Solar panel - buying tips

[Storyline]

To supplement our wind generator I am thinking of buying a solar panel. Realise that there are a lot of threads on this topic but as the technology is so fast moving (& prices) I would appreciate any pointers as to which one to get.

Salient info;

Maximum power: 100w This is the maximum power that our existing controller (for the wind gen) will accept so I only need the panel and no regulator etc as apparently I can wire directly to the hrdx.
Sailing area: nw Scotland
Boat: 36' centre cockpit sloop without any gantry or easy place to mount it. (Westerly Conway)

I have read some reports that some panels will not work if shaded in part but I cannot think of anywhere to mount it where it will not have some shadow sometimes. Have been thinking that smaller panels totalling 100w might be better, then I could maybe mount them either side of the aft hatch but they would have to be able to be walked on (risk of slipping ?). I would prefer a permanent installation but might have to compromise (thinking of deck socket and wandering lead).

The panel would really only be used when we are sailing as the wind generator is more than able to keep the batteries topped up when we are not onboard (Scotland !)

Any tips and in particular brands or places to buy would be gratefully received. Although I do not want to waste money, considering the time taken to install it I am prepared to buy a good quality one.

 

[Kelpie]

I'm also shopping for solar panels just now. Annoyingly, the lowest price people on eBay refuse to deliver to the islands.
I was on the phone to one this morning 'modelwholesakeuk' who claim to deliver everything by Royal Mail or Parcelforce, yet still refused to deliver to me. These services are flat rate across the UK so it costs exactly the same to deliver to me as to anybody else. I informed them that I will be taking my business elsewhere!

(Sorry, I realise this isn't very helpful, just needed to rant about it!)

(Oh and btw 100w is pretty big for a roving solar panel, best suited to a permanent installation)

 

[Storyline]

I'm also shopping for solar panels just now. Annoyingly, the lowest price people on eBay refuse to deliver to the islands.
I was on the phone to one this morning 'modelwholesakeuk' who claim to deliver everything by Royal Mail or Parcelforce, yet still refused to deliver to me. These services are flat rate across the UK so it costs exactly the same to deliver to me as to anybody else. I informed them that I will be taking my business elsewhere!

(Sorry, I realise this isn't very helpful, just needed to rant about it!)

(Oh and btw 100w is pretty big for a roving solar panel, best suited to a permanent installation)

Not sure of your time scale but we are up at Ardfern in 3 weeks so could bring anything up if you have it delivered here.
(probably too far from Skye but the offer is there)

Edit: to pick your brains - which panels have you chosen ?

 

[vyv_cox]

Our experience of flexible panels when sailing is very poor. Our 30 watt one needed to be attached at six points but continually flapped and was generally a nuisance. Once arrived of course it needed to be moved. Conversely, we have had the same semi-flexible 38 watt panel screwed to the deck aft of the mast for almost 20 years now, it does not provide a huge current but is used throughout the winter to keep batteries up.

Although some people object to arches on aesthetic grounds there really is no substitute. Absolutely no hassle apart from cleaning them once a month or so, they provide power from dawn to dusk in the best possible location to minimise shadows.

 

[Kelpie]

I haven't made a final decision on panels yet, but will be looking for rigid monocrystalline ones. The space above the hatch garage could take a single 50-60w panel, or a pair of 20-25w panels side by side. I'm quite tempted by the latter option because, in theory, it means that at least one of the panels is unlikely to be shaded by the boom. Am I thinking correctly on this?

 

[Kelpie]

Not sure of your time scale but we are up at Ardfern in 3 weeks so could bring anything up if you have it delivered here.
(probably too far from Skye but the offer is there)

Thanks for the offer but yes it is a bit far...

 

[mackhfervand]

You can get the best manufacturers or suppliers of the products at e commerce websites. These are global market platform, providing with the comparing and selecting the best deal.

 

[Storyline]

You can get the best manufacturers or suppliers of the products at e commerce websites. These are global market platform, providing with the comparing and selecting the best deal.

Thanks - do you mean Alibaba ?

Edit: oh, and welcome to the forum

 

[Champagne Murphy]

We have a Sunware (Marlec supplied) 69w on the roof just forward of the mast. We also have a much cheaper 60w Titan just astern of the mast. On a sunny day together they provide over 4A if the demand is there. I put them through a Morningstar Sunsaver Duo regulator which lets me charge two banks either 50/50/ or 90/10.
Sunware are allegedly the best but Titan, at around 1/6 of the cost are hard to dismiss.

http://www.pennygreenfingers.net/60w80w100w-semi-flexible-solar-panels.aspx

http://www.marlec.co.uk/online-shop/

Customer service from Marlec was second to none. When I had some concerns they took the panel back and tested it FOC even though it was out of warranty-don't worry, it was just a dry electrical joint in the junction box that I fitted, nothing to do with the panel
Equally Pennygreenfingers seem to have good reviews.

They've been a revelation, quiet and productive. If only I had more deck space!

