EBAY Solar Panel -- good deal ?

Started by Windpower, April 19, 2009, 12:14:09 PM

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MountainDon

The $2.60 price per watt is excellent. From what I hear Evergreen are good panels.

I noted they are not UL or CE listed so if there is going to be an inspection done according to NEC rules they will not pass.

I have seen the same blemished panels with UL/CE for $3.45 per watt. http://www.affordable-solar.com/Evergreen-ES-A-205-fa2b-205W-PV-BLEM.htm  also available in black finish.

Check the rates for shipping included and make a decision then.
Just because something has been done and has not failed, doesn't mean it is good design.


Windpower

Thanks for the input Don

I think I am going to go for it

I found a pallet of six for the same price per watt but only 210 for shipping (300 lbs)

this is exciting

there goes the tax refund
Often, our ignorance is not as great as our reluctance to act on what we know.

Windpower

just did it


1260 watts of solar panel coming my way

next is a charge controller

thinking of the Morningstar Tristar 60  (48 Volt) since it will handle a high input Voc voltage and up to a 4 kw array

has and RS232 input for computer control -- that might be handy at some pont

seems priced right at about $ 200  mol

anybody familiar with this brand ?



Often, our ignorance is not as great as our reluctance to act on what we know.

MountainDon

For a PWM controller it's fine. The Max Voc is high enough that even on the coldest winter morning it should be fine.


I do prefer MPPT types though for the greater efficiency in poor weather. However, they do cost more.


What's the panel wiring going to be; how many series/parallel?
Just because something has been done and has not failed, doesn't mean it is good design.


Pritch

Great deal on the panels!  Have you chosen your batteries yet? 

-- Pritch
"The problem with quotes from the internet is that they're not always accurate." -- Abraham Lincoln

Windpower

Can you recomend a MPPT contoller, Don ?


Probably 8  L16 Trojans, I can get them locally for a good price
Often, our ignorance is not as great as our reluctance to act on what we know.

MountainDon

Quote from: Windpower on April 20, 2009, 07:15:05 AM
Can you recomend a MPPT contoller, Don ?

Outback FLEXmax 60 or 80. Completely programmable, battery system voltages of 12 up to 60,  VOC of 150, 60 amp and 80 amp models.

http://outbackpower.com/products/charge_controllers/flexmax/
Usually best price is from TheSolar.biz  Give them a phone call, their website doesn't always have the exact current price. You have to talk to them to order anyway; no online ordering. Friendly, knowledgeable folks too. I've bought from them.

Outback has a nifty array sizing tool
http://outbackpower.com/resources/string_sizing_tool/

Just because something has been done and has not failed, doesn't mean it is good design.

Windpower

Thanks Don


I think from the specs I'll wire 3 in series then parrallel into two banks

Imp is 18.4 V (I think) times 3 = 55.2 volts about right for a 48 volt bank I think

I'll check the outback models


Often, our ignorance is not as great as our reluctance to act on what we know.


MountainDon

#9
The Vmp = 18.4 volts per panel, which would produce 55.2 volts with three in series.

For the absorption and bulk stages of charging I use a value of 2.35 volts per cell. Using that, a 12 V system requires 14.1 volts, a 24 V system requires 24.2 volts, and a 48 V system requires 56.4 volts. At first glance those three panels in series appear to be marginal or undesized for a 48 volt bank of batteries.


I double checked that using Outbacks string sizing tool.  Those Evergreen panels are not in Outbacks database so I entered the numbers myself from the Evergreen panel specs; Voc: 22.8 Volts, Vmp: 18.4 Volts, Isc: 12.10 Amps, Imp: 11.15 Amps. I used a value of 0.1 for the Vtoc and Vtmp which is typical ( I couldn't find the exact numbers, but those factors hardly make any difference.

Using the ambient air temperature corrections of a high of 90 degrees F and a low of -25 degrees F the Outback sizer comes up with a max Vmp of 56 volts for three in series. They call that unusable for charging a 48 volt system. Their calculator says 4 or 5 panels in series would be okay with either of their controllers.


My Outback FLEXmax charger manual states the suggested voltage set point for absorption charge is 59.2 volts for 48 volt batteries. Float is suggested to be 55.2.

