Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Hot answers tagged

22

Mythbusters featured lightbulbs on Episode 69. The conclusions they came to were There is no appreciable lifespan impact from turning them off and on There is no cost savings from leaving them on to "warm up" Edit, FTFA: Bulb Longevity They tested one final element of this myth: frequently turning lights on and off decreases their life span, thus ...


22

There are a number of questions there. "Can LED light provide same amount of energy as sunlight?" In total, no, at least with humanity's available resources. The sun is kinda big. Per unit area? Sure, if you use enough LEDs and focus them tightly enough. "Can humanity get rid of the sun" Probably not, within our currently available technology ;-) ...


17

TLDR; don't use them for lighting. Given that you could keep your incandescent bulbs for when your current energy-efficient (I will assume CCFL) bulbs need replacing, your choice boils down to: buy a new CCFL; or use an incandescent that has already been manufactured. This helpful analysis gives the embodied energy in a CCFL as 1.7 kWh. Let's assume that ...


16

Perhaps this article is what you are looking for? It's a study by the US Department of Energy on the life-cycle environmental and resource costs in the manufacturing, transport, use, and disposal of light-emitting diode (LED) lighting products in relation to comparable traditional lighting technologies. There is a similar study done by manufacturer ...


15

Well, what causes the room to be dark? The light gets absorbed into objects and stays there. To keep the light buzzing through your room to make it feel bright, you need to make sure that as much in your room as possible reflects light. Mirrors reflect almost 100% of the light, i.e. more mirrors means less light absorption means a brighter room. Light ...


13

If you can't buy a specific bub that fits and you don't mind a slightly strange appearance then almost any mains powered dimmable LED bulb that fits and has the correct wattage (that narrow the field :-) ). could have a modifed base added by a competent technician or engineer. Be careful re "dimmable" - some LED bulbs are, some aren't. Some can use standard ...


12

Both incandescent and fluorescent are quite old technologies, and have been bettered in terms of efficiency and lifecycle impact. Furthermore, compact fluorescents aren't the only type of fluorescents. So although the compact fluorescents are superior to incandescents anywhere with a high-carbon marginal electricity supply (so almost all the world, in 2013, ...


12

The most common automatic light switch is a PIR sensor. I've looked up technical parameters of several such sensors. The idle (sensing) power consumption of most of them is 0.1 W. Some of them have the idle power consumption of up to 0.3 W and I believe some older ones could consume even 1 W. The active power consumption of the sensor is higher, but it's ...


11

I use them in garden/indoor. Something like this... (source : google search)


11

If it's your own building, you might be able to add on some sort of light tunnel outside the window or through the ceiling that extends to the roof to collect natural sunlight and beams it into your room: http://en.wikipedia.org/wiki/Light_tube Though if that were an option, a skylight might be an easier option. Lacking that, how about a mirror (...


11

i signed up just so i could make this comment. THelper♦ provided a good link to a DOE report on this topic, which i was researching because my roommate is skeptical about the advantages of efficient bulbs. the report THelper♦ cited has the following bar graph that pretty much answers the question:


11

Consumer tests have shown that there are good and bad LED lights; indeed some of them do not reach their advertized life span. I also have some bad experiences with LEDs dying long before their advertised end-of life, but that's anecdotes, not evidence. You can imagine that actually testing these is hard, it takes a long time! A major Dutch consumer ...


9

I think this is a great example of how sustainability really is multi-faceted. LED lighting may be great from an energy consumption standpoint, and not as good with respect to finite material usage. Energy Use vs Material Supply I think it's important, however, to apply some weighting to the different factors. I don't believe we're yet at a critical ...


8

The answer you are looking for would be contained in a Life Cycle Assessment (LCA). For an LCA you first want to determine the boundaries that are important to your question. Are you considering cradle to grave (disposal)? Cradle to cradle (recycling after use)? What are the boundaries for recycled source materials if used to make the light bulbs? The ...


8

I assume you are talking here about incandescent light bulbs. From looking around the Internet and from my personal experience, here is what I can say: In the countries I have lived in (France and Australia), I have always read that incandescent light bulbs should be thrown in the general waste bins. These kinds of specific recycling streams really depend ...


8

I disagree with the answers that say not to use it. It may in fact be an excellent idea to use it if: you live somewhere that requires your home to be heated in the winter you currently heat with electricity or with something less efficient than electricity The "wasted" energy from an incandescent bulb is wasted as heat. In the summer, this is really bad ...


