERS, SHEDS, STABLES... over ten years ago.
They (and the panels) are still going and accessible - I visited them.

I see that they sell the ETFE 50 watt panels with Sunpower cells. flexible solar panel 50W They look identical even down to the label on the back and the length of the cables to the ones I bought from an ebay seller about a 18 months ago. I cannot tell how well they will last because I have not been to the boat this year but they do look to be well made panels.

 

[Tim Good]

Well that's it: cheap rigid panels!

What wattage would be realistic for each panel to mount on a 43ft ketch over the transom ?

View attachment 101252

For a ketch then people tend to have fold out ones on the guard rails or pushpit. I think you could get perhaps 150-250w on each side. They're need to be wired independently to avoid shading on one side and not the other. Mine are mountain high above the transom on an arch so get roughly the same exposure and so i wired them in series to the same controller.
But you also have the added advantage of a wind turbine on the mizzen!

 

[coopec]

For a ketch then people tend to have fold out ones on the guard rails or pushpit. I think you could get perhaps 150-250w on each side. They're need to be wired independently to avoid shading on one side and not the other. Mine are mountain high above the transom on an arch so get roughly the same exposure and so i wired them in series to the same controller.
But you also have the added advantage of a wind turbine on the mizzen!

Thanks for that: the wattage is far higher than I thought (they would be on the pushpit)

Every photo I see of a serious cruising yacht indicates they use wind turbines but no one talks about them in these forums. (Maybe I'm not looking at the right forum?)_

 

[johnalison]

My 36w semi-flexible panel was expensive when I fitted it over ten years ago. It sits in front of the garage and I take care not to step on it. A friend fitted an identical one a year earlier but his delaminated after a few years. I assumed that he was less careful.

 

[Tim Good]

Thanks for that: the wattage is far higher than I thought (they would be on the pushpit)

Every photo I see of a serious cruising yacht indicates they use wind turbines but no one talks about them in these forums. (Maybe I'm not looking at the right forum?)_

Probably because they’re horrible haha! In a marina or tight anchorage they’re dam inconsiderate. Also I see so many people mounting wind turbines next to their solar panels which is pointless. The loss in solar performancewouldn’t even be made up by the added power from the turbine. Anyone with the ability to monitor the output of the panels and seeing how much they drop just with partial shading with testify to that.

If you can get the quietest one on the market and put it up the mizzen mast then is just about justify it.

I’ve also heard the added subconscious anxiety they add to skipper and crew due to the noise. At anchor when you want to rest there’s a constant whirring which can keep you on edge.

additionally they’re mostly useful on a passage to power an electric auto pilot so for coastal cruising power is less of a problem given many people recharge on shore power and for off shore then I personally prefer my windvane steering.

I’d be going hydro power before I had to consider wind.

 

[Norman_E]

Thanks for that: the wattage is far higher than I thought (they would be on the pushpit)

Every photo I see of a serious cruising yacht indicates they use wind turbines but no one talks about them in these forums. (Maybe I'm not looking at the right forum?)_

Wind turbines used to be the best choice before solar panels became affordable, but they have disadvantages, particularly noise and the need to mount them high up to avoid contact with the whirling blades. They are now very much more expensive per Kwh of output than solar panels that except for sailors going to high latitudes they are not really cost effective. A few years ago they were cost effective because solar panels were dearer. Lots of people fitted them, and once fitted they can last a long time, which is why you still see them.