For some time, consumers have been excited about the energy savings and efficient production of light from LED (Light Emitting Diode) technology compared to traditional light sources (incandescent and fluorescent). Most lighting design professionals, however, still approach the general use of LED technology with a bit of trepidation since many LED products have come to market prematurely with various issues. The advantages and disadvantages of light sources are:
Incandescent
- A 19th century technology where a filament is heated to the point where it glow.
- Pluses: Produces a warm light most people find inviting; very inexpensive to produce.
- Minuses: Short life; low quality of light relative to the amount of energy used.
Fluorescent
- An early 20th century technology where electrodes excite a gas inside a tube causing a glow on phosphor coatings.
- Pluses: Relatively efficient light production; color quality has improved over the years.
- Minuses: Tubes are not conducive to focusing (versus incandescent spotlights); concerns about toxic contents; has probably reached the limits of improvement.
LED
A late 20th century technology with more of a relationship to the components of computers than more familiar lighting sources.
- Pluses: Long life; efficient production of light from energy used.
- Minuses: Heat dissipation; component integration and reliability; consistency of color rendition; lack of optical assemblies to create usable real world fixtures; high price.
The good news is that LED technology is finally beginning to overcome its drawbacks. At Lightfair International, the largest United States architectural lighting conference, LED technology has been the star of the show for the last few years. Advances in LED technology have, for the first time, made LEDs a viable option for architecture lighting of spaces in certain applications:
- Manufacturers are overcoming color temperature and color rendering issues of LEDs in a number of ways including: color mixing where red, green, blue, amber, and white LEDs are combined to create the desired color temperature; and improvements in remote phosphor technology where color is added to the light produced by the LEDs with a colored phosphor to help correct color shortcomings, essentially using some of the techniques of both incandescent and fluorescent lamps
- Pricing for LED products is still high, so users should carefully consider the complete Life Cycle costs versus other technologies.
- An increasing variety of fixtures are now available to meet aesthetic requirements.
The current challenge is that LED technology is arbitrarily being used as the source for just about every lighting condition imaginable, even though it is not necessarily the best solution after all parameters and needs are considered. The best light source is one where the entire light fixture assembly maximizes the qualities of the light source in order to meet the project needs. LED technology may or may not be the answer, but is becoming a viable option.