Forum Discussion

Explorer

Aug 15, 2014

Solar Panel Spec - Can Someone Please 'Splain?

I was looking again at the specs on my new flexible solar panel:

21.7 Open Circuit Voltage
6.10A Short Circuit Current
19.9% Cells Efficiency
5.70A Optimum Operating Current
17.7V Optimum Operating Voltage

Could someone please explain what the 19.9% Cells Efficiency means?

Thanks!

14 Replies

pianotuna
Nomad III
Aug 15, 2014
Hi Mitch,

Yes, it is a good number.
xzyHollyxyz
Explorer
Aug 15, 2014
So, is 19.9% a good number?
pianotuna
Nomad III
Aug 15, 2014
Hi,

It means 19.9% of the light energy may, under ideal conditions, be converted to electricity. State of the art (which we can't afford) is about 27%. Older panels were often 13 to 14% efficient.

The number will drop over time with a 25 year working life for most panels.
12thgenusa
Explorer
Aug 15, 2014
It means a one square meter panel will produce 199 watts of power. The higher the efficiency the smaller the panel for the same power output.