Used solar panels

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Used solar panels

February 04, 2021, 05:05:44 am

In central, FL.. hope the experts can help

There are many options.. 180, 225, 250, 300, 425

Ranging from 50 to 150 each.

The story, solar companies in FL get tax breaks for replacing thes every 5 years.

Specs; monocrystiline 250 watt, 37.5 volt (my meter says 34-35v, 15A for the 8 I am looking at.

David is 70, bought 200, installs these for people in MI and just put 300 watt system at his house.. I saw it.

Questions;
1. Do solar panels wear out...note my Siemens 75w from 1995 still produce 90% of 17.5 rated
2. Mono VS polly not much difference?

Any other questions I should ask?

Thanks Folks for your help.

Re: Used solar panels

Reply #1 – February 04, 2021, 07:28:44 am

These are Trina, manufacture

Re: Used solar panels

Reply #2 – February 04, 2021, 09:48:43 am

Hi John,
My input to answer your questions:
Do Solar Panels wear out? Normal degradation is around .5% per year in the industry. This is normal, no problems... For Commercial Operations we modeled a 20 year lifespan, they of of course continue to function way past that date... Search NREL solar panel degradation for more details.

Mono vs. POLY? TYPICALLY Poly panels new, typically cost less. Poly tends to have slightly better dispersed light pickup, such as cloudy days. Mono panels generally have higher efficiency. Both are good.

Trina Solar is a Tier 1 Manufacturer, good stuff. I've installed thousands of them...

I'd find a local source for panels like you have, shipping on small quantities is very expensive.

Bring your voltmeter, check voltage on a sunny day if you can. Should be "in-range" of what it says on the back panel or spec sheet, that's about all you can do electrically to test without other equipment. Check for discoloration of the silver lans on the PV side of the panel, could be heating from mishandling or micro cracks, (if they really are used panels). Check the back sheet, should have no discoloration or issues.

Lots of left over solar panels everywhere, good way to pick up inexpensive solar!

Jeff

Re: Used solar panels

Reply #3 – February 04, 2021, 10:36:19 am

Our solar panels are from 2009 and seem to work just as well now as when new. Poly vs Mono? Check YouTube tests. Not really much difference.

Check reviews on controllers as you don't want one to fail when on a trip. A controller to handle 1200-1500 watts is going to cost about $600 . Ours has not skipped a beat in all these years. If the coach is outside with a tarp over the top, it still charges and will keep the batteries up.

Panels are super cheap now so figure $0.33/watt. Our four 285 watt potential panels would be 330 watts today at their size. Find the panel deals on Craigslist, that's how we found ours. A guy that was installing thousands in a solar farm had extras so a deal.

Lots of good panels from the U.S., Canada, China, Germany. Manufacturers of commercial panels can't build inferior panels or would go out of business. Ours are Yingli.

Pierce

Re: Used solar panels

Reply #4 – February 04, 2021, 07:10:10 pm

Sun Electronics, in the Miami, area is where I've bought B panels from Sun Electronics – World's Lowest Solar Panel Prices Customer service could be better, but some of the best prices I've found.

San Tan Solar, in the Phoenix area, usually has used, or B, Sun Power panels, as well as other brands, for sale at reasonable prices. SanTan Solar | Wholesale Solar Panels For DIY, RV and More! This is where I bought the used Sun Power 250W HE panels on out coach. San Tan has a good article on panel degradation, linked on the home page.

Both of the above sell BOS components. Another good place for BOS is RES Supply RES Supply: Renewable Energy Systems for Less. RES has a minimum purchase $300?

Greg

Re: Used solar panels

Reply #5 – February 04, 2021, 07:34:59 pm

In looking for about 30 seconds at the Sacramento CL, I see new German 325 watt, 19% efficient commercial mono cells in the shorter 64 inch size for $140. Florida has to have like deals.

So, $600 for 1300 watts plus $600 for a top controller plus wires, mounts, etc and for less than $1500, you have an excellent system. Add another panel or two if you have a residential fridge.

This is why it's hard to buy used panels.

https://sacramento.craigslist.org/grd/d/sacramento-325w-solar-panel-mono-qcell/7268887807.html

Pierce

Re: Used solar panels

Reply #6 – February 05, 2021, 05:19:34 am

Looks like a good buy, the 325 watt are 80

Re: Used solar panels

Reply #7 – February 05, 2021, 10:30:50 am

Quote from: fouroureye – February 05, 2021, 05:19:34 am

Looks like a good buy, the 325 watt are 80

But they are 1968 mm (77 inches) long and you have to buy a bunch. This means you are more limited in the number that will fit on the roof and the wattage per square meter will be less.

