LEDs, or light emitting diodes, are at their simplest an extremely efficient and long lasting form of solid state lighting. While incandescent bulbs rely on delicate filaments suspended in a gas, LEDs are simply small capsules, in which tiny chips are placed on a heat-conducting material. As SFGATE's Home Guides details, LEDs possess a compelling set of advantages when applied to sustainable, energy-efficient lighting.
To begin with, LEDs are small. Measuring between 3 to 8 mm in length, they can be employed individually or as part of a larger array that magnifies their effectiveness. Their small size allows for them to be used in applications where the size of an incandescent or CFL bulb would be prohibitive, and since LEDs project light in a single direction instead of radiating it, their energy efficiency is dramatically increased.
This efficiency is also bolstered by the low operating temperatures at which LEDs function. Traditional bulbs waste the majority of their energy output as heat, a byproduct of the light-generating reaction. In incandescent bulbs, fully 90 percent of the energy utilized is radiated as heat, while CFL bulbs are only slightly more efficient, demonstrating an 80 percent energy loss. LEDs, by comparison, invert this relationship, giving up just 20 percent of their energy as heat. According to EcoDirect, LED lightbulbs also operate using just 10 to 20 percent of the power a comparable incandescent bulb requires.
The length of life displayed by LEDs is also a major draw for consumers interested in the technology. High-power white LEDs are projected to last 35,000 to 50,000 hours, compared to just 750 to 2,000 hours for an incandescent, or 8,000 to 10,000 for compact fluorescents. This long life expectancy is a function of an LEDs lack of a filament, which makes the diode far more resilient. LEDs generally will simply fade in brightness as they age, rather than experiencing a catastrophic failure, an all too common memory for users of incandescent bulbs.
LED lights also demonstrate strengths and weaknesses when used with dimmer systems. Their low voltage consumption can cause dimmers to see them as extinguished, while they in fact are still radiating a small amount of light. Some LED bulbs are prone to buzzing and flickering when dimmed, though their susceptibility to these undesirable qualities is often a function of the manufacturing processes behind them. An impressive strength of LEDs (or an inherent weakness if you are accustomed to or prefer traditionally dimmed lighting) is their ability to maintain a consistent color spectrum as they fade. While an incandescent bulb will subtly shift from white to yellow as voltage is withdrawn, LEDs demonstrate a steady white light throughout their operating range.
A Newport Ventures consumer response survey articulates the many ways in which LED lights are uniquely positioned to meet the demands of homeowners and builders. Though the vast majority of people responded that they were only somewhat familiar with LED lighting, those surveyed clearly favored certain factors they considered important when choosing a lightbulb, as well as qualities that would drive them to invest more in the product.
Nearly 70 percent of those polled noted that they considered the energy savings inherent in a bulb, while just over 60 percent focused on cost. When asked what would make them pay more for a lightbulb, the overwhelming majority of survey respondents, over 70 percent, chose the life expectancy of the product as a driving factor. Energy Star certification was the next highest ranked factor, polling just under half of respondents. The vast majority of those surveyed also articulated their unwillingness to pay over $15 for a lightbulb, even one that is considered "high performance."
The results of the survey clearly demonstrate that LED lighting possesses strengths uniquely harmonious with consumer demands. Their long life expectancy, combined with dramatic energy efficiency and increasingly affordable retail price, mean that LED lights deliver in the areas where homeowners are most closely paying attention, making them an extremely attractive option.