Sunday, January 23, 2011


(Please read this article from Scientific American (Jan 15, 2010) and leave your thoughts as a comment, a couple of sentences.  If you want a 4, find another article about light bulbs somewhere, read it and bring some of those thoughts into your comment, another couple of sentences.  Cite your source)

Building a Better Light Bulb

The race is on to develop the modern light bulb, but it may be that the modern light bulb won't be a bulb.

Incandescents -- The Old Standard Bearer

Since the days of Thomas Edison, the incandescent light bulb has been the king of illumination. It works on a basic principle of physics: the hotter a body is, the more light it radiates.
In an incandescent light bulb electrons are forced through a filament to make it so hot that it glows. Because so much of the electrical current's energy goes into heating the filament, incandescent bulbs tend to be very inefficient. And so, acting on today's low-carbon imperative, many people are looking to replace the incandescent with something more efficient.
Others have not yet given up on the incandescent and are working to make that 19th century lighting technology as efficient as its rivals -- the compact fluorescent light (CFL) and light-emitting diode (LED) (both described here).

CFLs -- The (Relatively) New Kid on the Block

Seemingly poised to replace the incandescent, CFLs work on the basis of fluorescence instead of incandescence.
A beam of electrons is sent through a gas causing the electrons in that gas to be excited from their ground, low-energy state to a higher energy state. When the electrons relax back to their ground state, the extra energy is released as light via a photochemical reaction.
Because fluorescence does not depend on heating the gas, CFLs are more efficient than incandescents; typically CFLs use about 75 percent less energy to produce the same amount of light as an incandescent.

LEDs -- Closing Fast

But there are people out there who don't like CFLs -- they don't care for the light quality, the flicker, and the fact that they usemercury. Not to worry; there's an up-and-coming alternative -- commonly referred to by its three-letter moniker LED.
LEDs work on the same fluorescence principle as CFLs but with a twist. Instead of sending a current through a gas, LEDs make use of a crystal semiconductor with varying properties from one end to the other (hence the term diode). Electrons on one end of the diode tend to be in a high-energy state and at the other a low-energy state. When exposed to a current, electrons flow from the semiconductor's high-energy end to its low-energy end, and the energy change shows up as light.
typical LED is slightly more efficient than a CFL, and has the added advantages of a much longer life expectancy and no mercury. That's why many experts believe that while CFLs may be a temporary replacement for the incandescent, the future of illumination will more likely belong to LEDs.

Not So Fast, Mr. LED

While LEDs may eventually win the illumination race, they are nowhere close to the finish line. They're expensive, and the light they give off can be harsh (although advances may have already made some complaints in this area a thing of the past). But still, in terms of giving either incandescents or CFLs a run for the money, LEDs seem relegated so far to primarily flashlights, where long life and low power requirements are at a premium, and outdoor applications, where the harshness of the light is not an issue.

Snow Blind

While we're on the subject of LEDs, here's something folks had not anticipated: LEDs don't work in the snow.
Because incandescents generate heat, they can melt away any snow or ice that might land on them. But the small amount of heat from LEDs means that when they are outside in snowy conditions, they might well get buried. Is this a problem? Potentially yes, since LEDs are being deployed in traffic signals in no small number across the country.
Earlier this month, Joanna Bush of the Department of Transportation in Wisconsin, which has transitioned 90 percent of its state-owned signal lights to LEDs, admitted that "we certainly do see crashes and accidents [during snow storms] attributed to the fact that people can't see the heads," referring to the blocked colored lenses of a traffic signal.
In her view, though, the problem of snow accumulation on the traffic signals "isn't enough to convince us to move over from LEDs."
So while the world awaits a high-tech solution to the problem of snow-obscured LED traffic lights, Wisconsin's DOT, not wanting to sweep the potentially serious problem under the rug, has its own quick fix: "dispatch workers with brooms to clear the lenses." The 21st century meets Disney's The Sorcerer's Apprentice?