8

To answer your question about whether or not it's financially worthwhile to swap them out, I looked at two simlarly rated lamps from the same manufacturer: Philips 60W equivalent CFL: 14W power consumption, 800 Lumens, CRI 82 Philips 60W equivalent LED: 11W power consumption, 830 lumens, CRI 80 So there's a 3W difference in power consumption between the ...


8

Sort of. Consider the pay back time. high efficiency lights are expensive. Expense is, at least in part, a measure of the resources used to make it. Replacing the fixtures in the kitchen where the lights are on 8-10 hours a day is probably a good idea. Replacing the lights in the hall closet that runs 20 minutes a week is not. Replace the lights in the ...


7

I received a similar question on my own website a while back, and was surprised when I researched the answer. I thought it was mostly newer technology light bulbs that were recycled to avoid ewaste, etc, but my research indicated that some places will recycle incandescent bulbs as well. If you're in the United States and looking to put them in your curbside ...


7

The best analogy for this is the use of daylight savings time, where in effect people wake up one hour early than they usually do. A study by the US Department of Transport in 1975 (see page 4 of the website), showed that Daylight Saving Time trims the entire country's electricity usage by a small but significant amount, about one percent each day, ...


6

Osram did a good comparative life cycle assessment on bulbs, including incandescent, CFLs, and LEDs. The total life cycle impacts of CFLs and LEDs are both significantly lesser in all categories than incandescent bulbs, meaning that the very best thing you can do with an incandescent bulb is not use it even if it's already been manufactured! They are ...


6

In my opinion, fixing rather than repurchasing is part of sustainability. Of course others believe otherwise, and that's okay. It depends upon the type of lamp, e.g., touch-to-light, mechanical switch, other. My guess is there is a problem with the lamp socket. The first thing I'd do is use my trusty voltage detector (VD) to verify there was voltage in the ...


6

The wattage given on the fixture refers to the maximum that can safely be used. That will be dictated by two things: The internal wiring of the fixture, and the heat that it can tolerate. In reality the additional 6W of the three 42W lamps that you are using is probably not going to be a problem, but it would be wrong of me to advise you that it's OK - you ...


6

The big advantage of GravityLight is that you can pull the weight once and then you have electricity for a relatively long period (I read somewhere it's 30 minutes). This is ideal when you need to have both hands free to do some work. This long period is also a must if you want it to replace the kerosene lamps that are currently used in rural Africa. The ...


5

There are now 60 watt equivalent LED candelabra bulbs available, which use only 7 watts. I bought 12 of them and they are working awesome. Feit PerformanceLED Chandelier / Candelabra Bulbs @ Earth LED


5

Both LED and flourescents can produce 'ideal' lighting conditions for plants. LED Lights are the most efficient measured in lumens per watt, and also in terms of material waste, since they last longer and are smaller. Their biggest current disadvantage is that they are significantly more expensive upfront. Depending on the model and how you figure the ...


4

I would hold a few in reserve in case you ever find a need for them. For instance, I used an 85W incandescent bulb and a steel coffee can to create a small "space heater" for young chicks (chickens). The rest can probably be sold via Craigslist, eBay, or similar. There are still people unwilling to change to more efficient lighting, and those bulbs will at ...


4

There is a xenon (Xe 54) gas inside the bulb and this is inert. Does not harm anything in so tiny amount and it is environment friendly. Bigger xenon lamp should not be breached, because the pressure inside the lamp is different and this they could shatter/explode, but G8 does absolutely nothing, if that happen, but don't do it. To throw it away could be OK. ...


4

What to do with existing stock of incandescent bulbs – use them up or just put an LED in any socket where a lamp burns out? As efficient LED bulbs are widely available the question comes up what is the most economical way to transition, if a household still has some “stock” of previously purchased incandescent bulbs. A white paper published by Forestfern....


4

Please consider donating incandescent bulbs to a support group for diseases that can sensitize some people to light. One disease with fairly widespread support group chapters is Lupus. Lupus has various manifestations, but some individuals with it develop headaches, weakness, and/or rashes when exposed to direct sunlight or fluorescent lights, or even cool ...


Only top voted, non community-wiki answers of a minimum length are eligible