Solar Panels

[stardust]

My boat a Bavaria 38 is based in the western Med and I'm finally going to bite the bullet and fit a couple of solar panels ,keeping the fridge  and a waeco  box running is using about 70 amps  per day. We have a very strong Bimini fitted which stays up all summer,The question is where to fit them
I would be grateful to hear from anyone who has fitted solar panels to a similar boat
Bill F " Stardust"

[Nigel]

using about 70 amps  per day...

I assume you mean 70Ah per day, which is about 3A. You should roughly quadruple this to size the panel (to allow for night, shading, charge efficiency ...) so 150W or more.

[Stuart]

Hi Bill

I can't help you with the installation on the Bimini as we installed an arch but we have 340 Watts of solar panels keeping the top loader fridge and a portable Engel freezer running.We have been able to anchor for up to a month, without starting the engine or the Honda generator.
We also have a KISS wind generator which helps but is not as reliable as the solar panels as far as input to the batteries.

[Ethel]

Bill,
We have an older (1993) Bavaria 350.  I fitted a 70W panel over the main hatch garage three years ago. The 70W panel was the largest which would fit the space.  Nowadays you could probably get a higher power panel with the same dimensions. The panel is on a frame which can be tilted to optimise solar capture, but unless your boat is in a fixed orientation (on a pontoon or tied up to a quay) there is no real value.  The panel does not adversely affect visibility in the saloon (could actually be an advantage in sunny climes). 

There is potentially an issue with shading of the panel by the boom reducing the panel output, but I have found that the panel keeps the batteries topped up year round. Admittedly I am not running the fridge continuously.

[stardust]

Thanks for the input .Ive more or less decided on 2 x 125W panels on an arch behind the Bimini
Bill

[DarnellFord]

My boat a Bavaria 38 is based in the western Med and I'm finally going to bite the bullet and fit a couple of solar panels ,keeping the fridge  and a waeco  box running is using about 70 amps  per day. We have a very strong Bimini fitted which stays up all summer,The question is where to fit them
I would be grateful to hear from anyone who has fitted solar panels to a similar boat
Bill F " Stardust"

I am really not sure about these panels.. These panels are very expensive with little efficiency so I am still not using them.

[sailaway]

Hey, we have a Bavaria 36 (2005) and we installed a 200 Watt solarpanel before our 2 years cruise (Norway - Greece - Norway)
It worked great and we was self-sufficient with power. Just make sure you buy and install a MTTP controller, this gives you more power out. I have a site with our installation step by step, its in Norwegian, but with Google translate and alot of pictures i think youre good. The site is; https://breddegrad.no/solcellepanel/

Kim

[Impavidus]

Hi. We fitted 2 flexible solar panels last summer. 100 watt each with a charge controller. They were less than £100 each from eBay. 20 Amp controller was £15 or so. Bright sun gives us 10 A/h. when no shadows. Even in the last few weeks we have put them out on top of our Bimini and we are getting 2-4 Amps depending on the brightness of the sky. Keep the cable runs as short as possible and use good thick cable with the IP65 quick release sockets. they are on eBay too.

Hope this helps.   

Ant.

[Marchi]

I done this last spring on BAV 36, just adding one more element to bimini and for stability use the frame of solar pannel it self.

2x100W, 2x5,6kg,
horizontal rotation
Cabel to regulator 4mm2
Y conector  ++ / --
Regulator Tracer Mppt 20A


Like this


or like this


nonvisible




Conector Y


Just added one more element to bimini construction




Rotation variants. The small one on the left just work great.

[Craig]

Do you really need a large bank 0f solar panels to provide all your power indefinitely?

We found that in the Med, unless you are going to anchor in a bay ( rare in Greece or Turkey) for 4 days or longer without moving, 400amp/hr batteries and 120w of solar panels would be OK. Shore Power and the amount of motoring you are likely to be doing should supply most of your needs.

We fitted 120 watt semi-flexible panels to the cabin top, just in front of the cockpit to our Bav 38. They could be walked upon and worked well when partially in shadow from the boom. We would typically sit in a bay for 4 days before batteries were down to 1/2 charge.

120 watt semi flexible panels are much easier to install just in front of the cockpit than installing frames and arches and a lot cheaper. We also saw a number of solar panels ripped off when tangled in the rigging of boats mooring next to the solar panels built over the bimini.

Craig
"Shirley Valentine"
Gold Coast
Australia

[Salty]

...........We fitted 120 watt semi-flexible panels to the cabin top, just in front of the cockpit to our Bav 38. They could be walked upon and worked well when partially in shadow from the boom. We would typically sit in a bay for 4 days before batteries were down to 1/2 charge.

