LED Lights vs. Incandescent

Transcription

1 LED Lights vs. Incandescent Lights vs. CFLs Depanjan Sarkar

2 What is an LED? LEDs, or light emitting diodes, are semiconductor devices that produce visible light when an electrical current is passed through them. LEDs are a type of Solid State Lighting (SSL), as are organic light emitting diodes (OLEDs) and light emitting polymers (LEPs).

3 Inside a Light Emitting Diode 1. Transparent Plastic Case 2. Terminal Pins 3. Diode

4 LED: How It Works When current flows across a diode Negative electrons move one way and positive holes move the other way

5 LED: How It Works The wholes exist at a lower energy level than the free electrons Therefore when a free electrons falls it losses energy

6 LED: How It Works This energy is emitted in a form of a photon, which causes light The color of the light is determined by the fall of the electron and hence energy level of the photon

7 How is LED lighting different than other light sources, such as incandescent and CFL? LED lighting differs from incandescent and compact fluorescent lighting in several ways. When designed well, LED lighting can be more efficient, durable, versatile and longer lasting. LED lighting products use light emitting diodes to produce light very efficiently. An electrical current passed through semiconductor material illuminates the tiny light sources we call LEDs. The heat produced is absorbed into a heat sink.

8 Common LED colors include amber, red, green, and blue. There is actually no such thing as a white LED. To get white light the kind we use for lighting our homes and offices, different color LEDs are mixed or covered with a phosphor material that converts the color of the light. The phosphor is the yellow material you can see on some LED products. Colored LEDs are widely used as signal lights and indicator lights, like the power button on a computer.

9 Energy Efficiency and Costs

10 Life Span (Average ) LEDs 50,000 hours Incande scent Light Bulbs 1,200 hours Compact Fluoresce nts (CFLs) 8,000 hours

11 Watts of electricity used (equivalent to 60 watt bulb). LEDs Incande scent Light Bulbs Compact Fluoresc ents (CFLs) LEDs use less power (watts) per unit of light generated (lumens). LEDs help reduce greenhouse gas 6-8 watts 60 watts watts

12 Kilo-watts of Electricity used LEDs Incandes cent Light Bulbs Compa ct Fluores cents (CFLs) (30 Incandesc ent Bulbs per year equivalent ) 329 kw/yr kw/yr. 767 kw/yr.

13 Annual Operating Cost LEDs Incandes cent Light Bulbs Compa ct Fluores cents (CFLs) (30 Incandesc ent Bulbs per year equivalent ) Rs. 2181/ye ar Rs /ye ar Rs. 5091/ye ar

14 Environmental Impact

15 Contains the TOXIC Mercury LEDs Incandescent Light Bulbs No No Compact Fluorescents (CFLs) Yes - Mercury is very toxic to our health and the environment

16 Carbon Dioxide Emissions (30 bulbs per year) LEDs Incandescent Light Bulbs Compact Fluorescents (CFLs) Lower energy consumption decreases: CO 2 emissions, sulfur oxide, and high-level nuclear waste. 451 pounds/year 4500 pounds/year 1051 pounds/year

17 Important Facts

18 Sensitivit y to low temperat ures LEDs Incandesc ent Light Bulbs None Some Compact Fluorescents (CFLs) Yes - may not work under negative 10 degrees Fahrenheit or over 120 degrees Fahrenheit

19 Sensitive to humidity LEDs Incandes cent Light Bulbs Compact Fluorescents (CFLs) No Some Yes

20 Turns on instantl y LEDs Incand escent Light Bulbs Yes Yes Compact Fluoresce nts (CFLs) No - takes time to warm up

21 LEDs Incandes cent Light Bulbs Compact Fluorescen ts (CFLs) Durabil ity Very Durable - LEDs can handle jarring and bumping Not Very Durable - glass or filament can break easily Not Very Durable - glass can break easily

22 LEDs Incandesc ent Light Bulbs Compact Fluorescent s (CFLs) Failure Modes Not typical Some Yes - may catch on fire, smoke, or omit an odor