Thread: How do you know what is a good solar panel.

I buy second hand panels - There’s plenty out there and the bulk sellers have no problems if you roll up with a multi meter on a sunny day and rat through a pile and test them as you go - at least you can check the actual current flow on them (by shorting them out with the current setting on your multimeter) and checking that against the data plate on it. If I get 90% or more of the plate rating I’ll take it. Bought 600 watts for the motorhome for $100 recently.

Had second hand panels on my caravan too which have been great.

At least I’m not much out of pocket should one crap itself.

Personally I have found that the flexible panels are crap, Probably due to the fact that they have no air circulation and get too hot.
Mounted correctly the ridged panels are a FAR better option

Old flatmate in the usa is a keen longtime off roader and rates these guys panels for longevity.
Rv & Overland | Merlin Solar

Agree with Trout that flexible panels seem less efficient that fixed panels, in my limited experience.
However, there is a wide range of performance and the only real way to tell is to test them.
It can pay to buy through a credible business with shop front stores since their reputation is on the line and they're more likely to look after you if the panel is a dud.
Monocrystalline (look for the diamonds) tend to be more efficient than polycrystalline. See explanation below.
I was surprised that some Aldi panels I bought on impulse turned out to be quite good. Jaycar panels also seem good.
10 amps from 200 watts is not bad. Best I've seen is about 12 amps in ideal conditions.
Generally though, you get what you pay for.
It's important to manage your freezer to avoid unnecessary current draw. When on 240 volts I turn the freezer down to about minus 15 to freeze it solid. Then on 12 volts it is only necessary to run the freezer at about minus 4 to keep it frozen.


Solar Panels - Which technology type is best? | Solar Quotes

Hi Phillip,

I can answer this as I found a very very reputable seller, bought one of their panels and they are certainly up to spec based on real world usage.

Seller is Off the Grid Solar Systems - Specialists in Off Grid Power Systems

I was looking for a lightweight flexible ( non folding ) panel that would fit stored in the passenger side of the cargo barrier in my d2.

Bought this one: Sunman eArc 100W - Semi Flexible Lightweight Solar Panel - SMF100S-4x09UW
It’s a perfect fit stored on the cargo barrier inside, so takes up no roof space when on the move. I just clip it to the side of the D2 or on the windscreen when camping.

When tested ( in autumn) I achieved the full 100w using a Victron MPPT regulator.

This brand is one of the very few flexible panels that are on the CEC approved list so according to the sales bloke get randomly tested by CEC to check they’re up to spec.

I have no affiliation with this business - just found them in Melb and had a chat abd they sell good gear.

Thanks for that. You have provided a valuable insight into true vs BS output claims.

I looked at the site you mentioned and found an Enerdrive folding solar panel with the dimensions 2015x750 and rated at 250W. I assume that this is an accurate rating as it is about 1.5square metres.

It is interesting that there are several sellers on ebay selling similar looking folding panels with a smaller dimension of 2215x545 or 1.2 square metres as a 350watt panel.

There is no way that the panels could be 350watt however if they are a true 200watt panel they are suitable for me as they should yield about 13.5+ amps.( vs about 6.5 from my current very heavy panel)

The big problem is that the Enerdrive panel is $749 vs $235 for the slightly smaller panel and $749 is out of my price range..

I cannot use a flexible panel as it would interfere with my fridge, if placed across the rear seat and I now have room for the multifold panel as I have graduated from a camper trailer to a caravan.( that is if I ever get away after now postponing and rebooking 2 times because of Covid shutdown.)
Regards PhilipA

A interesting Aussie Youtube video comparing cheap and expensive flexible panels.

Cheap VS Expensive Solar Panels | 12v Touring | Project Cyan - YouTube

Garry

Originally Posted by 101RRS

A interesting Aussie Youtube video comparing cheap and expensive flexible panels.

Cheap VS Expensive Solar Panels | 12v Touring | Project Cyan - YouTube

Garry

Enjoyed following Seek Adventure…..he’s stepped back from his channel which is a shame.

Although my experience is semi flex are not designed to constantly flex, I think they are designed to flex to curve they are being mounted to once.