Feel the Glow

It could turn out that the next illumination king could be none of these three.
A Welsh company called Lomox is working on a technology based on organic LEDs that would cause walls that are coated with the product and charged with a low-voltage current to glow.
The company claims that its technology will be two and a half times more efficient than the best bulbs available today and will illuminate a dimmer-equipped room in much the way sunlight brightens a room.
Cool. Can't you just see it: Ten years from now, you sit down with your e-reader in your dark room on a snowy winter night and command a robotic broom first to switch on the wall and then to go outside and sweep off the yard lights.

(I found the article by going to the Scientific American website and searching "light bulb")


Sierra said...

Light bulbs are a huge issue today because they are used EVERYWHERE and more and more people are becoming concerned with house hold products being eco-friendly. I think it's weird to think that there are many ways light bulbs are built, but still produce light. That probably means there are other ways out there are still dying to be discovered. I think it's horrible that in Wisconsin there are more accidents because of the light bulbs. They should other switch the bulbs or get people to clean them off. Hopefully in the future bulbs can be eco-friendly, cheap, and work in the snow.

Jennifer's Blog said...

I can understand why incandescent light bulbs are becoming a thing of the past since they are so inefficient. In the age of "going green", there is a move towards energy efficient appliances, cars, and even light bulbs. I use all fluorescent light bulbs at home, but have never thought about the problem of disposing of them once they stop working. The article I found on msnbc discusses this debate. ( (I typed light bulb article in Google and clicked on the one titled "Shining a light on fluorescent bulbs") Unless a new type of lightbulb is developed or the existing ones improved, it seems that we are going to be forced to harm the planet no matter what: either through mercury from efficient light bulbs or greenhouse gases from inefficient ones. It's also amazing how we take things for granted, because until the problem of snow with the LEDs was mentioned, I never thought about how stoplights are always clear of snow. LEDs may be the future in light bulbs, but the glowing wall is definitely the most interesting.

rzacharias11 said...

Light bulbs are a large topic of discussion because of the modern green movement. People are increasingly concerned about man's effect on our planet. Inefficient incandescent light bulbs are concerning because of their limited ability and relatively short life span. According to Mike Yeager in his article "Have you Considered Fluorescent Lighting for Your Home?" (, fluorescent light bulbs are the best alternative for house hold lighting because of their efficiency compared to incandescent. However, even though fluorescent bulbs may be a better alternative for lighting right now, LEDs and other up and coming types of bulbs will make an even better and brighter future.

jharris11 said...

This is a lot like what I found when researching light bulbs. The website I used also mentioned sodium lamps, which can be quite efficient but emit a yellow light. It also talked about how LEDs do not put out enough lumens to light large areas. I’ve heard that CFLs are more efficient and last longer, but tests in our home have proved otherwise. I’m not sure why, but they last about the same as the incandescent bulbs we use. Also, our energy consumption remained the same as before we replaced the bulbs. Maybe change would be visible if we switched them on a larger scale (two hundred light bulbs versus twelve). I am not a fan of LED headlights, either, since I do not have them. I’m sure they are great when you are the one with them, but they are blinding when you drive past them. I cannot see anything when someone with LED headlights approaches, which is very dangerous for me. I think walls that emit light would be really neat to have, especially in school. School lights are very harsh.
My article talks about how incandescent bulbs were going to be banned in 2012. I had not heard of this congressional bill. In an effort to be more eco-friendly, Congress passed an act that bans the sale of incandescent bulbs starting in 2012. However, they now realize that the mercury in CFLs is also dangerous to the environment. Congress has now introduced a bill to cancel this ban. I don’t think the ban is a great idea. Since neither bulb is completely safe, people should have a choice. When a truly eco-friendly and efficient bulb is available, a ban will become more reasonable. ( (typed lightbulb articles into Google search)

Joe Walker said...