Solar Panels – Sun Electronics

Pierce

Re: Used solar panels

Reply #8 – February 05, 2021, 10:49:55 am

We are in Benson, AZ now and found some used Trina panels for a great price. Issue may be the sizes, as we have 3 airs on our coach of 40 foot. Would have to mount them on the sides of the rig along side the air conditioners and still would have some issues with getting around up there! Decisions, decisions. These panels are 250 watt panels as well. Looking at 6 for a total 1500 watts.

Re: Used solar panels

Reply #9 – February 05, 2021, 11:10:47 am

Quote from: juicesqueezer – February 05, 2021, 10:49:55 am

We are in Benson, AZ now and found some used Trina panels for a great price. Issue may be the sizes, as we have 3 airs on our coach of 40 foot. Would have to mount them on the sides of the rig along side the air conditioners and still would have some issues with getting around up there! Decisions, decisions. These panels are 250 watt panels as well. Looking at 6 for a total 1500 watts.

What is a great price and how long are the Trina panels? While the 325 watt panels I posted are $140, they are only 65 inches long so 1300 watts only takes 4 shorter panels. Most of the panels are 39 inches wide. I have to be careful walking also as there is not much distance between them as you can see in my old posts. I use a ladder as much as possible. Ours are 39"x72"

On the other hand, if you can squeeze 77 inch panels on your roof, that can be 375 watts for each panel. 1500 watts for only 4 panels.

Our 1140 watts is plenty for anything we do without ever having to start the generator. But we have an RV fridge.

The 65 inch panels are also lighter for installation but should still have three mounts down each side for security in high winds while driving.

Pierce

Re: Used solar panels

Reply #10 – February 05, 2021, 03:03:14 pm

If I were going to do my solar install over again I would approach it differently.
The panel cost is only a portion of the TOTAL cost of the install. Because of the total cost of the installation I would buy the most efficient panels CURRENTLY made along with the current state of the art controllers and batteries.
Its a package your installing, not a piece.

Re: Used solar panels

Reply #11 – February 05, 2021, 03:28:30 pm

Quote from: Lon and Cheryl – February 05, 2021, 03:03:14 pm

If I were going to do my solar install over again I would approach it differently.
The panel cost is only a portion of the TOTAL cost of the install. Because of the total cost of the installation I would buy the most efficient panels CURRENTLY made along with the current state of the art controllers and batteries.
Its a package your installing, not a piece.

Lon,

This is the time where many will be updating their systems and yes, good to look at the 20% plus efficient panels as they are a bargain today and can add watts to an existing small system.

Controllers have not seen any real improvement since we purchased our Midnite 150 a dozen years ago. It's still at the top of the heap: Best Solar Charge Controllers in 2021 [Reviews, Pricing & Specs] | Unbound Solar

Any system with the best components is only going to cost $1500 for 1300 to1500 watts for the whole thing not including batteries if you do it yourself. It's so easy that just about anyone can do it and save a bundle.

While batteries are part of the package, the type chosen is going to have the biggest difference on the price. No right or wrong here. It just depends on budget, type of use, etc.

While the whole thing is a package, it pays to research each piece for quality, availability and price. That way, you get the best system for the lowest price.

If you research it, you can do a better job than most solar RV shops and just as good a job as the very best solar companies

Pierce

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Used solar panels

February 04, 2021, 05:05:44 am

Re: Used solar panels

Reply #1 – February 04, 2021, 07:28:44 am

Re: Used solar panels

Reply #2 – February 04, 2021, 09:48:43 am

Re: Used solar panels

Reply #3 – February 04, 2021, 10:36:19 am

Re: Used solar panels

Reply #4 – February 04, 2021, 07:10:10 pm

Re: Used solar panels

Reply #5 – February 04, 2021, 07:34:59 pm

Re: Used solar panels

Reply #6 – February 05, 2021, 05:19:34 am

Re: Used solar panels

Reply #7 – February 05, 2021, 10:30:50 am

Re: Used solar panels

Reply #8 – February 05, 2021, 10:49:55 am

Re: Used solar panels

Reply #9 – February 05, 2021, 11:10:47 am

Re: Used solar panels

Reply #10 – February 05, 2021, 03:03:14 pm

Re: Used solar panels

Reply #11 – February 05, 2021, 03:28:30 pm

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