Source: PVEducation.org

Module Measurement Method for Solar Panels

Introduction

The module measurement method for solar panels involves using the variable of resistance to determine the power IV curve of a specific panel. This method allows users to compare and contrast factory-provided curves for their modules, helping identify the maximum power point and any deviations from manufacturer specifications.

Measuring with a Load

To operate a module at its maximum power point, the module voltage (V_MP) and current (I_MP) need to be determined. The load resistance (R_load) can be calculated using Ohm’s law: R_load = V_MP / I_MP. Most modules have labels indicating performance under standard test conditions (STC).

Materials Needed

– Two Multimeters (for voltage and current)
– Water for cooling resistors
– Alligator clip cords
– Protective gloves
– Resistors
– Solar Module

Measurement Procedure

1. Place the module in full sunlight.
2. Measure V_OC and I_SC.
3. Add resistors as per schematic and record voltage and current for each.
4. Change resistor values to cover the IV curve.
5. Remeasure V_OC and I_SC.
6. Swap resistors to gather results.

Results and Discussion

Recording voltage, current, power, and resistance for each resistor allows for the calculation of the power output and fill factor (FF). Comparing measured results to module specifications can reveal discrepancies due to variations in temperature and light intensity during measurements.

Conclusion

The module measurement method using resistance provides valuable insights into the performance of solar panels, helping users understand and optimize their energy output. By following a systematic approach and analyzing the generated power IV curve, users can make informed decisions regarding their solar energy systems.

Source: Arduino Forum