With the push towards a more eco-friendly world and a society that wants to create a lesser impact on the environment than it does now, many of our appliances and technology are now being scrutinized for their efficiency. The cheap incandescent light bulb, our primary light source used in most homes today is currently being looked at and redesigned to produce more efficient light. Florescent lights are highly efficient but come with the downside that it contains toxic mercury gas. I believe LED lights are the most plausible replacement for the incandescent light bulb. Producing a minimal amount of heat, most of the energy used in a LED bulb is converted to light, thus the LED light bulb produces a greater amount of light per watt of electricity used. We see that LED lights are now being implemented in other technology including headlights in cars and LED backlit TVs that last even longer than already efficient LCD TVs. The problem comes in making LED bulbs cheaper for the consumer. According to this article on green tech enterprise ( screw in LED bulbs will go for less than 10 dollars in the next 1.5- 2 years. It will be interesting to see whether there will be a shift in the purchase of LED bulbs over cheap incandescent bulbs after the price drops. The question will continue to be whether the consumer will agree to pay more upfront for a more efficient source of light for their homes.

Jessica Z. said...

Light bulbs have come a long way from the inefficient incandescent light bulbs that Edison created. They are continually improving, from the CFLs to the LEDs, and there will surely be more improvements in the future. Improvements are necessary because the incandescent light bulbs are so inefficient, and the green movement has made every person aware of the environmental dangers. CFLs are very common,especially because the incandescent light bulbs are being diminished. I have many CFLs in my home, but I have never thought about the mercury in them. LEDs could be the future, but they need to be less expensive to gain widespread acceptance. According to the article "Energy Efficient Lighting" on the Eartheasy website at, Purdue University researchers have created an inexpensive silicon wafer to replace the "expensive sapphire-based technology." Therefore, LEDs might become inexpensive and brighter with more light bulbs in a cluster. However, they might not work in traffic lights because the lights don't melt the snow. Hundreds and even thousands of people could be killed by snow-covered traffic lights if LEDs continue to be used in traffic lights. CFLs also are very efficent and give off a great deal of lighting. Any improvements to the light bulb, including the new organic LEDs, will be an improvement from the old incandescent light bulbs which can burn up 25% of the average home energy budget, according to the "Energy Efficient Lighting" article.

Joe Szijarto said...

In a society where saving money and saving the environment exist together many eco-friendly and efficient alternatives have been created. Incandescent bulbs were the most optimal way of lighting our homes for nearly 100 years but are very inefficient. Incandescent bulbs will soon be replaced entirely by new and more efficient ways of lighting our homes. I believe that incandescent bulbs will become obsolete within 10 years. Compact fluorescent lights are far more efficient than incandescent bulbs and are fairly cheap to purchase, in my house we use CFL’s in all of our lamps. I can not say that the electricity bill is noticeably lower however you can determine the efficiency of these bulbs just by feeling the comparatively little heat it gives off compared to incandescent bulbs. The only fall back of CFL’s is the mercury gas contained inside the bulbs which make it dangerous when attempting to dispose of and is also not very eco-friendly. LED lights would be the most efficient way of lighting our houses however at the moment they are far too expensive to purchase. The immediate price of these bulbs does not seem to outweigh the money they would save. According to consumer search ( it’s one thing to gamble on a compact fluorescent light bulb that costs $2 to $4, yet another to wonder if an $80 light bulb will last its rated life -- especially because light bulb ratings are based on ideal conditions of temperature and humidity. Also some owners say the light from an LED is too cold and bluish. Owners say they're dimmer than expected, even when used in a light fixture that takes advantage of their directional beam (usually a 60- to 100-degree angle). LED’s seem to be the most efficient bulb to date however there are still some problems that need to be addressed in order for the LED bulb to gain a larger acceptance. I am sure that in the future even better ways will be developed to light an area with even greater efficiency such as the glowing wall stated in the blog post.

Brett Rodgers, BHS said...

