Solar panel problem

[raymo]

Seeing Alex's thread prompted me to look here for help.
I have bought an old caravan that has a seemingly just as old solar setup.
My problem is that it only puts out 2.5 to 2.8 amps on a sunny day, and I don't know what it should put out because it is screwed down to the roof,
and has no visible specs plate, and no info came with the van. Is there any
way I can find out how many watts the panel is. It is 900x 400 approx.
raymo

[xelasnave]

Probably 85 watts.
Alex

[pmrid (Peter)]

Originally Posted by raymo

Seeing Alex's thread prompted me to look here for help.
I have bought an old caravan that has a seemingly just as old solar setup.
My problem is that it only puts out 2.5 to 2.8 amps on a sunny day, and I don't know what it should put out because it is screwed down to the roof,
and has no visible specs plate, and no info came with the van. Is there any
way I can find out how many watts the panel is. It is 900x 400 approx.
raymo

G'day. Because the caravan/solar rig is pretty old, my guess is that the panels are unlikely to be more than 100 watts each. That's what was probably considered top of the line back in the day. Today, an average Van setup will be in the range of 300 watts or so in total. That's usually enough when coupled with deep cycle batteries, a good inverter and the new generation of high efficiency appliances. The older style of van fridge were terribly power hungry.

In view of the relatively low cost of new panels these days, I'd be inclined to suggest replacing your oldies entirely since they are undoubtedly working well below their rated capacity in any case.

Peter

[xelasnave]

Have a look around here. The best in the business.
https://www.rpc.com.au/?gclid=CjwKCA...BoCFXsQAvD_BwE

Alex

[raymo]

Thanks fellas; there is only one panel, so if 100w it is not doing too badly for probably 15 or 20yrs. It is incorrectly fitted flush with the roof[no air space], so it will be a pain in the derriere removing all the sealant.
raymo

[xelasnave]

Perpahs just leave it there. I have one old panel ..my first..purchased in 1996 and it still works to keep a 100 amp battery charged.
I like multiple systems. So even an old battery and panel can be used to run a shed light that you don't use too often. An important part of any solar set up is your Genny and charger..a small Genny is all you need and Bunnings usually have a four stroke of about 750 watts that is easy to start and has smart power...it revs higher or lower depending on load...also remember you charge at 10% ...they also have a key start Genny ..my last was about $800 that is 2000 watts ..worth every cent for the key start.
Read what Rainbow says about stuff and give them a ring for a chat..they grew up in the Hippy capital and really do know their stuff ...they supply all over the Pacific Ocean as well as just me.
Alex

[raymo]

Hi Alex, yes, I might just add a 120w panel in parallel giving a total of
about 9 amps; that way I won't have to bother replacing the regulator
which is stuck in an awkward place to get at. I already have a 750w GMC generator which I bought nearly 10 yrs ago for $99.
raymo

[xelasnave]

Good plan Raymo.
I recently purchased one of those fold up panels at jcar and thought at $250 odd it was horribly expensive..but I was trying to get an exchange on something that they could have backed off from...anyways an interesting story which I will devote a chapter to in my book..but it is an absolutely fantastic product..it has a great little regulator built in decent leads sensible legs ..just everything so well thought out...the thing I liked and to watch out for is it was all there..so easy to by a panel then there is the regulator and the leads the clips etc and it's that small stuff that really adds to the cost.
The refrigeration is the thing to watch..best to forget keeping raw meat..cook your meat and run the fridge just during the day.
Alex

[glend (Glen)]

Personally I would scrap it and install a new panel. Those things have a limited life span, most new panel manufacturers today only warrant them for 12 years, and will likely adversely affect the new panel if you add one to the system, in the same way an old battery can hold down a new one when connected to a bank. Even a great crystaline panel will lose 1% of its effeicency each year, film panels only last 2-5 years.. Btw all panels usually have a sticker on the rear that describe the rated output.

[raymo]

All good advice Alex and Glen, thank you.
raymo

[AndyG (Andy)]

Hello Raymo,

If money is an issue (I can relate, if so), consider the following:
Many home solar installers get custody of used panels from roofs, in the event of warranty claims. If a few panels go, they often replace the whole string (charging it to the panel manufacturer). They do this in cases where new stock doesn't match spec sufficiently. You can see that the remaining panels have nothing wrong with them, aside from being a few years old.

The Solar installers leave these panels out the front of their shop, and the public can take them away. This saves the shop having to pay disposal costs. If you can find such a shop, you could save some dough. I've picked up 22 panels this year through the above means.

Also, Solar shops buy panels by the pallet load. Often they will have 1 or 2 left, which does not match the next 30 panels they buy on the next load. Some shops sell these new, orphaned panels at cost. Our local Astro club bought 2 new 300w Mono panels for $70 this way.

If you weren't located on the other side of the country I'd give you some. As mentioned, just check that the Max voltage matches your intended regulator/inverter, etc. Perhaps money saved on panels could get a new inverter if needed.

[raymo]

thanks Andy, I'll see if the local shops do that.
raymo