Old light - New light
True to form as an American, my family is a hodge-podge of ancestry new and old, New Englanders that were Mayflower descendants, mid-western farmers who were horse thieves or ministers, to immigrants here for just a few generations scraping by working in mills. I don’t think they ever made it to America, or if they did the left, but somewhere on my wife’s side of the family tree are Vikings. I imagine they were probably good at plundering, lighting their way with a good oil soaked torch. It’s good to know where you come from.
In the lighting family tree, the baby of the bunch is the LED light attempting to unseat the CFL as the next best thing. I’ve mentioned some innovations with LED’s recently, Mike’s talked about Cree lighting and we know it’s important to conserve with lighting as well. But If I had to ask any of those family members from long ago if they would rather spend $1 or say $30 on a light bulb (accounting for inflation and converting it to the currency that makes sense, say Viking Pennigars) I can guess the response.
Over generations things change, for one thing, humans now tend to live past thirty. Light bulbs last a lot longer too, especially LED’s. That sure is a bonus when the fixture is way up there, and requires a ladder, maybe a really long ladder! As I think about the benefits of LED lighting, I thought it would be good to find out where it came from and how it works compared to other types of bulbs.
LED stands for Light Emitting Diode, a diode being a thing that electric current flows through. Electrons flow, photons are emitted i.e. light. They are small and efficient but expensive.
Most are familiar with Compact Fluorescent Lighting, a CFL has a phosphorus coating on the tube that lights up when the argon and mercury vapors inside get charged with electricity.
The old fashioned incandescent bulb is essentially a heating element surrounded by gas which produces light. In fact an incandescent bulb 90% of its energy is emitted as heat rather than light, not very efficient for lighting but great for heating except that for most electric heating is not very cost effective.
GE invented the first practical LED in 1962 those of a certain age will recognize them as the vibrant red of clock radios watches and pocket calculators (these things now come in smart phones almost exclusively, but that little flashing green light telling you there is a message is also a LED) They’ve gotten better since then.
So what’s good about a LED lightbulb? Longevity: some last 35,000 – 50,000 hours better than a CFL’s 7,000-10,000 hours or an incandescent’s 1000 hours or so. Very inexpensive runtimes, a draw of 10w or so, a variety of color, blending different colors manufacturers can get a light that pleases the eye. Unlike CFL’s it’s not recommended that you evacuate the room when they break, and LED’s are dimmable. Next week I will talk about a few LED’s on the market now as well as some coming out by the end of the year that promise to be even better. Much better than whale oil lamps and torches, that’s for sure. My apologies to any relatives still using those, but there is a better way.
image of Match and LED’s from Wikicommons