As mentioned above, it is quite obvious why more efficient light sources are being created, as most people would rather refrain from spending extra money on bulbs that, during their lifetime, create more heat than light. The purpose of a bulb is not heat, but light. However, I do agree that there still is not an obvious decision as to what to purchase when it comes to newer bulbs. The CFL bulbs take a while to heat up to their full lighting potential, which means if you are doing hands-on work and you need more light, the electricity will have to be on longer to wait for them to heat up before you can begin using the light. LEDs are very bright, but are sometimes too bright. Using LEDs as headlights could be dangerous for other drivers as well as the owner of the LEDs. Most people never realize how much the headlights will heat up, which is excellent in certain weather, especially the weather we get here in Ohio. In my opinion, incandescent bulbs still seem to be the best and fastest alternative for light sources we have available. At least until the other methods are perfected.

griffin said...

Efficiency is a big problem among current light bulbs. Incandescent light bulbs release most of the energy in heat. This means the light bulb is very inefficient at what it is meant to do, provide light. CFL's seem like a good quick fix. A quick fix to a problem that will take longer to solve. LED's seem to be more complicated, and thus more expensive. Unless LED's become cheaper i don't think these will be the fix to lighting inefficiency. The organic LED's being worked on at Lomox seem to be the light bulb of the future. Although i bet these too will be expensive, the long life of these light bulbs will make up for it. Whatever the fix be, current incandescent light bulbs just aren't getting it done.

Taylor said...

My house all uses incancesdents. We debating switching to the LED but the pric was too expensive and we decided to stick with the cheaper ones. The CFLs are not used in my house for the mercury reason. If the lightbulb fell or cracked, one of the animals could try to eat the mercury. We would rather stick with the no mercury also to be safe from it. For putting LEDs we have all older cars so we dont have them in our vehicles. The fact that they dont do good in Snow is bad for Ohio people. They should find a way to get a cover for them that heats up for cars. Its unsafe to not be able to drive without lights in the snow.

Schwartz, Noaki. "It's Lights out for the Incandescent Bulb in Calif - SFGate." Featured Articles From The SFGate. 23 Jan. 2011. Web. 27 Jan. 2011. .

It is smart to reduce the watts that people are aloud to use. But the old fashion people are going to have troubles doing this and not want to. They should keep selling them just a whole lot less of them. They need to reduce the price of others at first to get people to want to buy them. slowly add to the price over time

Kyle' Physics Blog said...

Incancesdents light bulbs are becoming more rare today. The movement of a green world is pushing them away. Today, people turn to the eco-friendly light bulbs (CFLS) and led lights. The CFLs are producing the same or even more photons (units of light) while using less energy the the incandescent light bulbs. Led are "more high tech" the the CFLs and the incandescent light bulbs. They use a semiconductor. The semiconductor has electrons on each side of the diode and one side has high-energy state electrons and the other side has low-energy state. They produce a "stronger" and more efficient light. They also have a longer life then CFLs. The only problem is that they are expensive to make. In Wisconsin, The problem with the accidents will come and go with the evolution of light bulbs. In the article about CFLs (, they state the benifits of the CFL light bulbs. They state that they are more productive and efficient the an incandescent light bulb.

James said...

The future of light bulbs is a highly competitive and also a very debatable topic. There are a few different types of bulbs that we can choose from. LED's,CFL's and organic LED's are all possibilities for the future of light bulbs. An article by Nickie Polson of the Courier-Islander called "shedding some light on the future" explains why these changes are not just possibilities, but they are necessities. The BC Energy Efficiency Act has stopped imports of 75 and 100 watt incandescent light bulbs as of January 1. In 2012 40 and 60 watt light bulbs will also be banned. Turns out that we do not have a choice on if we want to change our light bulbs, we have to. There are plenty of benefits to these light bulbs such as: better efficiency and longer lifetimes of the bulbs. Looks like there will be a brighter future ahead.

Brianna said...

