Photovlotaic Modules

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Photovoltaic module output comparisons.

The objective in matching a PV power source to its load is to get the load at the "sweet spot" on the Maximum Power Point (MPP curve). The vertical squiggly line is where the most power is being made by the PV. Each colored line is a different light level. Multiplying the I value by the V value where the MPP curve crosses a colored line gives the maximum wattage at that light level. The graph is from Wikipedia.

The light source was a Philips MH175/RFL lamp (see light intensity chart and lamp description for details). Measurements are at two distances (intensities): 150cm (1250 ft-candle) and full sun equivalent at 48cm (10,240 ft-candle). Outputs are taken as open-circuit volage and as short circuit current. PV output is very sensitive to subtle changes in visible lighting condiitons. Measurements are as accurate as possible, but have an estimated tolerance of +/- 20%.

 

PV module ID

(see module descriptions for key)

Open Circuit Voltage @ 1250 ft-candle

Short Circuit Current @ 1250 ft-candle

Open Circuit Voltage @ 10,240 ft-candle

Short Circuit Current @ 10,240 ft-candle

1

1.6V

4.5mA

2.4V

45mA

2

1.8V

2.7mA

2.5V

30mA

3

1.4V

7.7mA

1.7V

70mA

4

4.7V

4.0mA

6.5V

50mA

5

4.0V

8.2mA

5.0V

500mA

6

1.9V

20.0mA

2.3V

200mA

7

3.0V

7.4mA

4.3V

45mA

8

1.0V

35mA

1.1V

500mA

9

7.3V

13mA

8.8V

70mA

10

22.2V

6.3mA

25.0V

27mA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PC modules used in testing -- Module Key

PV1

 A garden walk light. About $6 each.

 

PV2

A garden walk light. About $6 each.

 

 

PV3

A car cooling fan. The motor will only start turning in the equivalent of full sun. It's from sciplus.com. The motor leads were wired backwards at the factory, so an ineffective solar knick-knack was actually useless. Ahhh, surplus!

     

 

 PV4

 

 

PV5

From an educational kit from Radio Shack

 

 

 

PV6

Carded merchandise from sciplus.com

 

 

PV7

Random PV modules from sciplus.com

 

 

PV8

A toy experimenter's kit from sciplus.com

 

 

PV9

large PV from goldmine-elec.com

 

 

PV10

A car accessory from sciplus.com. It's doubtful that 120mA would do much for a car battery...

 

 

PV-reg

A regulated supply from sparkfun.