LEDs vs. CFLs

There are lots of discussions of how LEDs are the ultimate power savers that beats all other methods of lighting. On the other hand, it only beats some lighting methods but not all. Compact fluorescent light (CFL), for instance, has similar efficiency in converting electricity into light to LEDs.

It’s funny that most people thought that vacuum tube technology was useless and CFL is just one of them that is still kicking! After reading some wiki I was reaffirmed that LEDs and CFLs actually have similar principles of operation, that is when you compare them with incandescent light. The two still have some slight differences if you care to know:

*While LEDs have conduction electrons moving inside semiconductor, CFLs have free electrons moving in glass vacuum tube.
*While conduction electrons excite semiconductor bonds in LEDs, free electrons excite gas molecules in CFL.
*While excited semiconductor bonds decay and directly emit light in LEDs, excited gas molecules emit UV light in CFL, which strikes fluorescent powder, which turns UV into visible light.
*There is electrical resistance in semiconductors against electron motion but no electrical resistance in vacuum tubes, but the fluorescent powder does waste energy converting UV into visible light.

I guess that’s why these trade-offs made them similar in efficiency. So what is your take on LED vs. CFL?

3 Responses to LEDs vs. CFLs

  1. Mild Lee Intereted says:

    Good question.
    CFLs contain mercury and this makes them a disposal/recycling challenge. The waste issues of semiconductor manufacture exist mostly at the manufacturing end, where they can (perhaps) be controlled. This is the reason given by, many “greenies” for promoting LED lighting over CFL – at least here in Australia.

    • liudr says:

      Most LEDs have Arsenic or Selenium, highly toxic. See the “Colors and materials” section on the wiki:


      I don’t know how much is used per lamp compared with mercury in a CFL lamp. It’s like solar panels, “good” considered by the end user but dirty, very dirty to manufacture. One thing that makes me think that LEDs are actually better is that they last longer.

  2. Gary Grise says:

    outside of the mercury versus semiconductor materials (which are mostly inert in the silicon) or life expectancy, I like leds as they are quick on. In Vermont USA where I live, CFLS are low mercury and therefore require a long warm up to reach full intensity and it gets much worse as they get colder. So outside I have already turned CFLs off before they become bright. However the led lights are instant on bright.

Leave a Reply