Incandescent light bulbs were once the more popular choice of light bulbs, but today they are not as efficient as our society would like them to be. They have more competition from LEDs and CFLs and hopefully an even better light bulb being created. Even with these types there are problems that are faced. CFLs take too long to reach full brightness and contain mercury. With no special place to dispose of CFLs, they might as well be as harmful as incandescents. LEDs only produce a small amount of heat, which means they will not work well in the snow and they are expensive. Will there ever be a perfect light bulb? For now LEDs are the future, but I do not think they should be used as headlights or street lights.
David Wade is saying that it is the end of incandescent lights and the future for LEDs. The Energy Independence and Security Act is "phasing out" the incandescent light bulbs starting in 2012 when the 100 watt incandescent bulb will be coming to an end. Also, the price for LEDs is expected to drop, too.(

Trisha said...

I think it is interesting that there are so many different types of light bulbs to choose from. With incandescent light bulbs becoming less eco-friendly, some people don't want to use them. LED's are expensive and with the economy down, people don't want those either. The CFL's seem to be eco-friendly since they use 75% less energy than the incandescent light bulbs. The CFL's seem like the best fit since incandescents use the most energy, and LED's are the most expensive. I think in Winsconsin, they need to fix their problem with the LED lights in the snow. If they know that there are more accidents happening because of it, then they should want to try to fix it.

cwolff11 said...

The light bulb keeps reinventing itself in many different varieties. From incandescent, fluorescent, LED and CFL, there are many to choose from. Incandescent are the most basic kind of light bulb, producing more heat than light, making it very inefficient. With the relatively recent "green" movement, there has been a push for more efficient light bulbs that won't harm the environment. More and more people are converting to CFL or LED light bulbs for their efficiency. However I have problems with both. My dad has bought into the idea of CFL light bulbs in our house, which although supposedly more efficient, take longer to light up. After reading the post about LED lights not working in the snow, I question drivers that have LED headlights. That can't be safe for them. Also, it is not safe of considerate to other drivers to have obnoxiously bright lights. The Energy Independence and Secuity Act could spell the end for incadescent light bulbs. Incadescent light bulbs are now in a race against the clock to become more efficient. In an article I found,a company called Deposition Sciences is applying special reflective coating to gas-filled capsules . The coating acts as a heat mirror to bounce the heat back to the filament to produce light. Many people like the features of incadescent light bulbs, such as the color it emits and its compatibility with dimmers. As of when the article was published, no lighting manufacturer had agreed to produce the light bulb, but Deposition Sciences hopes to see their product on the market soon. So it may not be the end for incadescent light bulbs.

My Article: Incandescent Bulbs Return to the Cutting Edge

PhysicsLuke said...

I think it's great that bulbs are becoming more efficient after so many years of inefficiency. Conserving power and energy is vital to saving our dwindling resources and reducing pollution and greenhouse gases that contribute to global warming. LEDs are still a bit too harsh to be used widely on the road right now, but I'm sure they can make a more ocular-friendly version in the future. I had heard about the new LED traffic lights being covered by snow in some cities, turning intersections into crash sites, which should have been recognized beforehand. I do think, however, lightbulb recycling should be more available, as many people simply dispose of lightbulbs, including fluorescents, which have mercury inside that can't have a very positive effect on our landfills, environment, or water supply when broken.

My article on the growth of fluorescent recycling:

Samantha said...

I agree that the incandescent lightbulbs are in efficient. They produce heat, opposed to using all of the energy in the form of light. Since the flourescent bulbs use the atoms picked up from the gas, they use all of the energy produced as light source, not heat. This makes these bulbs more efficient. the problem, though, is the dangers it is causing. If the flourescent bulbs are going to be a hazard, should we really use them? I feel that public safety should be a main concern. I also agree that natural light is the best source of light. We should try to use the natural light more often, rather than coming up with inefficeitn, hazardous forms of light.

Shane said...

