1. Experimenting with Solar-Electric Energy Dr. Sandra Cruz-Pol Professor Electrical and Computer Engineering July 2, 20 08 An NSF Engineering Research Center for Collaborative Adaptive Sensing of the Atmosphere

2. Solar to electricity conversion Prof. Agustin Irizarry, UPRM

4. We will use 2 types of electric connections

5. Series Connection V= I R Elements connect on ONE side only.

6. Parallel Connection Elements connect on BOTH legs. I = V / R

7. 100mA 1.a. Series connection + 1.5V _ + 1.5V _ + 1.5V _ 100mA + 4.5V _ P=VI P= 100mA*4.5V = 450mW

8. Three photovoltaic panels connected in series to feed a music box. + Series connection provides: 4.5V, 100mA + Music Box

9. Questions Does the circuit works with solar and/or artificial light? How does the sound varies with the intensity of light?

10. 100mA 1.b Series connection with only 2 panels: less voltage + 1.5V _ + 1.5V _ + 1.5V _ 100mA + 3.0V _ P=VI = power P= 100mA*3V = 300mW Ej. Cell-phone charger, small radios

11. 2.a Parallel connection 100mA + 1.5V _ 100mA + 1.5V _ 100mA + 1.5V _ 300mA + 1.5V _ P=VI P= 300mA*1.5V = 450 mW All positives are connected together. All negatives are connected together.

12. 2.b Parallel connection with only 2 panels : less current 100mA + 1.5V _ 100mA + 1.5V _ 100mA + 1.5V _ 200mA + 1.5V _ P=VI P= 200mA*1.5V = 300 mW

13. Three photovoltaic panels connected in parallel to power either an LED light bulb or a fan. + Parallel connection provides: 1.5V, 300mA or

14. Which connection to use? Connection determines voltage and current. Depends on the appliance to be connected, requirements. Careful: if current is too large, it could damage the appliance.

15. Myth: Why is the Ocean Blue? FALSE: The ocean is blue because the sky reflection on its surface. TRUE: Water is blue.  frequency spectra  But you need a huge amount of it to really see its color.  Look at a swimming pool as it gets deeper; even on cloudy days. http://ece.uprm.edu/~pol/OceanBlue.html

16. Who is Nikola Tesla? Nikola Tesla – greatest contributor to Electricity.  Invented ac motor,  perfected dc motor,  invented radio transmission, (wireless)  designed Niagara Falls generator,  distribution systems,  fluorescence lamps,  remote control, wireless,  logic circuits,  3-phasic and many others.

17. Where to find this material? http://ece.uprm.edu/~pol/maestros **REMEMBER to give proper credit