Presentation by: Richard YoungSenior Engineer/Director of Education
The 6th Annual The Following background slides are from theUC, CSU, CCC Sustainability Conference: June 24-27th, 2007 Energy Efficient LEDs For Sustainable Solid-State Lighting Slides are included in this presentation courtesy of: Steve DenBaars Solid State Lighting and Display Center Materials and ECE Departments University of California, Santa Barbara What is a Blue LED? L.E.D.= Light Emitting Diode Blue LED An LED produces light by combining positive and negative charges inside a Gallium nitride (GaN) crystal.
The Advantage of LED LightingLong life – lifetimes can exceed 100,000 hours as compared to 1,000 hrsfor tungsten bulbs.Robustness – no moving parts no glass no filaments parts, glass, filaments.Size – typical package is only 5 mm in diameter.Energy efficiency – up to 90% less energy usedtranslates 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 is i 116 lm/W ucsb chip l /W b hi 143 lm/W partner chip x LED First white LEDs were only 5lm/W at 20mA (1995) 2006 Graph taken from www.lampteck.co.uk
3 Methods of Generating White LEDs White Light White Light White Light RGB Light Green, Red phosphors Blue GaN LED UV light Blue Light UV GaN LED Blue GaN LED Green GaN LED Substrate Substrate UV + Phosphors Blue + Phosphors Red GaAs LED -best CRI, color -lowest cost -uniformity -30 lm/WMulti-Chip, RGB -low cost ->90%market share-best efficiency -improved reliability-highest cost
“The Promise” Energy Usage Comparison LEDs Save 53Watts 60 50 Power Used (Watts) 60W Bulb 40 30 Compact Fluor. 20 LED 10 0 Light Source“Best” White LED and Compact Fluorescent vs. 60Watt Light Bulb Comparison Technical considerations • Heat sinks are critical! • Power supplies are critical! – constant voltage and current • Expensive at the moment • Costs are dropping • Can 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 • flashlights fl hli h • signage - backlighting • spot lights, floodlights, basic “a” lamps • pendants, down-lights • linear, string and cove lighting • ambient, textural theatrical 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 light 4.8 watt LED = 20 watt halogen cool or warm white and CRI = 80 R30 flood light $50 11 watt LED = 60 watt halogencool or warm white and CRI = 80 $120
LED Decorative ($180)LED fixture = 2 watts incandescent fixture = 40 watts mini - CFL fixture = 9 wattswww.everlumelighting.com LED Downlight ($210) source: www.everlumelighting.com
Neon replacement and Signage Specialty applications Decorative lighting
LED Cove Lighting Modules ($150) 2 lamps = 1 watt each unit requires transformer i t f fits into flexible track sockets source: www.everlumelighting.com
The new standard: LED Exit signs • $50/year savings • new 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 Displays Pocket Projector/Cell Phone Prototype from Novalux using frequency double lasers