Watts is depending on how your panel that you make is wired together.
Here's an example what a 2"x2" cell specs is
Amps per cell - 0.88 - 1.10
Volts per cell .57
The difference between the 2 is that the 2 cells wired in series produce a higher voltage but the amps it produces stays the same. The 2 cells wired in parallel will produce more amps but the voltage will stay the same. Now the part that makes things a little confusing is where you are at. No cells will produce exactly the same amount of volts and amps each. So wiring them in series and or parallel the wattage won't be exactly the same as 2 cells with. You could have a 2"x2" cell produce 0.50 volts at say 0.75 amps and a 2"x2" cell producing 0.57v at 1.10 amps.
I can't do the math for that kind of difference because 1 I don't know how it would go and 2 I don't want to give the wrong numbers on it.
So you could end up with a 2 cell panel that will produce a different amp and voltage thus the wattage will be different. How hot the cells get how much sun strength and many other things come into play on how much a panel will produce.
I don't understand.
P=VI
P = power, in watts (rate of energy flow) - this is equivalent to how much work can be done by flowing water
I = current, in amps (rate of charged particle flow) - this is equivalent to volumetric flow rate of water, ie gallons/s
V = voltage, in volts (electrical potential between 2 points) - this is equivalent to the potential energy of water, ie the height difference
2 cells wired in series will be like 2 pipes wired in series. amps remain the same (first one pipe has 10 gallons/sec flow through it, then below that the second pipe has 10 gallons/sec flow through it) but the voltage doubles (your height difference has doubled, you have 2 pipes on top of each other). Now when you collect that energy at the bottom of the pipes with a water wheel it has fallen 2 pipe heights instead of just 1 pipe height so it will hit the water wheel twice as hard, which results in twice as much power.
2 cells wired in parallel will be like 2 pipes wired in parallel, each with their own water wheel. each pipe still has 10 gallons/sec flowing through it, but now you have 2, so your total volumetric flowrate is really 20 gallons/sec. The voltage remains the same (only 1 pipe height). Now when you collect that energy at the bottom of the pipes you have twice as much volumetric flowrate hitting it (20 gallons/sec) but it is all falling only 1 pipe height, so it doesnt hit the water wheel(s) as hard.
I understand that real world differences such as different intensity of sunlight, duration of sunlight, etc will effect the measurements from one time period to another. However given a constant energy input I would expect a constant energy output equivalent to the area of the collection site regardless of how it is wired like cannabineer suggests. V and I may adjust, but P should remain constant.