Post on 28-Jan-2015
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Presentation by:Richard Young
Senior Engineer/Director of Education
Energy Efficient LEDs For Sustainable Solid-State Lighting
The 6th Annual The Following background slides are from the UC, CSU, CCC Sustainability Conference: June 24-27th, 2007
For Sustainable Solid-State Lighting
Steve DenBaars
Slides are included in this presentation courtesy of:
Steve DenBaarsSolid State Lighting and Display Center
Materials and ECE DepartmentsUniversity of California, Santa Barbara
What is a Blue LED?
L.E.D.= Light Emitting Diode
An LED produces light by combiningpositive and negative charges inside a
Gallium nitride (GaN) crystal.
Blue LED
The Advantage of LED LightingLong life – lifetimes can exceed 100,000 hours as compared to 1,000 hrs for tungsten bulbs.
Robustness – no moving parts no glass no filamentsRobustness – no moving parts, no glass, no filaments.
Size – typical package is only 5 mm in diameter.
Energy efficiency – up to 90% less energy used translates into smaller power supply.
Non-toxicity – no mercury.
Versatility – available in a variety of colors; can be pulsed.
Cool – less heat radiation than HID or incandescent
Luminous Efficacy of Various Light Sources
Current number for GaN white LED at UCSB
i 116 l /W b hi
x
is 116 lm/W ucsb chip143 lm/W partner chip
LED
2006
First white LEDs were only5lm/W at 20mA (1995)
Graph taken from www.lampteck.co.uk
White LightWhite Light White LightWhite LightWhite LightWhite Light
3 Methods of Generating White LEDs
Substrate
UV GaN LED
UV light
RGB Light
Substrate
Blue GaN LED
Blue Light
Green, Red phosphors
Blue GaN LED
Green GaN LED
Red GaAs LED
Multi-Chip, RGB-best efficiency-highest cost
UV + Phosphors-best CRI, color -uniformity-low cost-improved reliability
Blue + Phosphors-lowest cost-30 lm/W->90%market share
“The Promise” Energy Usage Comparison
50
60
LEDs Save 53Watts
10
20
30
40
5060W Bulb
CompactFluor.LED
Pow
er U
sed
(Wat
ts)
0Light Source
“Best” White LED and Compact Fluorescent vs. 60Watt Light Bulb Comparison
Technical considerations• Heat sinks are critical!• Power supplies are critical!Power supplies are critical!
– constant voltage and current• Expensive at the moment• Costs are dropping• Can be placed in unique locationsCan be placed in unique locations• Install for eventual relamping
– non-permanent location• Lots of innovative products!
Practical applications• Exit signs• auto/truck lights• stop lights
fl hli h• flashlights• signage - backlighting• spot lights, floodlights, basic “a” lamps • pendants, down-lights• linear, string and cove lighting • ambient textural theatrical ultraviolet• ambient, textural, theatrical, ultraviolet• parking lot, path lighting• task (desktop)• neon replacement• case lighting and under-counter lighting
Promising applications for food service
R16 flood light4.8 watt LED = 20 watt halogen
R30 flood light11 watt LED = 60 watt halogen
cool or warm white and CRI = 80$120
4.8 watt LED 20 watt halogencool or warm white and CRI = 80
$50
LED Decorative ($180)
LED fixture = 2 watts
mini - CFL fixture = 9 watts
incandescent fixture = 40 watts
www.everlumelighting.com
LED Downlight ($210)
source: www.everlumelighting.com
Neon replacement and SignageSpecialty applications
Decorative lighting
LED Cove Lighting Modules($150)
2 lamps = 1 watt each uniti t frequires transformer
fits into flexible track sockets
source: www.everlumelighting.com
source: www.lighting.philips.com
Basic retrofit application:LED lamps in existing EXIT signs.
The new standard: LED Exit signs
• $50/year savings• new sign cost $30new sign cost $30• no relamping = reduced maintenance costs• no burnouts = increased safety• less than 5 watts per sign.
LED Candle
Norex enterprises
Korean Store wrapped in LEDs
source: www.xilver.nl
Future SSL DisplaysPocket Projector/Cell Phone
Prototype from Novalux using frequency double lasers