Author Topic: What do you think about this panel, estimated price?  (Read 1554 times)

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TheEquineFencer

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What do you think about this panel, estimated price?
« on: March 14, 2017, 04:07:37 AM »
I may be able to get panels like this at a reasonable price. I was wondering what reasonable is?

OperaHouse

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Re: What do you think about this panel, estimated price?
« Reply #1 on: March 14, 2017, 05:32:13 AM »
What do you think it is worth?  Where are you located.  Since you have MPPT it doesn't matter what voltage they are.  Generally grid tie panels are much cheaper.  I would never do 12V panels again.  I now have a local place where I can buy panels at about 70 cents a watt.

george65

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Re: What do you think about this panel, estimated price?
« Reply #2 on: March 14, 2017, 06:52:30 AM »

I have been doing a bit of horse trading in used solar panels.
I pay .20C/ w for panels 200W and over.  Under that I pay 10-15C/w.

These low watt panels are both relatively inefficent in output and effort. Normally these low output panels are not much smaller in size to the standard of 250W units.  The problem with that is several fold.
Firstly, you need a lot of roof space to add up to any worthwhile returns power wise.  Next, If you have the space, you need a lot of racking and fixings for all those panels. Add to that extra wiring, the fact the panels may well have older style Connectors that are hard to get/ match, more exy than current Mc4's and.... may not even be legal to install inless the connectors are upgraded to current standards.

You may have increased wiring runs for longer strings of lower output, much increased installation time if you are paying a licensed installer and so it goes.  Here many of the older panels are not even allowed to be reinstalled so you would want to check the standards in your area if you are concerned about having a compliant installation.

For me, where I am and with the availability of plenty of 225-260W panels. I'd be thinking twice about paying even $10 a panel.
Purchase cost is one thing, installation cost however also needs to be weighed into the equation to give a true $$ per Kw figure.

 I buy 250's for $50 to as little as 40 so based on that,  a 100W panel is near a non viable thing anyway and that's not even taking into account the different efficiency of the panels with regards to light levels, shadowing etc which are important in the over all ROI.

I spose if I could get a heap of the things I could put them on my fathers garage roof for him which is expansive but then I come back to the cost of racking and wiring to cover said roof when that cost could be reduced by at least 2.5X using 250W panels that would probably kick in sooner, out later and give more power on overcast days. 

I have noticed that the majority of people ask stupid prices for used panels. They almost always want to tell you what they paid for the things 3-7 years ago like they think that price is somehow relevant now.
They just took the 1.5 Kw system down to replace it with a 5Kw system that cost them $3-3500 all up but still think they should get a grand for the old panel and inverter that are not even legally compliant anymore.  When you point out the cost per watt of the new system is less than what they are asking for the old used panels alone and how they justify their price, 98/100 people will get all pissy and try to tell you they don't care about that, they still work so are worth what they want.

Just last sunday I replied to one ignorant clown who was going on about me trying to rip him off and told him I had an IBM 386 computer that had been upgraded with an extra 30Mb Hdd and a cd reader  that was worth over $7000 New before the upgrades and as it was still working perfectly with a clean copy of Windows 3.11, I would swap him this for his panels.
Must have driven the point home because I didn't get any more idiotic excuses to justify the value of his used panels after that.

I deal with people trying to tell me 15-20+yo cars with blown engines or transmissions that looked like they rolled down the side of a hill after dogs had been sleeping in them " Are still good cars" and ask laughable money for them  but I have never come across a level of  placing unrealistic vale on something as much as people do with used solar panels!

 I also often get that people have seen panels advertised for $xxx. I say yeah I have seen them advertised for that too.... month after month after month and they still have the ad going. What does that tell you?  Just because they ask a stupid figure does not make them worth that  or mean that's what they are being sold for.
Hard to talk logic to some people, they just have to work it out the hard, time consuming and ultimately expensive way.

In your question of "what's a reasonable price?"  I'd definitely be looking at the finished install sitting on the roof cost as well as the purchase cost of the panels which is only a portion of the all up cost and not as big a portion as you may expect.