There is a charging voltage chart at The Solar.biz The chart is at the bottom of the page.

I think you need two more panels, one for each series set. 

:( :(
Just because something has been done and has not failed, doesn't mean it is good design.

Windpower

I talked to the guy yesterday


he says he has hundreds more

2 more won't break the bank

A friend is interested in a couple -- I may just order another 6 if these look good

I am not too concerned about being able to equalize them from the panels -- probably do that from a generator

one source recomended an equalizing charge every six months -- shouldn't be too big a problem to crank up the diesel genny for a couple hours every 6 months


Often, our ignorance is not as great as our reluctance to act on what we know.

Windpower

I just received the panels

they look exellent

I can hardly wait to get them up and running

now I need to order the controller
Often, our ignorance is not as great as our reluctance to act on what we know.

pagan

You can put each one in the sun and hook up a voltmeter and see what they're each producing. I'd be interested to know as these are advertised as "blemished."

MountainDon

Can you see visible blemishes?  The blemished panels I've seen had physical production defects mainly on the frames. They were supposed to produce the full factory rated electrical output.

A no load voltage reading will not provide much information; in bright sun it should go to Voc.
Just because something has been done and has not failed, doesn't mean it is good design.


Windpower

We had to off load each one from the pallet to get them in the van

a superficial look over and they looked perfect -- them blems must be small

we have some sun today so I think a little test is in order

if they all check out I am going to order another 6 (while they last)

Often, our ignorance is not as great as our reluctance to act on what we know.

Windpower

They all look like this




This is a close up of the cells -- some have a 'mottled' color to them and some are not

this is the only problem I can see



I wish I had an ameter that went that high but I did hook on to a 12 V battery and I could hear the acid bubbling -- raised the voltage on the battery from 12.8 to 13. 6 in about a minute (it's only a 7 A Hr batt)
Often, our ignorance is not as great as our reluctance to act on what we know.

pagan

Wow, they look perfect from the picture. Maybe Don's right and the blemish is only with the framing. For a little over a grand I can almost double my array output.

Windpower

I have one under test now

car ammeter (not too accurate probably)  looks like about 11 A  mol


I hooked it to deep cycle batt from the camper

starting voltage of batt 12.3 V

I'll give it an hour and recheck it

I did find a couple surface scatches on the frames

but I had to look pretty close

The shipping is where it gets you (unless you live in Miami FL)

$210 for 6 panel

$160 per single panel plus $40 foreach additional one

BTW there is less than a day let on the eBay auction (but I think he has more from when I talked to him)


single panels here

http://cgi.ebay.com/205-Watt-Solar-Panel-2-60-per-watt_W0QQitemZ220384953359QQcmdZViewItemQQptZLH_DefaultDomain_0?
hash=item220384953359&_trksid=p3286.c0.m14&_trkparms=72%3A1205%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1309%7C301%3A1%7C293%3A1%7C294%3A50




six panel pallets here

http://cgi.ebay.com/Pallet-of-SIX-205-Watt-Solar-Panels-2-60-Per-Watt_W0QQitemZ220384952703QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item220384952703&_trksid=p3286.c0.m14&_trkparms=72%3A1205%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1308%7C301%3A1%7C293%3A1%7C294%3A50



Often, our ignorance is not as great as our reluctance to act on what we know.

Windpower

Well that was fun


I loaded the panels into the other van --- all 350 pounds of them

was a tight fit cause I couldn't move the 440 pound metal lathe very far (another Craig's list bargain -- almost new with lots of extras for $650 )

making a run up to the farm tomorrow -- supposed to be in the 80's

hope it makes those morels start popping, last year it was too dry -- got only a few

and the  turkeys gobblin

now where did I put those turkey loads.... 


later, I need a shower








Often, our ignorance is not as great as our reluctance to act on what we know.

Windpower

I just received my second order of 6 panels

they look excellent as well

Don,

I just called the Solar Biz and had a very long talk with Patty about charge controllers

Thank you for the recomendation

I really learned a lot and their prices are excellent too

of course now I am in 'analysis paralysis' until I get all this sorted out  ;D




Often, our ignorance is not as great as our reluctance to act on what we know.


MountainDon

You are welcome. They are good people.  :D
Just because something has been done and has not failed, doesn't mean it is good design.