150 likes | 371 Views
Solar cells. Clean energy, natural resource. What voltage does your panel get from the indoor light (at lab-table height)? Raise the panel up to the fluorescent light. How high can you get the voltage? How high can you get the voltage using the overhead projector?
E N D
Solar cells Clean energy, natural resource
What voltage does your panel get from the indoor light (at lab-table height)? • Raise the panel up to the fluorescent light. How high can you get the voltage? • How high can you get the voltage using the overhead projector? • Can you determine which terminal is positive (left or right)? • Put your answers in the EXCEL document. Investigate . . .
Download the EXCEL document from the T-Drive. • What is the average voltage and standard deviation for each column? • Which method gives the highest voltage? • Turn in your spreadsheet, with averages and standard deviations, to the drop folder. Analyze
Partner with another group and try to wire up the panels to combine their voltages. If it works, show me. • Can you use the panels to power a small motor indoors? If it works, show me. • If it doesn’t work, try combining 3, 4, 5, etc. panels. Does that work indoors? Design . . .
Check the voltage of one D-cell battery. • Can one D-cell battery power the fan motor? Show me. Batteries vs. solar panels
In direct, outdoor sunlight, can one solar panel power a fan motor? If so, show me. • What is the maximum voltage of the solar panel in direct sunlight? • What happens if you combine panels and try to run the motor? Try it. Take it outside . . .
What did you learn? • What new questions arose? • Please get everything ready for the next class • Turn in your answer sheets. Wrap-up
Yesterday, we had an interesting and confusing issue with the solar panels and the fan motors. What was it? A grounding question . . .
Indoors, connect a capacitor to your solar panel and “charge it up”. Keep a voltmeter hooked up too, so you can see what’s going on. • Try to discharge the capacitor through the fan motor and see if the motor runs. • Try it through a light bulb too. • Let me know “yes” or “no”. • If you have the black capacitors, use 3 solar panels. Storing the energy . . .
Take the capacitors and solar panels outside and try again. What’s different this time? • Trade capacitors with another group and try again. • Try charging the capacitors outside and then bringing them inside to power the motors or the bulbs. Storing energy, continued.
Try connecting multiple solar panels to one capacitor. What does that do? • Try it indoors and outdoors. • Don’t connect more than 3 panels to one capacitor. Variations
Put a “resistor” or “resistors” in the circuit. This will slow down the rate at which the capacitor discharges. • See how long you can make the fan or light bulb run (even if it’s just barely running). • Let me know what your record is. A challenge . . .