Need help with DIY panels, only getting half power

I used low iron glass here is link https://www.environdec.com/Detail/?Epd=11718

[titosairbagsvc]

Need help, i have 9 panels Mono 300w Open-circuitVoltage(Voc) 40.10v and Short-circuitCurrent(Isc) 10.23A, and want to add a Poly panels of 315W Open-circuitVoltage(Voc) 46.2 and Short-circuitCurrent(Isc) 9.01A.

Can i use theme together in serial connection??, pls need som help, thanks a lot

[Mike90250]

Is your glass Low Iron glass, or simply stuff from the hardware store ? Low Iron glass is more transparent to the light than regular glass

[littleharbor]

Without linking the listing from eBay here's the title, Most listings of these sunpower cells listed boast this efficiency.

10 Pcs 3.34W C60 DIY Kit Flexible Solar Cell Sunpower Maxeon 21.8 High Efficiency.

Cell efficiency and finished panel efficiency are two completely different things.

[SunEagle]

Could you describe the method you used to calculate the 21.6 % efficiency ?

That is probably what the seller of those cells told him.

[J.P.M.]

Could you describe the method you used to calculate the 21.6 % efficiency ?

[jflorey2]

Hi,i am new here.i made diy solar panel 800w and solar cell efficiency is 21.6% and each panel out working volt 11 and 7.5Amp.here temperature is 40C.everyday generating 2.5unit to 3unit.i used 4mm glass and slygard 184 encapulation.max power output half.why i am getting half power.i used mppt 40amp and 24volt system.please help

Is your voltage or current lower than expected?

As a test, take an unencapsulated cell (hopefully you have one or two left) and use that as a reference. Compare your panel to that (multiply voltage by N cells of course) by measuring Isc and Voc. Then do the same behind a sheet of glass in case the glass is unexpectedly filtering part of the spectrum. Make sure the temperatures are similar when you compare the two.

Hi,i am new here.i made diy solar panel 800w and solar cell efficiency is 21.6% and each panel out working volt 11 and 7.5Amp.here temperature is 40C.everyday generating 2.5unit to 3unit.i used 4mm glass and slygard 184 encapulation.max power output half.why i am getting half power.i used mppt 40amp and 24volt system.please help