Solar The Solar Panel Thread
- Thread starter cruza driver
- Start date
I wonder when they will be available and at what cost. Great article and example of how power is lost/regained.
Hi @mikerezny , now look what we have started!! When all this is sorted out, we will all be "arm chair" experts. Still to check on diode type/s in my panels. Just as well you have checked what happens when your panel is shaded. Important if off grid for a while longer than you are now.
Attached are photos of Solar Panel Testing last week on which data was collected. In the back ground is my Penguin and tug taken at the same time in the Connondale Ranges. I will also put some other pictures in the other forum "what I did on the weekend" as soon as I can.
Attachments
Another great video on solar production. I had viewed this one before I did my testing. That is why my panels were NOT moved at all during testing. Because it was all done in about 20 minutes, there would not be too much change on sun direction. I could not guarantee consistent results if any panel was moved at all, as little possibility of getting same angle of panel to sun.
I thought I knew a bit about solar before reading some of this info.
Really interesting stuff on the series vs parallel, and cell shading.
I think I'll invest in a MPPT controller and keep them in parallel due to the high chance of shading on the roof mounted panels.
Hello @Bellbirdweb , you are not the only one who thought they knew a bit about Solar panels and charging. I was just interested in experimenting to see if improvements could be made in charging with an MPPT controller, instead of buying another battery to extend time off the grid. This is mainly what I do for up to a week or longer. As @Drover said "nothing like testing in real conditions instead of semi controlled in videos". Look what has happened! The solar thread has gone ballistic!! I was only the guinea pig with limited info. @mikerezny was the one that provided the "in depth" knowledge to properly interpret and analyse the raw data I was able to supply. @G Daddy was in there too. I believe nothing but good information and greater knowledge that will benefit all those interested in solar can come out of this thread. Thanks to everyone who followed this thread and for the interest and enthusiasm they have contributed. God bless.
I love it. Also being a tech I love playing with the stuff.
I've been playing with DC stuff since I was a kid, and work in computing and communications still.
I thought solar was pretty straight forward, so all of the info has been fantastic, keep it up.
Hi @Bellbirdweb , another "closet " techie coming out of the woodwork!! AHHA. You too are now on my list of very valuable friends to call upon when help is needed. Glad you like what is coming out of all this.
It's really a big pain as I have pulled my whole system down and put it back together, mostly upgrading the cabling and connections..............not pedantic enough to run a big test to see though................though after looking at your test it does pique my interest in seeing how my system fares but one on the roof and one on the ground wouldn't have the same picture quality as your solar farm @Boots in Action
I did almost the same .....but managed to redo the wiring on the old solar controller....and it now works so saved some $$$$.
also found some more anderson plugs, 6 and 8 wire that I thought I'd put in an unknown safe place, so deciding whether an anderson to a 12v socket is useful.
I might spend the $$ saved on a better voltmeter.
Decisions!
I'll leave the intricacies of solar performance to you lot. ..just let me know the answers when you get there.
also found some more anderson plugs, 6 and 8 wire that I thought I'd put in an unknown safe place, so deciding whether an anderson to a 12v socket is useful.
I might spend the $$ saved on a better voltmeter.
Decisions!
I'll leave the intricacies of solar performance to you lot. ..just let me know the answers when you get there.
Hi @Boots in Action Re panel spec, can you supply the IV curves for these panels, it seems the 200W panel is very inefficient.
Hi @G Daddy,
great job on the spreadsheet. I agree with you but also go as far as to say both the 180W (67%) AND 200W (55%) panels seem to be inefficient compared to the 80W panel (96%).
Hi @Boots in Action, did you manage to measure the solar input current when you did the measurements for each panel?
Something does not seem quite correct with the results of the individual tests.
cheers
Mike
Thanks for the chart @G Daddy , I believe you are correct in saying that the supposed 200 watt panel is not as efficient as the others. The surface area of the 200 watt panel is less than the 180 watt for a start, although the solar cells are supposed to be the latest in technology - advertising speak. Yes, I noticed the variation and was not impressed. Bought on Ebay for $195.00, the same people I bought from for the 180 watt panel more than 2 years ago for $279.00. Looks like I have not got what I thought although I think it said efficiency was 16.8% the same as most of the others at that time. Going to have a look at diodes tomorrow and see if they need to be upgraded to Schotky type. I checked with supplier when I first received it and they assured me it was capable of producing 10 A at peak light. I do not have the IV curves unfortunately, but I will follow up with supplier to see what they can provide for me. The other possibility could be the angle I had the panels placed. Perhaps they were not in the optimum position as the others as I did not have a protractor or similar with me. One variation I did not take into consideration in testing. I will be able to do more testing on this panel shortly and will let you know the outcome.
Hi @mikerezny , the only current readings were taken from the MPPT solar controller which I believe is current into battery after passing through the controller. Will need to do more testing again and get out my protractor next time and measure current before MPPT controller to see if efficiency is lost or not as good as it should be. Thanks for bringing to my attention so I can investigate more.
Hi @G Daddy,
is this the information that is on the certificate usually stuck on the back of the panel?
It is dark and cold now, so I am not going to go out to have a look.
cheers
Mike
Thanks @G Daddy , I try to walk away from this and your chart starts to lure me back and enticing me to do a run on my panels, I don't want to but feel myself getting sucked into this..................................you and flamin @Boots in Action are piqueing my interest into something that I really don't want to know, as if it's not up to speed I will want to spend $$$ rectifying it.........
Hello @Drover , my apologies for running so many tasty baits before you. I think I know you well enough by now that an older campaigner like yourself will know when to take the bait and hang on for a ride!! It is just a matter of time. I too have been taken in on what was my idea in the first place. It is just natural to make sure you have as much as possible at 100% efficiency. Isn't that why you rewired "Big Mal"?? It is only the thought of time and the effort that holds us back, and maybe the dollar value in expenses!! Cheers
An interesting read on basic solar- http://ecgllp.com/files/7014/0200/1304/5-Cells-Modules-and-Arrays.pdf