Recommendations for solar panels

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mocruising

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I have spent the last few hours looking at past threads on solar panels. Basically I know what I want a large bank of flexible solar panels to keep my batteries up while the boat is idle.(Six months of the year) Can anyone who has had good experience with flexible panels make any recommendations wrt to supppliers.
 
Can't recommend a supplier - mine are solid panels - but do bear in mind that they get dirty quite quickly - I clean mine daily to get full output. When I go back to the UK for a fortnight, soon, I shall leave the fridge running, but I wouldn't for a much longer period.
 
BP ones are good, remember to buy the regulator as well if you are leaving it for that amount of time.
 
I have a single solid 45watt panel (with regulator) that happily keeps the fridge running and the domestic bank of 3 batteries stay around the 13volt mark. Bring in the starter battery and the 2 bowthruster batteries to charge from the panel and we go down to about 12.8 volts. The panel can be walked on with no problems.

Bought from a caravan shop (Cross Country Caravans at Shillingford Bridge in Oxfordshire; ask for Chris). Can't remember the manufacturer name but they did larger rated panels than the one I bought.

Steve
www.seraph-sailing.com
 
You only need a small panel to trickle charge while the boat is idle.
To run a fridge while the boat is in commission needs 50wts or more.
I've had good experiences with Sunware panels which are designed to
be walked on in marine use. Not the cheapest though.
My understanding is flexible panels are not so powerful as rigid
but I can't remember why!
 
Re: Recommendations for Solar Panels

Could understand need if moored away from land, but if the boats parked in a med marina - are panels your best solution to whatever charge issue you've got?

1. They will get dirty and steadily decrease in efficiency over a 6 month unattended period.
2. When you get to the boat you'll probably connect to shore power on arrival - and probably have all batteries up to speed by next morning anyway.
3. Good panels are relatively expensive - and they do not last forever - and one needs to store them on the boat when not being used.

Surely it's might not be as expensive overall, and possibly better for the boat, to organise for someone to visit each 4 weeks. A hose down, clean off, and whilst on board connect it to shore power to give the batteries a quick days boost?

IMHO you'd get a lot of such days for what you might spend on solar panels - and you boat should be in better order when you arrive back.

Cheers
JOHN
 
Anchoring manners

It is nice to have solar power to run a fridge whilst at anchor. I manage on a nominal 60 watts in the Med with temperatures in the mid 30s.

If you get someone in an anchorage who runs a motor or a generator they are not welcome. It is worth keeping away from motor boats or yachts over 12 m as they tend to be the ones. [Not all if you are about to be offended.]

I had a family anchor a motor boat about 10 metres away along side and run their generator. They couldn't hear the discharge because they were about 5 metres above the water, whereas I was about a metre but they 'needed the generator to run the air con'.

Maybe I am oversensitive?
 
Re: Anchoring manners

dont flex flexable panels as they will reduce power up to none at all and youll need a "thing" to keep them fit ie all charging at the same rate no matter some are shaded----ok tonight im not fit to post nor walk to the key¨!

ridgide work best cost half and last longer! ive been sailing this year with my 18w and had light useing 25w quarts lights charged my phone and played music @5w !for 1 hour a day i will add a 40w later as my 85w is to big but rns a fridge in the med!!!!
 
Couple of general points .
The flexible ones that I have experienced and seen in the tropics don't have the build quality or waterproofing or output . And check that they produce an output when PARTIALLY in shade(which could be the shadow from a single stay ,for example).
I still have a 10 year old 18w Solarex rigid thin panel that is fine (but does not like partial shade either ).
 
Excellent point about the partial shading, especially on a sailing yacht. My two large Solara panels (rigid) were bought from Barden Batteries (who claim to be such experts) and I was assured before I bought them that NONE of the panels they sell fails to provide an output when partly-shaded. These ones don't. They are a German panel designed for the roofs of buildings, not for use on yachts or in marinas and when a shadow falls across part of the panel, the output collapses. I could have taken them back but it would all have been very difficult after installation so I live with it. It would have been nice to have known before buying them.... caveat emptor /forums/images/graemlins/mad.gif
 
No problem you need a small cheap "thing" which connects all the cells then the poweroutput fall a little as cells become shaded.
I have 2 85w BP pannels one i connected the wrong way neg to pos etc and melted this "thing" it also acts as a protection incase you do what i did.

Now the one without looses power output very rapidly when shaded the other not-but i only use one

I cant remenber the namd but the "things about 1inch Xhalf inchX quater inch

Try calling bp and ask what this thing is if you like i can photograph it and send it to you??
 
If, as you say, you just want to keep the batteries up whilst the boat is idle for 6 months you won't need a large array. All you need is enough power going in to replace what the battery looses just by standing still. The size of the array needed depends on the size of your battery bank. Something around 10% of the AH of the battery will be more than enough (i.e. a 10 watt panel on a 100 AH battery).

I would second what others have said about Barden

PS There is an article in this October's PBO on solar cells which will answer most of your questions.
 
The 'thing' will be a diode available from various sources ie Maplin, RS etc.
Perhaps another formite could tell you the type required as I now have no component catalogues.

Iain

Iain
 
As Iain says, the 'thing' is a diode - preferably a Schottky diode as they have lower forward voltage drop. I had these discussions with Barden and Solara (head office in Germany) as they did not supply diodes and they argued that they are not required because the output voltage of the shaded panel will not be significantly lower and only a very tiny current would flow. I did not consider that to be the case for a yacht - fine for the roof of a building, perhaps, where there are no masts, but not a yacht. Edit:- So I bought diodes from RS and fitted them. Sorry, I don't have the details to hand.

Regarding shading, earlier I was really talking about diodes inside the panels which are not present on my Solaras and cannot be put in. This means that the shadow cast by the topping lift alone reduces the output of one of my panels from 8A to less than 2A. More shading and the output falls right off. This would be seriously bad news if you wanted the panels for trans-ocean sailing but in my case it is only essential for domestic load at anchor or moorings and I can always work around it.

The trouble is that these big panels are not easy to mount and to take them back is a major exercise. In any case, then you have to start all over again. That's why I decided to live with what I have and never use the same supplier again because they are either ignorant about their products or deliberately misleading.
 
They are ignorant.

I used panels from a company in the south of the UK, they were very good about free advice, and the price was right. The cables they supplied were of superb quality.
 
I use 4 rigid 75 watt panels, wired for 24 volts, I mounted them on the roof of the wheelhouse and they work well, when they get patially shaded, the output does drop, but I have them on wandering leads, so move them to a more suitable position. I now only need to run my genny for three hours every two days, and tiume that to be when folk are not sleeping in the anchorage or times when I would disturb them. I make water at the same time as genny running, so this works well. I only got the panels this year, but they work well, I'm very happy with them. By the way, we are a very power hungry boat!
 
I got mine through E bay, from a guy in germany, £210 each with a 12 volt controller, thats for a rigid 75watt panel, that's also cheap!
 
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