Lesson 5: Investigate the Impact of Solar Panel Angle on Energy Storage Efficiency
PREPARATION
ENGAGE
Spark curiosity about how panel angle affect solar energy storage.
Core Teaching Steps:
Show Images:
Display photos of solar panels at different angles, asking: "Why do solar panels have different angles? Could angle affect how much energy they store?"
Initial Predictions:
Present a hypothetical scenario:
"A solar panel tilted at 0° (flat) vs. 40° (steep). Which do you think will generate more voltage? Why?"
Record student guesses on the board (e.g., "steeper angles capture more sunlight" or "flat angles are better for direct sunlight").
EXPLORE
Investigate the relationship between panel angle and charge efficiency.
Core Teaching Steps:
Connection:
Angle Control:
Use an adjustable stand and protractor to set panel angles: 0° (flat), 40°, 90° (perpendicular to light source).
Code:
The basic formula for capacitors is: Q = C × V
In this experiment, the Capacitance Value used is 2.5 farads (F).
Therefore, the conversion formula from analog values to charge quantity (which can be understood as the stored energy of the storage module) is as follows:
Procedure:
1.Position the solar panel to a light source (e.g., sunlight) directly above the panel.
2.Set panel angle to 0°, wait 3 minutes for stable readings, record Charge Quantity both at the beginning(minimal value in 5 seconds) and the end(maximal value in 5 seconds).
3.Repeat for 40°, and 90°, repeat the step 2 at each angle.
Data Collection:
Charge Input = End Charge(mC) - Beginning Charge(mC)
EXPLAIN
Analyze data to explain the angle-charge efficiency relationship.
Core Teaching Steps:
Data Visualization:
Plot a line graph with panel angle (°) on the x-axis and charge quantity (mC) on the y-axis. Highlight the peak at 40° in the sample data below.
Ask: "Why did voltage peak at 40° instead of 0° or 90°?"
Scientific Explanation:
Key Principle:
The optimal angle maximizes the incidence of light being perpendicular to the panel surface. At 0°, light hits at a shallow angle (low efficiency); at 40°, the panel faces straight from the light source.
Analogy:
Compare to holding a paper plate to catch rain: tilting it at the right angle (not flat or upright) captures the most water.
CHALLENGE
Monitor the storage module status and display whether it capacity is sufficient on the screen..
Core Teaching Steps:
Connection:
Threshold Detection Setup:
In this experiment, the storage module has a rated voltage of 5.5 V. When fully charged, the voltage detection module outputs 5500 mV (5.5 V is the upper limit for safe use; exceeding this during charging may cause explosion or leakage). Therefore, a threshold is needed to remind users when the storage module has sufficient charge to turn on the LED strip. When the charge is below a certain threshold, users should be prompted to turn off the strip for recharging.
Program Logic:
When the charge is greater than or equal to 11000 mC, display “CHARGE READY” on the screen, else display “CHARGING”.
When the screen shows “CHARGE READY”, you can turn on the LED strip by switching the toggle below to ON. When the screen displays "CHARGING", switch the toggle to OFF to turn off the strip and wait for recharging. (If the LED strip cannot be lit even when the charge is sufficient, press the Boot key to activate the strip.)
Code：
Extended Activity:
Test the power consumption rate of the LED strip.
CONCLUSION
1.Key Takeaway: Reinforce the logic: "Optimal angle → higher light absorption → more energy stored → longer lighting."
2.Extension: "How could you design a circuit to auto-switch between daytime charging and nighttime lighting? (Hint: Use the light sensor loaded on Unihiker.)"
3.Cleanup: Guide students to disconnect devices, return materials, and tidy workstations.
Program-L5.zip 
