Buying solar panels on Ebay is a massive gamble. Almost all sellers advertise panels that can't possibly achieve the stated output.
I was about to post a deal, but after having written the below found out that I can't post it because it's not a top rated seller. Since the text has the intention of helping anyone buying solar panels on Ebay to avoid being cheated as well as highlighting one very good current deal I decided to make this forum post.
Using the current 10% off you can get:
200W 12V Solar Panel, 1 for $88.20, 2 for $167.58, free delivery
here
This 200W panel appears to be the real deal. At this price it is a steal.
Simple novice guide on how to check whether a solar panel can live up to the wattage given in the description: calculate the area in m2 and multiply by 160.
In this case: 1.58m x 0.808m * 160 = 204. This most likely is a genuine 200W panel.
To explain the calculation: panels are rated at a standardised insolation of 1000W/m2. Cells used by most manufacturers achieve about 18% efficiency. The area covered by cells (as opposed to gaps and frame) is about 90% of the total area, giving panel efficiencies of about 16%. A bit less for small panels where the frame takes up relatively more space, a smidgeon more for very large panels where the frame takes up relatively less space.
There are a couple of exceptions where manufacturers achieve higher efficiencies, even slightly over 20%, SunPower in particular, but they won't be found anywhere near this price point. Don't be fooled.
The same listing contains a 300W panel with the same dimensions, it most likely is a mis-labelled 200W panel. In a different listing the same seller advertises a 200W panel with dimensions 1.48m x 0.68m, that most likely is a mis-labelled 160W panel.
Be careful what you buy. When you receive it you might want to check the outside dimensions of the box to make sure it can actually fit a panel of the advertised size.
Thanks for the information!
It seems like an great price for the size, especially after the discount. Even second-hand house panels often go for $30-40 on Gumtree (though sometimes free), but this should make buying a compatible MPPT solar charge controller a little easier.
Have you seen any great deals on batteries? I've seen a few second-hand deep-cycle lead-acid AGM batteries on Gumtree that are sold when they reach their 2 year compulsory replacement, but I don't think they've been tested for actual current Ah ratings.
I haven't really looked into fuse boxes or inverters though. I'm little worried about drilling random holes in my van's roof.