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LEDs VS Energy-saving Light Bulbs. Term 2 Science ACE Done by: Hoon Tian Jun, Terrence. What are LEDs?. a.k.a. light emitting diode a semiconductor light source d emonstrates the phenomenon of electroluminescence . Practical Usage of LEDs.
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LEDsVS Energy-saving Light Bulbs Term 2 Science ACE Done by: HoonTian Jun, Terrence
What are LEDs? a.k.a. light emitting diode a semiconductor light source demonstrates the phenomenon of electroluminescence
Practical Usage of LEDs replacements for neon and incandescent indicator lamps seven-segment displays (in telephones, calculators, watches etc.) Illumination (advertising, automotive lighting etc.)
How do LEDs Work? LEDs are made up of semiconductors, materials with varying abilities of electrical conductivity consists of a section of N-type (cathode) material bonded to a section of P-type (anode) material with extra holes when electrical current is applied to the diode, electrons from the N-type side travel to the P-type side, falling into one of the holes the energy from the electron falling into a hole is released in the form of a photon, which is a particle of light, giving off light as a result
Pros & Cons of LEDs Pros Cons Efficient energy use Long lasting Radiate little heat in the form of infrared Quick on/off response Small sized High initial price Dependence on surrounding temperature
Energy-saving Light Bulbs? a.k.a compact fluorescent lamp (CFL) a fluorescent lamp designed to replace incandescent lamps
How do CFLs Work? CFLs contain argon and mercury vapor also have an ballast, which produces an electric current to pass through the vaporous mixture, colliding with the gas molecules when the gas gets excited, it produces ultraviolet light the ultraviolet light in turn stimulates a phosphor coating on the inside of the tube as this coating absorbs energy, it emits visible light
Pros & Cons of CFLs Pros Cons Low initial cost Versatile Energy efficient (compared to incandescent bulbs) Dependence on surrounding temperatures Sensitive to on/off cycling
Comparison • Compared to incandescent bulbs, both are superior • CFLs are the best choices for people who are not looking for anything more than illumination • LEDs are more cost efficient due to their longer lifetimes and durability, although the initial cost is higher Conclusion: LEDs are better than Energy saving Light Bulbs
References http://www.howstuffworks.com/led.htm http://en.wikipedia.org/wiki/Light-emitting_diode http://en.wikipedia.org/wiki/Energy_saving_light_bulb http://science.howstuffworks.com/environmental/green-tech/sustainable/cfl-bulb.htm http://www.planetbulb.com/pages/How-do-Compact-Fluorescent-Bulbs-Work%3F.html http://eartheasy.com/live_energyeff_lighting.htm