Will 2 separate solar panels, identical except different solar-efficiencies, produce same output?

Question

I can't figure this out to confirm, from definitions of solar-efficiency (examples there don't specify rated wattage):

Will two separate solar panels that are identical (including rated wattage), except differing only by solar-efficiency, produce the same power wattage output (in identical conditions, in a given equal time)?

Would the lower-efficiency panel produce less, or would it be identical because the manufacturer-rated wattage is identical to the other panel?

I can't figure out if efficiency is already taken into account before the manufacturer-rating of a panel's wattage, or if it should be taken into account when calculating real-world output. I know that real-world performance will never meet advertised (ideal-condition) wattage; but whatever the real-world performance is, I want to confirm if it will be identical (or not) between two identical panels that only differ by solar-efficiency.

In other words, which of the below is valid [maybe we should say, assuming "ideals", like Standard Test Condition 1 Kw/m^2 irradiance]?

The Answer is A

A) Real-world kW output = Wattage kW * Number of hours

B) Real-world kW output = Solar-efficiency * Wattage kW * Number of hours

Answer 1

No. They will not be exactly the same in how much power they produce, but you can expect them to be fairly close, within 2%-5% depending on temperature and intensity of light. There are simple tests you can perform to more accurately determine the output of each unit individually. Efficiency shouldn't even be part of this calculation even if it does have a small effect on changes in the output as they degrade over time. Efficiency is only taken into account when you are trying to determine how much area different panels require.

Additionally, both of your formulas are incorrect and will cause you much confusion if you try to use them. The Kilowatt hours should be Kilowatts times hours, and not the other way around as you have them.

Answer 2

Solar panels that have been manufactured differently can very well differ in the I-V curve.

You can find the I-V model from Wikipedia: https://en.wikipedia.org/wiki/Theory_of_solar_cells#Equivalent_circuit_of_a_solar_cell

Specifically, the reverse saturation current and diode ideality factor could differ.

So a different solar panel, even if of the same wattage and same number of cells in series, can have slightly different characteristics.

If you have an MPPT charge controller or inverter, then it is supposed to find the maximum power point. A 100 W panel, no matter what the efficiency is, should produce 100 W at the maximum power point given standard illumination conditions. A lower efficiency panel just has more surface area to do that.

However, this is only at standard illumination conditions and only with MPPT. If the illumination conditions differ from standard, such as during cloudy weather or solar panel not directly facing the sun, or sun near the horizon with lots of air mass inbetween sun and panels, there can be a percent or two difference in the output of two panels of the same power.

Also without MPPT with a PWM charge controller, you're at the mercy of what the power output is at the point of the I-V curve where your battery accepts charge. Then two nominally 100 W panels can have even greater differences in their output than a percent or two.

The efficiency has already been taken into account in the output. So a 100 W panel with 16% efficiency is a 100 W panel, not a 16 W panel, and a 100 W panel with 20% efficiency is a 100 W panel, not a 20 W panel. But different solar cells can have a percent or two difference in the output if the illumination conditions are non-standard.