Solar panel

[bromleybysea]

I'm about to move out of the marina and will be cruising and probably on a swinging mooring eventually. I was thinking of getting a solar panel to supplement the alternator and to keep the batteries (180ah) topped up when not aboard. I think the most practical solution would be a panel on a wandering lead that I can position to best advantage when at anchor or on a mooring and which can either be stowed or tied to the top of the dinghy on deck or elsewhere as suits. I don't have anywhere that's not shadowed for some of the time. Trouble is, there seems to be a bewildering choice of type- though my requirements I think suggest a semi-flexible type with grommets in the corners- and of price and supplier. Some of the ones on ebay seem a bit dodgy to say the least. any advice chaps, on any of this gratefully received!

 

[Bobc]

I recently bought a 100w semi-flexible panel and regulator on ebay, and I'm really pleased with it (we moved from a marina to river mooring). The panel has holes in the corners and a 5m flylead, and I put a socket in the cockpit to plug it into, so can move it around the boat as necessary.

The panel was £140 and the regulator was about £30 (I got a dual battery one, so it look after both battery banks).

If you have the space, go for the biggest panel you can.

I've got this panel http://www.ebay.co.uk/itm/100w-12v-Semi-Flexible-Panel-with-Worlds-Highest-Efficiency-Sunpower-Solar-Cells-/271923905522?pt=LH_DefaultDomain_3&hash=item3f4fed83f2

and this regulator http://www.ebay.co.uk/itm/EP-Solar-10A-12-24v-Dual-Battery-Solar-Charge-Controller-/271925273659

If you go for a bigger panel, you'll need a 20A regulator.

Hope that helps

Bob

PS. At anchor, it adds to the battery during the day even with the fridge running. If I were cruising, I'd go for the 150w one though.

 

[macd]

My experience with flexible panels (of three or four makes) isn't good. All degraded badly, typically dying just after the warranty expired. Some of these, but not all, spent part of their life in the Med sun, which seems especially harsh on them.
Rigid panels, on the other hand, seem to go on for ever. I appreciate, of course, that they're more cumbersome and often more troublesome to fit.

 

[ghostlymoron]

Put a semi flex permanently mounted in a convenient position. Don't worry about some shading. What's the point of having a panel that's only generating when you are on board to deploy it. The sun shines whether you're there or not and its nice to board, check batteries and find their full. I have a cheap PMW controller but the MPP are more efficient (but more costly). For 180ahr capacity I would go for 50w panel (min) or much more if you have a fridge. Strong sunlight is rare in the UK at the moment but you get useful output even with some cloud cover.

 

[Stemar]

You do get a lot more bang for your buck (punch for your pound?) with rigid panels. A gallery over the stern could provide an unshaded area for mounting, with the bonus of somewhere to attach a cockpit tent but, if that isn't practical, get two or more panels. One shaded 50w panel and one in the sun will give more output than 100w panel with a small shadow across it. That's how I solved the issue on Jissel. Two 20w panels on the hatch garage keep the batteries topped up and, last month, even allowed us to run the cold box enough to keep things cool, if not cold.

You may not get as many amps as a temporary panel in full sun, but you'll get a lot more amp hours because fixed panels are doing their stuff whether you're there to move the panel chasing the sun or not.

 

[dsw]

I have a 4 amp solid folding type which I got from maplin £15 on offer a while ago which keeps my 12v bank 2x120ah topped
up no problem . and when you look for one don't just go by how many watts it is as it is the AMPS that are important.

 

[mattnj]

don't just go by how many watts it is as it is the AMPS that are important.

 

[ghostlymoron]

You may not get as many amps as a temporary panel in full sun, but you'll get a lot more amp hours because fixed panels are doing their stuff whether you're there to move the panel chasing the sun or not.

Quite so.

 

[TQA]

I would avoid flexible panels due to their short life.

A fixed panel from from a reputable maker like Kyocera is a good investment although I believe the smallest they do now is 140 watts. You might find a used one from someone going larger.

My Kyoceras are 8 years old and still working well.

 

[Laurie]

I wont pretend to be any electrical whiz bang, but I have 2x 85ah batteries fed by 2 x 20 w semi flexible panels on the coach roof, fed via a 10amp dual bank programmable controller. I can't remember the last time I used a mains charger. For week end sailing and holidays it keeps everything healthy. I have also taken steps to limit consumption though, and one of the simplest and most effective is changing to LED lighting, as many have now done, or the lovely oil lamp!

 

[Champagne Murphy]

http://www.pennygreenfingers.net/60w80w100w-semi-flexible-solar-panels.aspx
I found these useful and affordable. As a previous poster said, don't worry about a bit of shading. You'll need a regulator though. Semi flexible wins over roll ups every time I think.

 

[macd]

me, too, but with a bit of this, as well: :ambivalence:

 

[CAPTAIN FANTASTIC]

Six months ago I replaced my Rutland 913 with a 100w semi-flexible polycrystalline solar panel; I bought it from ebay for £100. Overall, It charges my 4 x 110 amp batteries without a problem and fits nicely between mast and main hatch. There two types of solar panels; monocrystalline and polycrystalline. Monocrystalline panels are slightly more efficient but do not tolerate any shade and it will stop delivering amps altogether, however, the polycrystalline panels will carry on producing power, at a reduced level, even when partly under shade. Solar technology has improved in the last 5 years and my intention is to install one more solar panel on the boat.

 

[William_H]

The OP does not say just how much current or power he thinks he needs from the solar panel. I would think 10 watts per battery would go a long way towards keeping the battery topped up while he is away. It will however be almost useless for replacing battery use while you are on board.
If you decide on a small panel then it might be OK 10 watts (or less) without a regulator. In which case temporary mounting can be fairly easy. I bungee mine onto the top of the boom cover. Don't be too afraid of the Chinese offering. Price is generally good and in fact many panels are Chinese made now anyway.
good luck olewill

 

[Binman]

Good mounting place William, my small one came with a diode, best not under the boom, mine is laid down in the cockpit out the way of preying eyes on a trot mooring, in front of the mast I think would be a good position?

 

[ghostlymoron]

Don't you find it awkward on the cockpit floor when you're sailing?

Good mounting place William, my small one came with a diode, best not under the boom, mine is laid down in the cockpit out the way of preying eyes on a trot mooring, in front of the mast I think would be a good position?

 

[Binman]

No it's only there when moored.

 

[ghostlymoron]

In which case, you're missing out on an awful lot of potential charging. I can't see the point in having a panel that's not charging whenever it can. But...... each to their own.