PV Gap

Deanna Said:

Electrical circuit.............helppppppppppppppppp…

We Answered:

(a) Ohms law answers this.

i = V/R = 0.36 / 10 = 0.036 A or 36 ma

(b) Well, here the power is 0.36 v * 0.036 A = 0.01296 W or about 13 mW

If you have the exact I-V curve you can draw contours of constant power on it (i*v=constant) for various values of the constant and find the one that just touches the I-V curve. this will be the operating point that gives the most power.

You could also try to model the solar cell as a Thevenin equivalent

The Thevenin resistance would be 0.44 V / 0.04 A = 11 ohms.

the max power would occur with an 11 ohm load, so the power in the load would be half of the total power generated (the other half would be dissipated in equivalent resistance of the cell).

v^2 / R = (1/2)* (0.44)^2 / 22 = 17.6 mW

Clifton Said:

How to plot three sets of data in one graph - Excel?

We Answered:

You did not state which version of MS-Excel you are using, so I will assume it to be 2003 or earlier (though the same basic information is valid for 2007).

This should not be a problem. Just create three columns (B thru D) for your three X-axis "Cell Management" categories, using row 1 for the labels (Single, Serial, and Parallel). For column A, these cells could be used for various labels of the Voltage values, or nothing at all (not really required).

Then enter your Voltage values in the cells within columns B thru D starting from row 2 downwards.

Now select at least your three main columns (optionally column A). Use the Chart Wizard to step yourself through all of the options you may wish to choose during the 4-step process. Or just click FINISH initially when the wizard comes up to take all of the defaults.

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Marshall Said:

Will this finally change the minds of the Global warming zealots?

We Answered:

No because their methodology in the study automatically eliminates any impact of the trend rate in the data series on the resultant correlation.
http://tamino.wordpress.com/2009/07/24/o…

In other words, contrary to their claims, it's impossible for them to have determined the impact from ENSO on the global temperature trend. Apparently Carter didn't understand the methodology employed in his own paper.

More importantly, ENSO *can't* impact long-term temperature trends. It's not physically possible. The 'O' in ENSO is oscillation. It switches between positive and negative states, and the cool phases cancel out the warm ones. ENSO can't create or retain heat, it can only move it around between oceans and air.

So not only do the methods of the paper make it impossible to attribute a warming trend to ENSO, but ENSO physically can't cause a warming trend. Their comments have no basis in reality.

Theresa Said:

What is the measurement of one solar cell?

We Answered:

the maximum Power output at 1standard sun