 

[Storyline]

We have a Sunware (Marlec supplied) 69w on the roof just forward of the mast. We also have a much cheaper 60w Titan just astern of the mast. On a sunny day together they provide over 4A if the demand is there. I put them through a Morningstar Sunsaver Duo regulator which lets me charge two banks either 50/50/ or 90/10.
Sunware are allegedly the best but Titan, at around 1/6 of the cost are hard to dismiss.

http://www.pennygreenfingers.net/60w80w100w-semi-flexible-solar-panels.aspx

http://www.marlec.co.uk/online-shop/

Customer service from Marlec was second to none. When I had some concerns they took the panel back and tested it FOC even though it was out of warranty-don't worry, it was just a dry electrical joint in the junction box that I fitted, nothing to do with the panel
Equally Pennygreenfingers seem to have good reviews.

They've been a revelation, quiet and productive. If only I had more deck space!

Thanks for the links - exactly the sort of first hand info I was hoping for

Maybe a revelation to you but iirc is not Pill Mill somewhere in Norfolk/Suffolk ? According to Bob Flowerdew on GQT you are lucky to be based in one the sunniest and driest parts of the UK - somewhat different to where we are on the nw coast - although Tiree which is not far away is supposed to be sunny.

Anyway, going to jump in and have a go. Thanks again.

 

[JumbleDuck]

I haven't made a final decision on panels yet, but will be looking for rigid monocrystalline ones. The space above the hatch garage could take a single 50-60w panel, or a pair of 20-25w panels side by side. I'm quite tempted by the latter option because, in theory, it means that at least one of the panels is unlikely to be shaded by the boom. Am I thinking correctly on this?

The bigger panel is almost certainly laid out as two smaller arrays of panels under one cover: that's how it is with both my 50W panels.

 

[Champagne Murphy]

Thanks for the links - exactly the sort of first hand info I was hoping for

Maybe a revelation to you but iirc is not Pill Mill somewhere in Norfolk/Suffolk ? According to Bob Flowerdew on GQT you are lucky to be based in one the sunniest and driest parts of the UK - somewhat different to where we are on the nw coast - although Tiree which is not far away is supposed to be sunny.

Anyway, going to jump in and have a go. Thanks again.

I wouldn't believe anyone from GQT at the moment! Its as wet here as anywhere but Lancashire!
Even in shade they produce quite a bit, saves running the engine and if you combine it with LED lighting it makes a huge difference.

 

[Norman_E]

I would not put in a single 100 watt panel for a number of reasons, not least its size and weight, but also the fact that a big hailstorm could wreck any panel, and its better to have a few smaller ones. I have bought but not yet installed a couple of 20 watt panels, and intend ultimately to have five of them. I bought these. http://www.ebay.co.uk/itm/251131513443?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT The same company have larger panels at less than £1 per watt. The ones I bought were over £30 each at the time, but the real advantage of the small panels for me is that I can carry two at a time out to Turkey when I go to the boat.

 

[Storyline]

The regulator i have (Rutland HDRX) accepts a max of 100w, can anyone see a problem with wiring a number of small panels in parallel to it ? Also of different makes.

 

[ghostlymoron]

Current is current regardless of where it comes from so the type or manufacturer is immaterial. I've had three semiflex type which have performed well and are easier to find a place for. I understand that the output per m2 is less than a rigid but the advantages outweigh the efficiency I think. The shading issue is exaggerated IMO.

 

[Graham_Wright]

Nobody has mentioned guard rails. At anchor, the panels could be tilted to the optimum angle. Underway, I'm not sure they would work too well. I've seen a few such fits in France.

 

[JumbleDuck]

Current is current regardless of where it comes from so the type or manufacturer is immaterial. I've had three semiflex type which have performed well and are easier to find a place for. I understand that the output per m2 is less than a rigid but the advantages outweigh the efficiency I think. The shading issue is exaggerated IMO.

I have two 50W semiflexible panels (plastic backing) and I get 4A out of them in bright sunshine, 3A in normal sunshine and 1A on overcast but bright days. I agree about the shading. I checked with the boom shadow along both panels on a sunny day last week and they were still giving 2A. It's a different matter if you physically cover them, but a shadow is actually quite well lit from scattered light and there seems to be enough there to keep the shaded cells ticking over.

 

[[3889]]

I have had three 100w flexi panels over the last couple of years from Pennygreenfingers. Output-wise they are fine and I regularly stand on them without issues, but the cable attachment is the weak point, failing if subject to very modest strain. My current panel has been drilled to accept cable ties for strain relief and I have reinforced the connector box with lashings of Sikaflex. It is secured to the foredeck with 3M dual lock and has remained in place after 6 months and 2000 miles with up to 45 knts across the deck. Dual lock allows the panel to roam in settled conditions at anchor to maximise output. The panel is very light, less than 2 kg, and very flexible.
I looked at more expensive panels but there seems to be a very big jump in price, > 300%, once sourced from outside ebay and I'm not sure that the cable connection would be significantly stronger so I have stuck with modifying the cheaper products based on past experience.