d esign for c onstraints neil e. cotter ece department university of utah [email protected]

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DESIGN FOR CONSTRAINTS

Neil E. Cotter

ECE DepartmentUNIVERSITY OF UTAH

[email protected]



decompressorare needed to see this picture.LED Lightbulb Constraints

• LED bulb design• Realistic design constraints

•Economic•Environmental•Social•Political•Ethical•Health•Safety•Manufacturability•Sustainability



decompressorare needed to see this picture.LED Bulb Design

• Individual LED’s• Metal heat fins• 110 VAC to 4 VDC power


are needed to see this picture.



[2][1]



decompressorare needed to see this picture.Economics

• Longterm Cost < CFL and Incandescent• Initial cost > CFL and Incandescent

[3]

Light

bulb projecte

d lifespan

50,000

hours

10,000

hours

1,200

hours

Watts

per bulb (equiv. 60

watts)

10 14 60KWh of

electricity

used

over 50,000

hours

300 500

700 3000

Cost of

electricity (@

0.10per

KWh)

$50 $70 $300

Bulbs

needed for 50k hours of use

1 5 42





decompressorare needed to see this picture.Environment

[4]

Light

bulb projecte

d lifespan

50,000

hours

10,000

hours

1,200

hours

Watts

per bulb (equiv. 60

watts)

10 14 60KWh of

electricity

used

over 50,000

hours

300 500

700 3000

Cost of

electricity (@

0.10per

KWh)

$50 $70 $300

Bulbs

needed for 50k hours of use

1 5 42

• Huge power savings depending on

hours of light use per day





decompressorare needed to see this picture.Society

• Can the poor afford LED bulbs?• Transition cost per room > $50

[5]





decompressorare needed to see this picture.Politics

• Incandescent ban postponed

[6]





decompressorare needed to see this picture.Ethics

• Should CFL and Incandescent be banned?

[7]







decompressorare needed to see this picture.Health

• Is quality of light adequate?• Can use phosphors to create colors

[8]

Light

bulb projecte

d lifespan

50,000

hours

10,000

hours

1,200

hours

Watts

per bulb (equiv. 60

watts)

10 14 60KWh of

electricity

used

over 50,000

hours

300 500

700 3000







decompressorare needed to see this picture.Safety

• Lower temperature?• Less heat• Lower voltage

Light

bulb projecte

d lifespan

50,000

hours

10,000

hours

1,200

hours

Watts

per bulb (equiv. 60

watts)

10 14 60KWh of

electricity

used

over 50,000

hours

300 500

700 3000





decompressorare needed to see this picture.Manufacturability

• Energy to manufacture < CFL and Incandescent

[9]





decompressorare needed to see this picture.Sustainability

• No mercury [10]

• Some arsenic and lead if manufactured poorly [11]

[11]





decompressorare needed to see this picture.LEDs are the Future

• Less energy

• Less toxic

• Less cost



[1]



decompressorare needed to see this picture.References

[1] http://eartheasy.com/live_energyeff_lighting.htm

[2] http://blog.makezine.com/2011/08/09/led-light-bulb-teardown/

[3] http://eartheasy.com/live_led_bulbs_comparison.html

[4] I.L. Azevedo, M.G. Morgan, F. Morgan, “The transition to solid-state lighting,” Proceedings of the IEEE, vol. 97 , issue 3, 2009 , pp.

481-510. Digital Object Identifier: 10.1109/JPROC.2009.2013058

[5] http://www.sears.com/shc/s/p_10153_12605_SPM6583418602P?sid=IDx20070921x00003a&ci_src=14110944&ci_sku=SPM6583418602

[6] http://www.washingtontimes.com/news/2011/dec/16/congress-overturns-incandescent-light-bulb-ban/

[7] Stevenson, R. “LEDs for less” IEEE Spectrum, vol 49, issue 1, 2012, pp. 39 - 40. Digital Object Identifier:

10.1109/MSPEC.2012.6117834

[8] I.L. Azevedo, M.G. Morgan, F. Morgan, “The transition to solid-state lighting,” Proceedings of the IEEE, vol. 97 , issue 3, 2009 , pp.

481-510. Digital Object Identifier: 10.1109/JPROC.2009.2013058

[9] S. Uddin, H. Shareef, A. Mohamed, M. A. Hannan, K. Mohamed, “LEDs as energy efficient lighting systems: A detail review,”

Research and Dev (SCOReD), 2011 IEEE Student Conference on, pp. 468-472, 2011.

[10] E.F. Schubert “Invited talk: Promises and challenges in light-emitting diodes for lighting applications”, Microelectronics and Electron

Devices (WMED), 2011 IEEE Workshop on, 2011, pp. 1. Digital Object Identifier: 10.1109/WMED.2011.5767269

[11] http://today.uci.edu/news/2011/02/nr_LED_110210.php

Neil E. [email protected]

http://eartheasy.com/live_energyeff_lighting.htm






http://blog.makezine.com/2011/08/09/led-light-bulb-teardown/



decompressorare needed to see this picture.

d esign for c onstraints neil e. cotter ece department university of utah [email protected]

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