measuring solar panel wattage

[reynier1223]

good day esteemed members of edaboard
I recently succeeded to build my own solar panel
a small prototype that generates about 16V DC
I am in need of a device or circuit diagram or a method that I can use to measure the amperage that the solar panel can deliver
Please any one that can help me I will appreciate it very much
Hope for response soon
Thank you in advance

 

[barry]

There is no device that can measure how much your panel CAN deliver (unless you short the output). That's like saying "how much current can the outlet in my wall deliver?". You can,however, measure how much it IS delivering at any instant; that would be an ammeter.

 

[beeflobill]

It sounds like you want to measure the I-V curve of your solar panel.

The solar panel will operate at a point on it's I-V curve depending on the load it is attached to. To get an idea of what a solar panel I-V curve basically looks like you can see **broken link removed**.

The basic idea is to measure the current and voltage for various loads. So, you set a load so to "force" a current and then you measure the voltage. Then you repeat for a range and currents and produce a graph. (alternativly, you can force the voltage and measure the currents).

There is equipment that can do this. But, for a cheap and laborious way to do it ... you can use a poteniometer with a voltmeter and an ammeter. Hook the pot up as a load to the solar panel. Measure the voltage across the pot with one meter and measure the current through the pot with another meter. Tune the pot to a range of voltages and plot the corresponding currents (or vice versa). Then you can have a pretty good idea of what your solar panel can do.

 

[Audioguru]

Obviously, the solar panel must always point directly at the sun so it must move. Clouds or window glass must not be in the way.
In the morning and late afternoon when the sun is low in the sky (unless it is on the equator in a desert) the power will be low. At night .....