A Review of Solid State White Light Emitting Diode and Its Potentialsudfor Replacing Conventional Lighting Technologies in DevelopingudCountries

摘要

Lighting is an indispensable energy end use of man. A significant number people in developing countries liveudwithout electric lighting and depend on oil-based lamps. Globally, lighting consumes substantial amount ofudenergy and is a major contributor to green house emissions. Conventional electric lighting systems such asudincandescent lamps are highly inefficient and waste energy while the fluorescent/CFL lamps contain toxicudchemicals like mercury. Incandescent lamps with short lifespan as well as the fluorescent/CFL lamps poseudenvironmental waste disposal problems (e.g.). The use of renewable energy resource such as solar and windudpower systems for example as sources of power for the most efficient and long life lighting source such asudhigh-brightness light emitting diodes (LEDs) (also known as solid state lighting) would reduce global energyudconsumption for lighting by half, with corresponding reduction in green house emissions. In developingudcountries solar powered solid state lighting (SPSSL) would ensure access to electric lighting by the disperseudpopulation who may not be connected to the national grid in the near feature. In this article we elaboratelyudreview the upcoming solid state lighting technology. The physics and principles of operation of LEDs are alsoudreviewed. The impact of this new lighting technology on developing countries in the areas of commerce,udeducation, health and environmental impacts in comparison to conventional lighting technologies is the mainudthrust of this review.