JY Tsao ∙ Ultra-Efficient Solid-State Lighting ∙ IEEE LEOS Newport Beach ∙ Nov 2008 Ultra-Efficient Solid-State Lighting: Performance Frontier, Progress, Challenges Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy’s National Security Administration under Contract DE-AC04-94AL Jeff Tsao Physical, Chemical and Nano Sciences Center Sandia National Laboratories Cost of Energy ($/MW e h) Luminous Efficacy (lm/W e ) CN 1993 WRLD-NONGRID 1999 WRLD-GRID 2005 UK 1800 UK 1850 UK 1750 UK 1700 UK 1900 UK 1950 UK 2000 AU+NZ 2005 FSU 2000 OECD-EU 2005 JP+KR 2005 CN 2005 CN 2006 US 2001 After “The World’s Appetite for Light” (Tsao and Waide, submitted to the Energy Journal) Candles Gas Kerosene HID Fluorescent Incandescent SSL

JY Tsao ∙ Ultra-Efficient Solid-State Lighting ∙ IEEE LEOS Newport Beach ∙ Nov 2008 SSL Performance Frontier Wavelength (nm) Human Eye Response (lm/W) Color Rendering Index (R a ) Relative Power Relative Reflectances Munsell Samples 1-8 Luminous Efficacy (lm/W) CRI lm/W Color Rendering Index (R a ) 463 nm 530 nm 614 nm 573 nm CCT 3,000K, after “Ultra-Efficient SSL” (J.M. Phillips, et al, Laser & Photonics Reviews, 2007) 1/8 2/8 3/8 2/8 All linewidths 1-nm FWHM 100 nm 200 nm

JY Tsao ∙ Ultra-Efficient Solid-State Lighting ∙ IEEE LEOS Newport Beach ∙ Nov lm/W 2217 SSL Progress Report: Luminous Efficacy RG B B 60% eff R B G B B 60% eff R B G B B 15% eff SSL data from Luxeon K2 warm white lamps (Philips Lumileds 2008) RYGB 60% eff nm 4x 1.6x1.3x 14x SSL performances calculated using white LED simulator 5-3 (Ohno, NIST) Incand FluorHID B LEDR LEDGY LEDs Power Spectra Perf Frontier 614 nm

JY Tsao ∙ Ultra-Efficient Solid-State Lighting ∙ IEEE LEOS Newport Beach ∙ Nov 2008 SSL Progress Report: Ownership Cost of Light Operating Cost ($/Mlmh) Capital Cost ($/Mlmh) Incandescent Fluorescent HID SSL :6 Ratio Traditional lighting data from survey of 2001 U.S. market (Navigant) SSL data from Luxeon K2 warm white lamps (Philips Lumileds 2008) Cost of light calculated following “Light Emitting Diodes (LEDs) for General Illumination” (J.Y. Tsao, Ed., OIDA, 2002) 60% eff RG B B 60% eff R B G B B 60% eff RYGB Costs: Ownership = Operating + Capital Electricity Luminous Efficacy Power Delivery Cost Lifetime

JY Tsao ∙ Ultra-Efficient Solid-State Lighting ∙ IEEE LEOS Newport Beach ∙ Nov 2008 Key Points Lighting technology evolution in perspective –Over 3 centuries, 2.8 orders of magnitude improvement in luminous efficacy –SSL has potential to add final 0.6 orders of magnitude Performance frontier of SSL –408 lm/W at CRI 90 and CCT 3,000K –1/8 Blue 463 nm, 2/8 Green 530 nm, 2/8 Yellow 573 nm, 3/8 Red 614 nm –Narrower lines better, particularly in the red SSL Minor Challenge: Power Delivery Cost –4x from has reduced capital/operating cost ratio to 1/3 –2.2x from higher drive currents and lower manufacturing costs will easily bring capital/operating cost ratio to 1/6, same as traditional lighting SSL Major Challenge: Luminous Efficacy –1.8x from has been only modest improvement –4x from maintaining high efficiency at high flux in blue LED droop will beat traditional lighting –1.6x more from 60% efficient red LED at 614 nm –1.3x more from 60% efficient green and yellow LEDs at 530 and 573 nm