- Laboratory Exercise 2 Effect Of Shading On Solar Angle Of Incidence And Variation In Irradiation On Cells No Load Volta 1 (174.67 KiB) Viewed 55 times
- Laboratory Exercise 2 Effect Of Shading On Solar Angle Of Incidence And Variation In Irradiation On Cells No Load Volta 2 (129.31 KiB) Viewed 55 times
LABORATORY EXERCISE 2 EFFECT OF SHADING ON SOLAR, ANGLE OF INCIDENCE AND VARIATION IN IRRADIATION ON CELLS No load voltage and open circuit current of shaded solar cell Crystalline silicon solar cells consist of two layers of semiconductors with a positive and a negative charge. If light energy hits the cell, some photons are absorbed by the semiconductor. As a consequence, electrons are released from the negative layer and flow from the semiconductor to the positive layer via an external circuit. Without any load, a voltage can be measured at the outer contacts, which is the no load voltage. If the outer contacts are connected directly to a conductor, the maximum current will flow, the short circuit current. Objective: To determine how far the no load voltage and the short circuit current depends on the irradiated solar cell surface. Setup: 7 Postbc Southwar intensity controle Om Love! 1 Shading plates Soiar cult Figure 3 Procedure: 1. Set up the experiment according to figure 3. Ensure the multimeter is set to "DCV 2.0V", 2. Set controller to position 10. 3. Cover solar cell completely with 1/1 shading plate and record no load voltage. 4. Repeat with ½ cover, cover and without cover, and measure corresponding voltage. 5. Disconnect connecting cables, reset multimeter to "DCA 2000 mA" and repeat experiment to determine open circuit current. 6. Plot graphs of circuit and voltage against relative exposed surface 7. Again, without any shading record the open circuit current for solar cell and record in table... 8. Turn the position of the housing until position "0" by steps of 15 degrees and register the corresponding values. 9. Repeat steps 7-8 but record the no load voltage. 10. Plot a graph of short circuit current and no-load voltage against incident angle. Irradiated surface 0 [fully shaded] 1/1 [no shading] of solar cell No Load Voltage 0.158V 0.516 V 0.534 V0.540V [mV] Short circuit 0.19ma 93.5mA current [mA] 12 Short circuit current [mA] % volts 6.3mA 129.7mA ma Angle.(") 90 75 60 45 30 15 No Load Voltage 0.542 0.540 0.537 0.532 0.520 0.4880.338 Volts [mV] 129.7 128.6 126.6 122.2 103.5 48.1 2.09 mA 0
Observation and Discussion: Provide explanations 1. What can be concluded from measurement of no load voltage? 2. What can be concluded from measurement of short circuit Current? 3. What relations, if any exist between angle of incidence and short circuit current / no load voltage? 4. If different level of irradiation was used what would be the effect, if any, on the short circuit current and no load voltage? Sketch a graph to aid your explanation