WAVE TECHNOLOGY & SOLAR PHOTOVOLTAIC CELLS

OBJECTIVES BY THE END OF THIS LESSON YOU SHOULD BE SAYING “I CAN…” LIST DIFFERENT TECHNOLOGIES THAT USE WAVELENGTHS AND FREQUENCIES TO CAPTURE AND TRANSMIT INFORMATION AND ENERGY EXPLAIN HOW SOLAR PHOTOVOLTAIC CELLS USE WAVELENGTHS AND FREQUENCIES TO CREATE ELECTRICITY I CAN EXPLAIN HOW THE WAVELENGTH AND FREQUENCY OF A WAVE ARE RELATED TO ONE ANOTHER BY THE SPEED OF TRAVEL OF THE WAVE. I CAN USE REFLECTION, REFRACTION, AND TRANSMISSION OF WAVES TO INFLUENCE THE ELECTRICAL POWER CREATED BY A SOLAR CELL.

RADIO

MICROWAVE

REMOTE CONTROL

VISIBLE LIGHT

UV LIGHT

PET/CT SCAN

TERRESTRIAL GAMMA-RAY FLASHES TERRESTRIAL GAMMA-RAY FLASHES (TGFS) ARE BRIEF BURSTS OF ENERGETIC GAMMA-RAYS PRODUCED IN THE ATMOSPHERE AND OBSERVED BY SATELLITES. THESE FLASHES OCCUR ON THE TOPS OF THUNDERSTORM CLOUDS. An artisits impression of a TGF. Credit: NASA. Hunstville USA

WHICH WAVE TOOK THE LEAST AMOUNT OF ENERGY FOR YOU TO CREATE? WHICH WAVE TOOK THE MOST AMOUNT OF ENERGY? CAN YOU RELATE THE SPEED OF TRAVEL OF THE JUMP ROPE TO THE NUMBER OF TIMES (OR FREQUENCY) THAT THE ROPE HIT THE FLOOR?

PHOTOVOLTAIC (PV) CELLS PV CELLS RESPOND TO VISIBLE LIGHT WAVELENGTHS. ALL OTHER WAVELENGTHS ARE EITHER TOO SHORT OR TOO LONG, GOING STRAIGHT THROUGH OR BOUNCING OFF THE SOLAR CELL. Roof-mounted PV solar array at Truckee Meadows Community College built by Black Rock Solar

Light from the sun has enough energy to knock an electron loose from an atom in a solar cell. These electrons move to the top of the solar cell and are conducted through metal strips to wires connected to the top of the solar cell to the back of the solar cell. The flow of electrons through this complete circuit creates electricity!

EXPERIMENT WITH DIFFERENT LIGHT SOURCES USE AT LEAST 6 DIFFERENT SOURCES ON THE SOLAR CELL AND OBSERVE RESULTS

SMALL GROUP DISCUSSION WHICH LIGHT SOURCES PRODUCED THE HIGHEST VOLTAGE? WHICH LIGHT SOURCES PRODUCED THE LEAST VOLTAGE? DID ANY PRODUCE NO POWER AT ALL? WHICH ONE(S)? DID YOU NOTICE ANY TRENDS WITH THE LIGHT SOURCES?

REFLECTION, REFRACTION, AND TRANSMISSION WORKING WITH MIRRORS, MAGNIFYING GLASSES & CHANGES IN DISTANCE

GATHER IN YOUR GROUP FIND A STATION THAT PRODUCED AT LEAST SOME VOLTAGE BE VERY CAREFUL WITH LIGHT SOURCES THAT CREATE A LOT OF HEAT! RECORD THE DISTANCE OF THE LIGHT SOURCE, RECORD THE VOLTS PRODUCED ON THE GRAPH USE THE MAGNIFYING GLASS TO SEE WHAT HAPPENS (IF ANYTHING!) USE THE MIRROR TO REFLECT LIGHT ON THE SOLAR CELL AND RECORD RESULTS. COMPLETE YOUR STUDENT GUIDES USING THE DATA YOU COLLECTED

RECAP CAN YOU DESCRIBE THE WAVELENGTHS AND FREQUENCIES THAT DIFFERENT TECHNOLOGIES USE, IN PARTICULAR THE SOLAR PHOTOVOLTAIC (PV) CELL. THE SHORTER THE WAVELENGTH THE ________________ THE FREQUENCY. THE LONGER THE WAVELENGTH THE _____________ THE FREQUENCY. WHICH HAS MORE ENERGY, SHORTER OR LONGER WAVELENGTHS? WHICH COLOR HAS MORE “ENERGY,” BLUE OR RED? WHAT COLOR DID THE PV CELL RESPOND BETTER TOO? CAN YOU USE REFLECTION, REFRACTION, AND TRANSMISSION OF WAVES TO INFLUENCE THE VOLTAGE CREATED BY A SOLAR CELL.