Time to start looking at solar.
so got up on the roof yesterday and measured everything up. so what I end up with is basicly 4 spots I can put a solar panel.
so drivers side front is 56" x 32" rear is 72" x 44" pasenger side f...
Forum Discussion
you do realize when you have different size panels they all act like the smaller panel on the controler, right? I am trying to keep everything on one solar controler other wise I could go with two different size panels and get 1040 watts up there if I go with two controlers.
the issue is if you have say a 200 watt panels and a 300 watt panel on a single controler all you will get is 400 watts max. this was my original plan untill I did the research and found this out, I didn't realize this would happen either.
so for example I could put a 400 watt panel in the one side a 320 on the other, then two 200's up front. All I would get is 800 watts instead of 1120 watts. so if you put that zamp on the same controler you lost power not gained it. but it sounds like you have the two small panels on their own controler. another way to beat shading is to get panels with more busbars and diodes. that way if a panel is partialy shaded you don't lose it all in any situation. plus more busbars offer better performance in low light conditions. I kinda want to do the series/parallel set up as I like the higher voltage, it makes charging more efficient and it starts a couple hours, in the morning, before the 12V setup I have in the 5th wheel but thats not here nor their. If I lose one side it will be no big deal because I am almost trippling what I had in the old camper and I never said, "I don't have enough panels on this"🤣
My understanding is the voltage match is what matters. The panels will work like the lowest voltage panel. If you have 4 panels, 2x200 and 2x300, You would be best wiring them in series parallel, 200+300 and 200+300 to create a series match of voltage and other characteristics. My panels run through the one 150/70 MPPT controller. The panels I have are all within millivolts of each other and work well together. I've seen 840 watts from the array even though the array is rated about 780 watts. My experience is good with different sizes and one other brand in the mix but all producing near identical voltage. I was skeptical when I originally bought the panels but the dealer assured me they will work well together. He also informed me if I add another of the same battery, even though the existing batteries are 5 years old, a new of the same will work just fine with them. My batteries are at about 125 life cycles now and I think they are supposed to give me 1000 cycles and still be 80% efficient.
ya that is a thing also, you pick series or parallel to see which way will give you the most power then set them up that way, but either way they are still being limited by the smallest panel, its just weather by its amps or its cvoltage depending how its hooked up. I am just starting the deep dive into this and can't fully explain it right. I have two more night shifts then 4 days to get a good handle on it.
I think people used to do it a lot when panels were very expensive. they would find used panels and then use them. now panels are the cheepest thing you will buy for your rv pretty much. I can go out and get a 600 watt panel for 200 cdn right now and 450's for 175.00. if I could fit one of thoes on I would buy them in a heart beat. what has me pissed is I could get two 400 watt panels for about 375 and have 800 watts, have state of the art, high efficenty N type panels and on and on. now becaue I need smaller panels to fit the truck camper, I have pretty much decided to go with 800 watts still, but with four 195 watt byfacials that can give up to 33% more, but the way i will mount them I'll probably only see 200 or a bit more. this is going to be 700Cdn for the 4 panels, plus extra time and wire and mounting brackets. but by staying with one controler I'll save some to offset it. so this will give me 800 watts alsobut at 3 times the cost of two big panels. I can tell you when I do the 5th wheel it is going to get three or four 400-600 watt panels. I originaly was hoping that I could go with the new renogy shadowflux solar panels. They are very interesting but then the price is 300/195 watt panel which would take my cost up to 1200 bucks plus shipping. but I found out by using bifacials you increase your low light and shade preformance also, so I am leaning that ways now.
batteries even lifepo4 I wouldn't combine if they are more than a year of use on them. that is still debatable though it is just the way I look at it and several others. I gave away my original 280 ah battery I built because I wanted to build a new setup for the camper and the 5th wheel using the newer cells.