TheEquineFencer

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Re: What do you think about this panel, estimated price?
« Reply #3 on: March 14, 2017, 09:18:04 AM »
george65, insight like yours, much like I say and do things, non-candy coated and politically dressed correctly is what I like. Right off hand, I can't remember what the max input voltage for a TRiStar MPPT is, but I think it's around 120-150V. These would be new panels, they use them on Solar light towers. I' open to suggestions as I am going to be shooting for 1000-2000W solar input into a battery bank. I want to pretty much go off grid here at my shop. The only loads at present I plan to leave on gridis a 7.5hp compressor, the Mig and Plasma cutter and maybe my 3ph mill and lathe if the VFD's do not like the inverter I end up buying.

I'm open to suggestions for panels. I'm in the states in Eastern,NC BTW.

If you know where I can get a crap load of panels, like the ones above I may have you a sale for them. I'll have to get with you sometime when time allows to discuss it at a later time. If there's a little "pocket change" to be made in it. I'm all for it.

Mary B

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Re: What do you think about this panel, estimated price?
« Reply #4 on: March 14, 2017, 03:08:52 PM »
Nothing wrong wth 12 volt panels if the price is right. Lighter, easier to handle, upgrading connectors is cheap if needed(depends on your local zoning laws in your country... you don't have a location listed so hard to help there), sure you need a little more racking but in the USA you can get unistrut for ~$18 at big box lumber yards http://www.menards.com/main/electrical/strut-support-systems/10-12-gauge-pre-galvanized-strut-channel/p-1444424000448-c-12477.htm?tid=7243352761436102750&bargainStoreId=3270.

You need to look at what is available locally, at what you can piece together yourself instead of buying over priced solar panel racking, and look at your local zoning laws for grid tie requirements. In my area to grid tie everything has to be UL approved. Off grid no issues using non-UL equipment if it isn't mounted on the house(my panels are 80 feet behind the house on a ground rack, if they burn no biggie!). Crimpers for MC4 connectors are readily available now on eBay as are connectors and pins if you need to upgrade things. Follow your local electrical code for everything inside and have it inspected if in the USA to make sure your insurance will cover it.

Warpspeed

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Re: What do you think about this panel, estimated price?
« Reply #5 on: March 15, 2017, 06:20:36 PM »
I think many people start out with this idea, by buying one panel, then later a couple more, and plan to gradually accumulate a very large number over time.

DO NOT DO THIS.

The problem  is that panels are all over the place with  efficiency, number of cells, voltage, and current ratings. The mounting hole positions will be different too.
You simply cannot hook up an odd selection of mixed panels together, either in series or parallel if they are all different.
Even if you buy them all from the same place brand new over time, they come from China in batches, and are often sourced from very different suppliers.

If you want 1Kw or 5Kw, save up your money and buy a matched set of panels, either new or second hand all in one go.

You can make a virtual tracker and have all brand X panels facing one way, and all brand Y panels facing another direction, and use two separate controllers. That works fine.  But you cannot mix the panels feeding one controller and expect it to work.

Have to agree with George, the smaller panels are usually rubbish.  Get a few or many 225 watts or higher if you possibly can.

SparWeb

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Re: What do you think about this panel, estimated price?
« Reply #6 on: March 15, 2017, 09:50:12 PM »
Last year I picked up two 80W solar panels at Costco, on clearance, for 80$ each (and that's Canadian dollars so more like 65 USD).  There were some inverters in the bundle, too.
In terms of a reasonable price for a new panel, start at 1US$ / 1Watt.  If those panels are used, out of box, or damaged slightly, you should pay a lot less than that.
Are you willing to pay 100$ for those brand-new 100W panels?  Wait, are they brand new or not?  What condition are they in?  This matters a lot.  You can get a big discount if even just the frame is scratched.
No one believes the theory except the one who developed it.  Everyone believes the experiment except the one who ran it.

System spec: 135w BP multicrystalline panels, regulated by Xantrex C40, DIY 8ft diameter wind turbine, regulated by Tri-Star TS60, 800AH x 24V AGM Battery, Xantrex SW4024

george65

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Re: What do you think about this panel, estimated price?
« Reply #7 on: March 16, 2017, 04:17:13 AM »

I got the current pricelist from a solar supply company a couple of days ago.
Was pretty surprised to see brand new Talesun 345W panels at .59C/W.  Trina's are .57c/W for 270's and .62C/w for 290's.

The days of $1 per watt are LONG gone. Thankfully.
Dunno how much cheaper they will get. They will level out and I think they are near that Plateau now.  One things for sure, your roof is going to be capable of supplying a LOT more power than it could just a few years ago.