120 watt semi flexible panels are much easier to install just in front of the cockpit.........

Craig
"Shirley Valentine"
Gold Coast
Australia

Craig, have you got any pictures showing exactly where the panels were mounted, also it would be handy to know what the dimensions of your panels are.
Thanks.

[Craig]

Salty,

A couple of photos attached. Excuse the mess with the lines.

I have 3 X 145amp/hr house batteries and with the current trickled in from the panels could last 4 days at anchor  in summer in the Med before voltage dropped to 12.2 v.

My power usage would be similar to most sailors. The refrigerator would use nearly 90% of the power even though I have a TV and a microwave.

You will note that I have left grubby footprints on the panels. The panels were the largest size I could fit in the space.

[Salty]

Thanks Craig, I have a B36/2002, and I was curious how you managed to fit 120 watts of pv panels in that area. It's that full width cover you have for the hatch garage that makes the difference. On my boat the garage only just covers the hatch, while on yours it appears to extend across the full width of the cabin roof, thereby allowing more space. I fitted a 100 watt panel which was marginally too big for the hatch garage, and so I have to be careful not to step on the edge of it, or allow any slack in the ropes passing near to it. So currently I'm getting an "A" frame made up to fit my one panel plus a second one, and while its costing more than I want to spend, it will leave a facility for other uses.

[Marchi]

It's all about calculation of Ah.
As you said 400Ah acc and 120W solar should be enough for staying in anchor for up to 4 days, with motor runing 1-2h per day it'll expand your stay for some day.

300-400Ah accu or more and solar 200W+ will give you independance all the time.

Let say you're sailing 6-8h per day using autopilot and motoring only when you're comming or going to/from anchorage. Also running refridgerator and all instruments all the time and other electronics also.
Sum Ah of all electronics on mid cruser, like ours, would give you aprox. 100+Ah per day and only 120W solar pannel would be slightly underpowered (enough for 3-4 days not more).

"Suckig" accus too much will shorten their lifetime. Some die after 3 years. With good solar support will last 10 or even more years.

One more important aspect is shadowed panels, which could reduce their effectiveness to less than 20% of their nominated capacity. Yes, one rope or boom/mast etc. shadowing one cell will reduce power to all pannel. 

p.s. Sorry for my english.

[Craig]

Marchi,

Your calculations are correct, except that the power output of the flexible panels I have fitted do not drop to the level of the mono-crystalline panels that are often put in the fixed panels. If I have 20% shade, the power output is reduced by about 20%, not 80% like many of the fixed panels.

During the 5 1/2 years we spent on the boat in the Mediterranean there was a lot of motoring and only rarely did we anchor without our batteries being full. Most of our friends had similar experiences. Many of the Med sailors really didn't need solar panels and as mentioned, they are a pain when Med Mooring and we have seen many bent arches and ripped off solar panels.

If you are anchoring for longer than 4 days at a time, sailing a lot, particularly using chart-plotters and autohelm, I agree, you will need a generator or more solar panels than I have fitted.

Now that we are back in OZ, have our own shore power and do only occasional long sails, our solar panels are basically useless. I will take a generator on long trips as we can often anchor without any neighbours to annoy.
Craig
"Shirley Valentine"
Gold Coast
Australia

 

[Marchi]

@Craig
The engineers told me that monocrystals gives more power, lasts longer and work well also in bad weather (no sun), from early morning to last lux from the sky in the evening. Minus is that they radicaly lower output when they're shadowed.

We talk about different concept of cruising. In Adriatic, specialy Croatia, there are a lot of verry protected bays on islands and verry crowdy marinas in cities so my concept is daily sailing from one island to another and sleeping on anchor under the stars as long as possibe.  

And of course no generators involved   

My college Jasmin sailed Atlantic this december on Bav 34, solo, with 150W solar pannel. Autopilot was the only partner.  He ran motor here and there for filing the accus enough. He told that a little bit more solar W would be nice to have. Needs 15 days from Cape Verdes to Barbados.

Marko
"Klara"
Villaggio del pescatore - Duino
Italy

[aquapore]

Tip for solar panel.

We are installing a 240 watt 24 volt panel of the type used for household roofs and coupling it with a MPPT controller to charge the 12 volt system.

24 volt panels are dirt cheap - I paid $130 (AUS) from local supplier of domestic off grid systems.
The MPPT controller cost $65.

More importantly. using 24volt panels with MPPT controller allows a greater proportion of available solar energy can be harnessed particularly on cloudy days.

Hope this is useful

Regards

Aquapore