energy living green

LED Light Bulbs

I hope you all had a lovely long weekend. Between the Holiday and adjusting to the ever changing schedule that is medical residency, Tuesday’s post got away from me. I hope you didn’t miss my wrap up on light bulbs too much. 

LED Light BulbLED stands for Light Emitting Diode. LEDs are comprised of a semiconductor material and two leads. Basically what happens is that when the LED is connected to a circuit, a voltage is applied to the leads. This provides enough energy for electrons to jump across the band gap, and when they do, they release energy in the form of photons, or light. The color of light emitted by the LED is determined by the band gap in the semiconductor. If all this talk of semiconductors sounds vaguely familiar, it’s because it’s the same concept behind solar cells. Only in this case, the energy is coming from the wall rather than from the sun. LEDs are great as far as energy efficiency goes because they require a very small amount of electricity to produce light. They are also compact, robust, and have long lifetimes. LED light bulbs are made up of a collection of LEDs designed such that they emit a white, or slightly yellow light. Recently LED light bulbs have become increasingly available for home lighting, so let’s see how they compare to Incandescent and CFL light bulbs.

  • Light Quality: Mixed Reviews. Like CFLs I have frequently read reviews that LED light bulbs produce light that is too cold. We can probably all easily identify LED holiday lights because they have that tell-tale blue tinge to the light. I am happy to report that the LED light bulbs that I recently purchased produce a warm soft light, just like we expect are accustomed to seeing from incandescents. LED light bulbs will probably need to become more mainstream before they beat the cold blue light rap.
  • Price per bulb: Con. Standard LED light bulbs typically run $10 a bulb. If you buy them in a six-pack you can get them for more like $9, but there is definitely a bit of sticker shock that comes with spending over $50 on lightbulbs just for your home use. And if you want anything fancy, like a dim-able bulb, you’ll easily be paying double.
  • Availability: Pro. You may not be able to find LED light bulbs on the shelves of your local grocery store yet, but Target, Home Depot, and Amazon all carry them, and I imagine many other stores as well.
  • Style: Con. Similar to CFLs, LED light bulbs fit standard sockets, but the choice of bulb is limited. There are candelabra bulbs, but they don’t look the same as the incandescent equivalent.
  • Energy use: Pro. An LEDbulb that produces a comparable amount of lumens as a 60 watt filament bulb requires only 9 watts.
  • Lifetime: Pro. 25,000 hours! You read that right, a LED bulb will last more than 3 times as long as a CFL bulb. That translates into nearly 23 years of light at 3 hours a day. The LED light bulb that I recently put in our lamp will burn for longer than my youngest brother has been alive. That’s crazy town.

And bonus: LED light bulbs contain mostly recycle-able materials. Contact your local recycling provider to see if they can recycle your old bulbs. Although, you can probably wait 20 years  or so before you have to deal with that.

So the tally when comparing LEDs to CFLs and Incandescents is 3 pros, 2 cons, and 1 mixed review. Now let’s look at the long term cost.

10 year cost for burning filament bulbs in one lamp: (3 hours a day, $0.12/kwh cost of electricity, $9.00/bulb, 1 bulb) = $20.83.

And bonus: that same bulb will burn for another 13 years at that rate.

Pretty cheap when compared to the $96.84 it would cost to run the same light with a incandescent bulb, and it even beats out the $22.40 for the CFL. 

And more importantly, over that same 10 years you could save 550 kWh of electricity if you switch from an incandescent light bulb, or 55 kWh if you switch from a CFL.