solar panels

[Johnjo]

Hi
Thinking about buying a solar panel for next summer, Seen some advertised in P.B.O mag, 15w battery saver pro.& 100 with a regulator,which appears to be a good price,does anyone have this type fitted on their boat? If so are they any good?
How many amps could I realisticly expect it to produce a day?
When they say 15w, is that max per hour? if so,how many watts to a amp?
Time to start dropping big hints to hwmbo on what to buy for xmas!

Mike

 

[halcyon]

Volts x amps = watts.

But allowing for efficiency, and cable losses say 15 watt = 1 amp.


Brian

 

[colin_jones]

These ratings are about right.

For several years, I have used a couple of 30w flexible panels. They are rated 1.9A, but give about 1.5A in good sun and a bit less on cloudy days.

We have not mounted them on the coach roof of the motor sailer, (they like a bit of air around them) but keep them on strings so that (a) we can always turn them for best angle to the sun (b) we can put them out of sight when the boat is unoccupied. They are light and thin, so no problem to stow.

They are currently mentioned on the colvicwatson.co.uk website.

 

[Guest]

I bought a solar panel from a add-mag in a Sunday paper that is for keeping a battery topped up for £20 and it has done just that. I have a heavy duty car battery that is removed from boat over winter and the pannel is placed in the West facing spare room ( AKA boat shed ). Throughout the season it lives by the stb`d window and does a good job in both situations.

 

[ccscott49]

It totally depends on how big (Amp Hours), your battery bank is whether this panel will do the job, so basically I need more info to be of any use to you. But don't expect much from a 15w panel in the UK.

 

[bedouin]

If you delve deep into the manufacturers websites you will find graphs showing typical performance of the panels at various latitudes (in terms of Ah/day). I would guess that at the height of summer you might get about 5Ah/day from a 15W panel.

 

[byron]

The way my hair is going over the past few years I will soon be able to use my bonts as a Solar Panel /forums/images/icons/crazy.gif

<font color=red> ô¿ô</font color=red>
<A target="_blank" HREF=http://www.freeware.mcmail.com/435.htm>http://www.freeware.mcmail.com/435.htm</A>[/b]

 

[ccscott49]

As long as it's always pointing at the sun you might, if you're really lucky.

 

[Johnjo]

Cescott
have two 90amp batts, one for starting another for domestics,in the ad I read it said possible to connect 3 panels together,making 45 watts,Ihave a 35amp alterator fitted with a smart regulator,so basically the panel is for the domestic side,but really only want to fit one panel,

Thanks everyone for the info,great help.

mike

 

[ccscott49]

I would get two. You see them advertised on Ebay.co.uk, they may be cheaper there.

 

[Danthegorrila]

15watt /12volts =1.3 amps ish in good conditions. The pannels should be straight inline with the sun any shade over the pannel will stop a cell working. They all produce a standard charge and you need them all to be working to increase the voltage to anything over 13 volts that you need to charge batteries. This really means get a 40 cell panel rather than a 36 cell panel.

Of course it depends what you want to do with it, if it is just keeping the batteries full while your not on the boat almost anything will help, but for other use it is very complex. Nigel Calders books have great bits in them about panels.


PB

 

[Guest]

Hey Mike, I noticed you used the acronym 'hwmbo'. I personally have a 'swmbo', is there something you aren't telling us?

 

[Johnjo]

DEFINETLY NOT.
Just a slip of the finger,More to the point.why are you so interested?

MIKE

 

[ccscott49]

S is a long way from H on my keyboard, some slip! /forums/images/icons/wink.gif

 

[JerryHawkins]

It\'s obvious...

I just assumed that the H stood for HER !

Cheers,

Jerry

 

[Guest]

Nice comeback but alas it won't work. But I wouldn't call four keys across the keyboard a slip, I'd say it was a closet issue you need to talk to someone about

Cheers

More beer.......

 

[BrendanS]

Now look here dear chap.Your attitude is not one which is required of such an august establishment.

Sheep sha**ing, cattle rustling, disease ridden Aussies have no cause to cast aspersions far and wide.

I don't have a criminal record, can I come visit /forums/images/icons/cool.gif

PS I'm Welsh, so the sheep sh**ging is meant as a compliment! <g>

 

[Johnjo]

Well thats that then! secrets out,Strange thing is,did not realise was that way inclined,still never to late to learn! Just hope that SHE HMBO do's not read this, Could end up being a right pain in the arse.

mike

 

[Johnjo]

Thats the problem with slippy fingers,
they don't know when to stop!

mike

 

[MedMan]

Just remember the girl down the road - Ivy Watts. i is the symbol for amps and v is the symbol for volts giving the formula i x v = watts

We have 4 x 30W panels giving us 120W in total. In theory, one might expect 10 amps from this system, but only at noon on the equator on mid-summers day with a perfectly clear sky and a pollution-free atmosphere. In practice, in the Med, the most I have ever recorded is just over 6 amps.

In June, when the sun is getting high in the sky but the water has not really warmed up (our fridge is water cooled) we are self-sufficient on the electrical front and can remain at anchor until something else runs out. However, by August, when the water reaches 25 deg C or more, the fridge demands far more and we can only keep going for about three to four days. Still, three days without running the nasty, noisy, oily beast we keep in the cave below is far better than one!

David Teall