Check your local Craigslist. People are selling brand new panels out of their garage, half the price of a store. I’m guessing they were surplus from those rooftop solar companies. But DO NOT BUY USED PANELS. They are not worth it as all panels degrade over time. You don’t want them unless they are free, and even then the owners probably just want someone to take their junk off their hands.
Several years ago I built a small off grid system just to see if I could do. Still works great, except lead acid batteries were the only way to go back then. I picked up some HUGE rooftop panels for a few hundred dollars, all brand new. I had to buy a roof rack for my BMW to carry them home, and they were almost as long and wide as my car. Should have seen the looks I got at stoplights. “Mommy, is that a solar powered BMW?”
Bring a voltmeter with you if you find one of these sellers. Google how to check them, to see if the voltage matches the placard on the back of the panels. Learn how to safely check them, as the large panels will shock you if you’re not careful. You, of course, half to measure them in sunlight, but you might want to throw a blanket over them to make the volt/current connections, THEN remove the blanket.
You should add to confirm that the panel cables end in MC4 connectors as all Bluetti stations use this type. Else buy kits with pairs of male and female MC4 connector pins and bodies, and a good crimping tool.
@Raymondjram Agreed. I purchased a bulk box from BougeRV and it has come in handy ALOT! Also I have found that some panels’ MC4 connectors vary from brand to brand, and my “disconnect” tool doesnt always work with them? Strange, I know… So by putting the bougerv ones on all them, I dont have to worry about the disconnect tool not working to get them apart.
All the regular glass panels I’ve seen come with MC4. Only the folding panels seem to have oddball connectors.
I wouldn’t waste my money on those folding panels when the rigid glass is much cheaper and more efficient. Of course, I don’t plan on going mobile with the ac500.
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I am disappointed how panel prices have increased. I paid $.50 a watt for mine 4 years ago. Now they are over $1/watt. You would think competition would have driven prices down over the years. I’ve got 2-600 watt arrays in the back yard, and I can rotate them to catch the morning sun, then swing them westwards in the afternoon. I forget what extra % power you can get from this, as rated by some gov’t agency, but I’m ready for a major blackout.
My 400 W panels are from a South Korean manufacturer, and I get them cheaper through a fellow engineer and contractor who has a local supplier. They cost me $280 or about $0.70 a watt. Today during very bright sunlight each panel produced 450 watts, and with four panels per AC300, this is about 1.8 kW. I plan to add more in parallel so I can get the maximum of 2.4 kW.
I know you have the AC300, but I noticed that on the AC500, even though it’s rated at 3000 watts PV input, the “catch” is that it’s actually 1500 watts per each PV input (DC1 and DC2). I don’t know the max wattage/input for yours, but it would be easy enough to split the wattage in half. Of course, in the real world we’re lucky if we get the rated wattage.
I’ve been shopping for more panels, but now that I’ve got the AC500 wired in and running, the one B300s just isn’t enough after the sun goes down. It was down to 12% at 2AM, so it would shut down before sunrise unless I plugged in the AC cord to charge it up to around 40%. We’re in a valley so it gets dark in winter around 4:30 pm, and the panels showed there wasn’t enough sun until almost 6:30 am. I’m waiting on my Bluetti Bucks to use on a 2nd battery.
I wouldn’t be too worried about used panels. Most will be fine. I have 1 kW of 10 year old panels and they are going fine. Tested them all with a Voltmeter
I have had solar on my roof for 23 years now and no more than 10% loss in output.
Well again, bring a voltmeter to check them, even for “new” panels. But hey, it’s your money.
Old used panels are likely polycrystalline. New panels are monocrystalline and push out a bit more power in hot climates, like Vegas, where I live. They also have better low light and cloudy capabilities.
@Jazzy The eb3a has a 12-28VDC, 8.5a, 200w limit on the solar input. So that means any panel that has a voc under 28v will work with the eb3a. The eb3a maxes out at 8.5amps and 200w so I actually run 2 of bougerv’s 180w 5bb panels in parallel with a “y-adapter” or parallel adapter. You can score these pretty cheap nowadays and they are pretty solid panels!
@ m.briney
Did your panels arrive from Bouge undamaged? Mine were poorly packed and suffered gouges and dents, enough so to put me off buying from them again.
@Joules22 Yea I have heard that from a couple different people but in my case, I had no issues both times I have purchased panels from them. I ordered 2 of the 180w 5bb panels back in August of 2020, and then ordered 2 of the 200w 9bb panels in November of 2021. Delivered promtly and no damage during transport. I will note that I had noticed when I purchased the 200w panels, they had stepped up their packaging and included these thicker black foam corner pieces for the panels. I still use these foam pieces actually for when I’ve needed to transport or store the panels.
I noticed Renogy started selling/shipping 2 panels at a time. Makes for a thicker box, but of course you can’t really prevent anyone from stepping on them during delivery, even though it says, “No step”
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On a side note, I emailed Amazon how with almost every single delivery, the boxes had torn edges, as if someone was trying to see inside, while every delivery from UPS or Fedex arrived in pristine condition. I guess someone there actually read my email because all their delivery boxes started arriving intact, with barely a scuff mark. With all the people they hire, it’s not hard to imagine someone WAS checking boxes for valuables, maybe to notify a partner porch pirate.
@St8kout Well im glad you’ve been having better luck with your deliveries! I myself have noticed a definite improvement on delivered parcels in the past few months, which is awesome because it was pretty rough during the height of the pandemic. Never really knew what was going to actually get delivered, and getting an item “on-time” was pretty much non-existent for us.