It's fascinating on how many different light bulbs that are being invented today. From the LED the the CFL, i don't see there being any problem trying to choose a light bulb to use in the future. It is certain that there will be more types to use in the future that will never need to be changed and i don't see it taking that long for it to happen. ALthough if i were to choose a light bulb to use i would have a tough decision to make because i like how long the LED lasts but the are quite pricey. Although the CFL bulb is a nice change to the incident bulb i probably would not use it because of the mercury in it. There are already more health concerns in a house then there need to be and there is no reason to add more problems to the house or what ever it is that you are using the bulb for. The CFL bulb is nice because its cheep but with the Mercury it is a big turn off so although the LED light bulb is more expensive i would go with it and pay a bit more in the end and get the piece of mind. Depending on how long the LED light lasts i may actually save more money in the long rung even though they are more expensive.

Crazy Physics Man Nick said...

It is crazy just how much the light bulb has evolved over the years. CFLs really take a lot of time to light up and this really annoys me because when i want light i turn the light bulb on and i want light right now!!! Soon in a few years we probably will not even need light bulbs because we will be sooooo advanced that we can find a better source and a more efficient source for lighting!

Emily said...

People today are relying on scientists to create a more efficient and eco-friendly lightbulb. Many people just aren't aware of the many different types of lightbulbs they can use to help save energy. They just expect somebody to hand them the best lightbulb out there without it making a significant dent in their wallet.
In our house we use half compact flourescent and the other half incandescents. In most cases the incandescents look better, like in some light fixtures where you can clearly see the lightbulb. It just looks funny with a swirly lightbulb.
It is good,however, that we have different countries trying different techniques to make lightbulbs more energy efficient. Its creates a drive of competitiveness in these scientists, which will hopefully make it so we can have the newest energy saving lightbulb sooner.
Their ultimate goal should be a lightbulb that could be used in any socket for anything, like a universal remote. It would make things so much easier for everybody and create less problems for those people in Wisconsin and any other snowy states like Ohio. However, people should have just a little common sense to brush off the lights before getting in the car and driving away. We clean off our windows everytime so why not take 2 more seconds to brush off the lights. Sometime,I guess, the snow just piles on when driving, which we have absolutely no control of. Next, they should make little windshield wipers for the lights.
In other articles that I have read, the authors focus heavily on energy saving lightbulbs. The main topic of discusion was CFLs, and barely mentioning incandescents. In this particular article, "How Many Lightbulbs Does it Take to Change the World? One. And You're Looking At It.
By: Charles FishmanSeptember 1, 2006", he talks about the effect that putting these energy saving lightbulbs in every home would have on the environment. He stated that if every home replaced just one incandescent lightbulb with a CFL the energy saved would be enough to power a city of 1.5 million people. That is an amazing number, which should motivate people to try and make a difference a buy more eco-friendly and energy efficient lightbulbs. -

thauser11 said...

When you think about it, it is surprising to think that we only have a few different kinds of light bulbs in all this time, since the light bulb was created in the late 1800s. While the incandescent light bulb was the first and is still used, it is not the best option out there as we have read. CFL bulbs, are more efficient than the typical incandescent bulbs. Since they also require less energy in order to produce the same amount of light as the incandescent bulbs, the only concern a person may have with using the CFL bulbs would have to do with the fact that they contain mercury which may be dangerous in certain situations. While LED light bulbs have a much longer life expectancy, scientists simply need to figure out a way for them to work in the snow and possible another way to lower the price. If this was the case, there would be no reason for people to not use LED bulbs. People also worry about the costs of light bulbs and which is worth their money. In "The Best Light Bulb for Your Money" by Althea Chang (, it discusses the costs, pros, and cons of each type of bulb. It turns out that by switching to CFL or LED bulbs, you could be saving $20,000 over 60,000 hours of use (almost seven years!). While sometimes people only consider the upfront cost of the light bulbs, that is what may be costing them the most. While the incandescent bulb has the lowest upfront cost, it ends up costing you more as they burn out quicker than the CFL's or LED's. Contrastly, the LED bulbs cost the most upfront, but last the longest amount of time between the three types of bulbs. So the choice is yours as to which kind of bulb to buy. However, if you're looking to save money, go for the CFL or LED.