Quote
The problem  is that panels are all over the place with  efficiency, number of cells, voltage, and current ratings.
You simply cannot hook up an odd selection of mixed panels together, either in series or parallel if they are all different.

You can hook up similar Voltage panels in strings but if you hook up dissimilar WATTAGES, each panel will only push the lowest wattage of the group.  IE, If you have say 10 panels in a string and 9 of them are 250s and 1 is a 100W, you wont get 2350W out of the string, You'll get 1000W. Maybe. It's like having an irrigation pipe of 2" with a piece of 1/2" somewhere along it. 1/2" flow is all you are going to get because that's the bottle neck.
Hooking up in parallel is a bit better but you'd still want similar voltages although the wattage wouldn't matter because they will work independent on that front.

Another thing I am of the opinion of rather than knowing for fact is with low wattage panels, the efficiency of the inverter may be worse for Higher voltage strings.  The afore mentioned example of 10 panels may only be 1Kw but if they are running at 360V or so, the inverter has to work harder to convert that to mains voltage.  I'm pretty surprised the heat my inverter generates with under a kw going through it and the string voltage being within 20-30v of the output. If you had double Voltage, I imagine the heat losses and inefficiency in conversion would be a lot more and exponential for the amount of power produced. I imagine with say 250W panels at the same Voltage, the conversion loss would be the same which would be a much smaller percentage of the actual amperage delivered.

Another thing I have found is the 3x 260W new panels I have on my "play" system generate a disturbingly close amount of power at the end of the day to my 1500W of 175w used panels. The difference in the daily output is more like 20% rather than the 50% as would be expected by the panel wattage differences. The irony is I'm getting good power totals for the used panels, the new ones just seem to over deliver on their rating.
The used panels were cheap and are repaying themselves well but as soon as I find some 250s again I'll replace them with those.

Johann

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Re: What do you think about this panel, estimated price?
« Reply #8 on: April 03, 2017, 06:28:00 PM »

I got the current pricelist from a solar supply company a couple of days ago.
Was pretty surprised to see brand new Talesun 345W panels at .59C/W.  Trina's are .57c/W for 270's and .62C/w for 290's.

The days of $1 per watt are LONG gone. Thankfully.
Dunno how much cheaper they will get. They will level out and I think they are near that Plateau now.  One things for sure, your roof is going to be capable of supplying a LOT more power than it could just a few years ago.

Quote
The problem  is that panels are all over the place with  efficiency, number of cells, voltage, and current ratings.
You simply cannot hook up an odd selection of mixed panels together, either in series or parallel if they are all different.

You can hook up similar Voltage panels in strings but if you hook up dissimilar WATTAGES, each panel will only push the lowest wattage of the group.  IE, If you have say 10 panels in a string and 9 of them are 250s and 1 is a 100W, you wont get 2350W out of the string, You'll get 1000W. Maybe. It's like having an irrigation pipe of 2" with a piece of 1/2" somewhere along it. 1/2" flow is all you are going to get because that's the bottle neck.
Hooking up in parallel is a bit better but you'd still want similar voltages although the wattage wouldn't matter because they will work independent on that front.

Another thing I am of the opinion of rather than knowing for fact is with low wattage panels, the efficiency of the inverter may be worse for Higher voltage strings.  The afore mentioned example of 10 panels may only be 1Kw but if they are running at 360V or so, the inverter has to work harder to convert that to mains voltage.  I'm pretty surprised the heat my inverter generates with under a kw going through it and the string voltage being within 20-30v of the output. If you had double Voltage, I imagine the heat losses and inefficiency in conversion would be a lot more and exponential for the amount of power produced. I imagine with say 250W panels at the same Voltage, the conversion loss would be the same which would be a much smaller percentage of the actual amperage delivered.

Another thing I have found is the 3x 260W new panels I have on my "play" system generate a disturbingly close amount of power at the end of the day to my 1500W of 175w used panels. The difference in the daily output is more like 20% rather than the 50% as would be expected by the panel wattage differences. The irony is I'm getting good power totals for the used panels, the new ones just seem to over deliver on their rating.
The used panels were cheap and are repaying themselves well but as soon as I find some 250s again I'll replace them with those.
I seen prices like that, but the problem is that it does not include shipping. And since those panels are big they charge you an arm and an leg for shipping them, unless you pick those panels up yourself.

glort

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Re: What do you think about this panel, estimated price?
« Reply #9 on: April 03, 2017, 07:10:18 PM »
if they were close that would be ok.