Flexible Solar solution ?

[MacMan]

We anchor a lot and currently rely on a petrol Genny to charge batteries at anchor. Whilst the Genny is actually fairly quiet (it's a Honda Eu10i) I would really like something that does not disturb the peace at anchor.

I am not really after a total solution - I accept we will still sometime need to run the Genny or top up under Engine but would like to extend the time we can spend at anchor without resorting to the noise.

We rarely "do" Marinas very often but have electricy on our home boatyard/pontoon.

One other feature I am keen on is portability - whilst I like my boat I don't think I will keep it in the "long long" term and am happy with any solutions which require little or no installation and can be taken with us to the next boat.

We have a Prout 33 cat - and therefore a massive (relatively) foredeck which can be used to temporarily "mount" panels.

A main energy consumer at Anchor is a old fridge which consumes 1.6/1.7A 24*7.
Currently have 220 AH domestic bank.

So as a quick and "portable" fix (but sadly not cheap) I am considering

Either

62w Global Solar P3 Folding Solar Panel with Cable Set

http://www.selectsolar.co.uk/pics/55W%20folding.php

Or 3

Unisolar / Spectraflex 32 watt flexible solar panel
http://midsummerenergy.co.uk/buy_solar_p...lar_panel.html

And I believe I need a charge controller

I am thinking

The morningstar - MPPT type has been recommended on the forum before.
http://midsummerenergy.co.uk/buy_solar_p..._regulator.html
Can anyone suggest/recommend a better way of doing this. Better cheap flexible panels/controllers? Wind I am trying to avoid as we have little space left at the back of our Canoe sterns and it would not be readily portable.

Replacing the frige is also on my long term list.

The neat thing about this setup is that it could all be rolled away when in Marinas or only an overnight hop when not required.

 

[srp]

I've got a Unisolar panel, but it's a smaller one than you have in mind. Now about 6 years old and still does a good job of keeping my battery topped up. I bought it because it can be walked on, and it's lashed to the forehatch. I seem to remember that this panel was sold with various brand names at various prices so I shopped around and saved a few bob.
I don't know enough about controllers to make a judgement - I bought a very cheap one, but (as I understand it) it may be worth paying more to get one which gives you as little electrical loss as possible.

 

[LORDNELSON]

I was just about to compose a post very similar to yours! We have home port electricity and anchor quite a lot, no generator and a small frig (Isotherm compact classic). So far we have not run down our batteries too far but I would like to top them up from a solar cell that can be moved around to obtain maximum output but put below when not required. I think a 20 watt PV cell would suit me and wonder about the (Photovoltaic module Aurinco Bluewater™ 12V 20 watt, Model PVBW020A00,www.aurinco.com/pvbw020_gb.html); not very flexible but long and thin so could go under a berth when not required. Grateful if anyone has experience of this make.

 

[npf1]

FWIW, I tried a 48W version of the Global folding solar a couple of years ago alongside a 32W flexible Unisolar. If I recall correctly (I posted a thread on here at the time), it was a cloudy but very bright day and, with the panels angled to the sun, the Global Solar panel was putting 1.6A into the battery (12V) whilst the Unisolar was putting in 3.5A. We then tried another Global Solar 48W panel, assuming the first was not working correctly, and that also put in 1.6A. We ‘concluded’ that this was either due to different technologies and that the Unisolar was more suitable for northern climes (as claimed in their blurb) or becuase the Unisolar panels output more than their rated output for the first few months (per the instructions).

If you are seriously considering spending big £ on panels, ask the dealer for a demo of the different contenders working side by side.

Unless you’re planning to leave the boat unattended for days on end, you can probably do without the controller.

BTW: I eventually bought two of the much cheaper 64W rigid Unisolar panels, which are actually somewhat flexible without the aluminum frame, and often see them putting in 7A despite being installed horizontally and partially shaded by the boom. They also manage to put in a small amount (1.5A ish) on dullish winter days.

 

[MacMan]

[ QUOTE ]
We ‘concluded’ that this was either due to different technologies and that the Unisolar was more suitable for northern climes (as claimed in their blurb) or becuase the Unisolar panels output more than their rated output for the first few months (per the instructions).


[/ QUOTE ]

I am confused by this - you mean they are better than rated for a little why from new but then presumably fall off (towards their rated value) a few months from new. Intrigued to understand the physical process behind this if anyone knows.

did the Unisolar panle still "beat" the Global Solar ones after "a few months?

 

[npf1]

The Unisolar's documentation states output will drop by up to 20% (at least I think it was 20%) after a few months. That being said, after two years I have not noticed any drop off on the two Unisolar panels I installed.

The Global solar ones went back to the dealer after I'd tried them as their output was pathetic, so I've no idea how they go long term.

 

[npf1]

These might be worth tracking down: http://www.uni-solar.com/interior.asp?id=102

Maybe some caravan, motorhome or narrowboat accessories suppliers sell them in the UK. Or buy in the USA and get it shipped over.

 

[alan]

If you have loads of space on the foredeck, why not go for rigid panels:
- more efficient
- cheaper
You could mount it/them on some sort of frame so that you dont have to leave lots of screw holes when you eventually dismount them.
Kyocera were good value the last time I looked.
BTW, I have one Solara flexible panel which I leave permanently mounted, and in addition have two rigid panels which I mount on the guard rails when cruising (I leave the cabling in place and connect using waterproof plug/sockets).

 

[jeremyshaw]

Just to add to the previous posts a couple of things to consider.

1. How will you fix these do the deck? The Unisolar has nice eyelets so it can be lashed down - don't know about the Geosolar. Obviously you want to avoid fixings that will be a trip hazard.

2. It's quits a way from the foredeck of a Prout to the battery bank, so remember to allow for voltage drop.

FWIW you would probably get a lot more input from a windgen. My two 42w panels put in about 8amps here in the Caribbean - for about 8 hours a day. The KISS windgen obviously depends on the wind conditions, but rarely puts in less than that as a daily equivalent, and often much more. With a decent windgen you might never need to run your genset.

 

[AngusMcDoon]

I've got a Unisolar one. Seems to do the job. It's amorphous, which means that output per unit area is not as high as some other types, but advantages are...

- not bothered by small shadows much
- still works under a cloudy sky
- lightweight
- bendy, so can be lashed to curvy things like furled mainsail
- tough as old boots, won't crack or break
- won't damage your foot or deck or itself if you drop it
- thin, store it under a berth cushion

Mine is the 30W one. I get 1.8A in UK sunshine.

 

[AngusMcDoon]

Unisolar/Spectraflex 32W £24 cheaper here...

Clickeeee....

 

[wotayottie]

Oddly enough I have a Unisolar panel and once had a Prout 33 cat. Used to put the panel on the side deck or on top of the hard top. Wouldnt say it was a roaring success - I cant remember the precise details but the 35 watts is a rating in full summer sunlight and into a 12v battery - 3 amps. If you take an average over 24 hours you dont get anything like 3x24 amp hours or even 3x12. So it wont make up for what your fridge uses.

Cant see solar panels being any practical use in the UK except to keep trickle charging the batteries.

 

[Twister_Ken]

Sounds like replacing the fridge should be your first priority. Or, cheaper, adding more insulation.