Solar panel comparison

[-TX-]

I've had the darndest time seeking out the best PV for my application. Seems as if after each time I've found the right one I find something else. Specifically, I need 10 panels that are no wider than 32" but can be as long as 68", but I have found no online database that can be searched by panel dimensions.

I want the highest wattage I can fit, and that brings me to this comparison:

165 watts, mono:
Peak Power (Pmax): 165 W
Voltage at Peak Power (Vmp): 18.10 V
Current at Peak Powre (Imp): 9.12 A
Short Circuit Current (Isc): 9.58 A
Open Circuit Voltage (Voc): 22.81 V
Efficiency:18-19%

190 watts, mono:
Peak Power (Pmax): 190 W
Voltage at Peak Power (Vmp): 37.2 V
Current at Peak Powre (Imp): 5.24 A
Short Circuit Current (Isc): 5.88 A
Open Circuit Voltage (Voc): 44.6 V
Efficiency:15.3%

At first I was like awesome, Found another 250 watts!. Then, digging deeper, I realized the new find's poor efficiency and amperage. Does this matter though? 250 more watts is, after all, 250 more watts, and it doesn't matter if the PV is high voltage, low amperage, or low voltage, higher amperage as long as I size my strings properly. Is that correct?

[littleharbor]

You're comparing apples to oranges. One is a 12 volt panel, the other is a 24 volt panel. The 24 volt panel isn't less efficient necessarily, It is just running at higher voltage. Watts is watts.12 volt panels are usually 36-6"cells configured as 4 rows of 9 cells and in the 21 x 54" size range while 24 volt 5" cell modules are configured as 6 rows of 12 cells and are roughly 32 x 64".
Most 72 cell (24 volt) panels with 5" cells, will fit your size requirements. These particular panels are likely out of production now in favor of 6" cell panels. They were in the 150 to 190 watt range. I think you can still get Topoint 190 watt panels.

[SunEagle]

I would look at it this way.

The earlier panel designs were of lower wattage and in most cases low efficiency. Most were 36 cell with Vmp ratings at ~ 18vdc and were physically small frames.

They then started to get bigger and went to 60 cell (Vmp ~ 36vdc) with higher wattage and efficiency ratings and bigger frames.

Then they went to 72 cell with higher wattage ratings but maybe not better efficiency depending on the manufacture.

It still comes down to what you want to spend and how much you want to get out of the panel but now the inverter plays a part of how much you generate in the end where the panel use to play a major part in the beginning.

[-TX-]

You're comparing apples to oranges. One is a 12 volt panel, the other is a 24 volt panel. The 24 volt panel isn't less efficient necessarily, It is just running at higher voltage. Watts is watts.12 volt panels are usually 36-6"cells configured as 4 rows of 9 cells and in the 21 x 54" size range while 24 volt 5" cell modules are configured as 6 rows of 12 cells and are roughly 32 x 64".
Most 72 cell (24 volt) panels with 5" cells, will fit your size requirements. These particular panels are likely out of production now in favor of 6" cell panels. They were in the 150 to 190 watt range. I think you can still get Topoint 190 watt panels.

Thank you, Littleharbor, that's what I thought. BTW, they are Topoints. Would you recommend?

Cost is actually a bit less for Topoints, SunEagle. Not that it matters much. I can only do this once, and want to make it right.

[littleharbor]

Thank you, Littleharbor, that's what I thought. BTW, they are Topoints. Would you recommend?

Cost is actually a bit less for Topoints, SunEagle. Not that it matters much. I can only do this once, and want to make it right.

I don't know anything about them other than they are monocrystalline cells, are UL listed with the standard 10-25 year warranty and are made in China, as are a majority of panels these days. I wouldn't hesitate to try them if I had the need.

Before the 60 cell modules got so popular as grid tie panels 72 cell modules were the norm. Circa 2002-2007 or so.

[-TX-]

I'd rather American made but again, searching for size (or even panel composition) is extremely difficult. I've tried everything but only get results coincidentally.

[J.P.M.]

I'd rather American made but again, searching for size (or even panel composition) is extremely difficult. I've tried everything but only get results coincidentally.

Hard to find. Like it or not, American labor costs and automation have cost lots of American jobs. Additionally, most folks anywhere, including Americans, don't see the need to pay for, or any particular quality advantage in, buying American made stuff, which in addition may be no more than American assembled. For better or worse, market forces prevail, with labor, such as it may be needed in less measure due to automation, now being a fungible quantity. Get used to it.

[littleharbor]

Try Fred480V on Ebay. He has American made 160 watt 12 volt panels. Hi might have others. The 5" 72 cell panels are pretty rare these days though.

[SunEagle]

Thank you, Littleharbor, that's what I thought. BTW, they are Topoints. Would you recommend?

Cost is actually a bit less for Topoints, SunEagle. Not that it matters much. I can only do this once, and want to make it right.

I understand. I would focus on the inverter quality and remember that the older the panel the harder it will be to replace with an exact duplicate should one fail in the future.

The older panel technology usually is not manufactured for very long even if it was good.

[sensij]

At this bottom of the NREL library page (https://sam.nrel.gov/libraries) there is a CSV file of modules included in SAM. It doesn't list length and width explicitly, but does have area, which can be sued with some filters to narrow down your search. For example, the Sunpower E19, E20, X20, and X21 series has 245-255 W panels that are 31.4" wide, and looks like the highest power I think you'll find at that width. I think they are still being sold, but I don't know how easily you'd be able to pry just the panels from a Sunpower dealer.

The 72 cell version of the Panasonic (Sanyo) HIT panels are also >200 W, but harder to find since it looks like they've moved to a 96 cell standard.

Silveo's R series of their Triex panel were over 200 W, but they got bought out by SolarCity in 2014 and probably won't be found anymore.

It looks like JA Solar's JAM5 series can be also found, here is a 195 W panel:

http://www.ecodirect.com/JA-Solar-JA...-72-195-si.htm

All of these are more expensive than the Topoint's you are looking at.

[-TX-]

That's some insane level of research you did in my behalf, Sensi. Thank you. I'll take a look now.

edit: Not seeing the surface areas. Where do you see that and in which file?

[sensij]

At the very bottom of the SAM libraries page I linked, look for "California Energy Commission (CEC) Modules". Within that file, Column E, A_C, cec_area, is the panel area in sq m. Column F is the number of cells. Column U is the PTC. I used those columns to filter for panels that looked like they would meet your criteria. There are a few other sources of panel data online, but I haven't found any that list the dimensions either. Based on what I'm seeing, I think the Topoints are about as good as you are going to get for the money.

[-TX-]

Any idea what its restriction is that Topoint, for example, is not listed?

Edit: This is awesome!!

Edit: Very, very cool, but it appears as if I have found the best option in Topoint. They are still made and at $104 and change. All the 200w+ panels I searched for in the database either didn't exist anymore or were $300+

[Sunking]

I'd rather American made but again, searching for size (or even panel composition) is extremely difficult. I've tried everything but only get results coincidentally.

Good luck with that. Americans cannot compete. We have the Employment Prevention Agency, high taxes, and Activist like Dan to make sure things are not made in the USA and put workers out of work.

[-TX-]

Maga