Both Home Depot and Lowes recently dropped their prices on their A-style LED bulbs. Home Depot dropped the price on their Cree 60-watt replacement LED bulbs to $9.97 (from $12.97). Lowes did similar by dropping their Utilitech 60-watt replacement LED bulb to $9.98 as well (from $10.98). Both bulbs are dimmable and have similar efficiency ratings (9.5 and 9.98 watts respectively).
But Lowes did Home Depot one up by introduce two nondimmable bulbs from Utilitech, one a 60-watt replacement for $7.98 and another a 40-watt replacement for $4.98. Realizing that not every application needs dimming capabilities, but people still love the efficiency, instant-on and instant-bright capabilities of LED, Lowes is clearly seeing an opening in the market. Previously, the sub-$10 market for a 60-watt replacement bulb has been pretty hard to find. And at less than $5, the 40-watt even more so. (Ikea does sell a 400 lumen bulb for $4.49, but Ikea is not as geographically available as Lowes or Home Depot.)
This is clearly where the market has been headed. Philips made a name for themselves in the LED market with its award-winning A-style bulbs. But they too have been introducing lower end models to win over general users as well. They introduced both the SlimStyle dimmable model, as well as a semi-directional, nondimmable model, both for just under $10. Both had deep criticism and they tried to trade off features for price. The SlimStyle was a great design in theory, but clearly-cut corners in technology gave it a noticeable CFL-style hum and the cheapness in quality was clearly visible. The semi-directional model made it ill-suited for many applications. And at $10, they didn't compete well with the omni-directional and dimmable Cree model.
In addition, Conserv-Energy at Costco dropped the price of their 60-watt replacement bulb from $10.97 to $8.97. The bulb competes very well in performance with the Cree, but at 13.5 watts, it's not nearly as efficient. Conserv-Energy has also been refreshing their bulb line, so perhaps they are clearing out their inventory in anticipation of a better performing A-style bulb.
And at $5, the 40-watt replacement is clearly a new floor. A similar model at Costco sold in 3-packs for $20, or $6.67 each. Unlike the $5 model, these are dimmable, but clearly the low price point is actually starting to compete with CFLs (which can cost $1-2 each).
It should be interesting to see where this goes. As designs become more simplified, and as chipset become more integrated, and as economies scale up, more and more people should enter the LED market, continuing to drive innovation and drive performance up and prices down. It should be very interesting to see exactly where this goes.
Thursday, April 3, 2014
Wednesday, April 2, 2014
Will LEDs really last 25 years?
This is actually a really good question. Of course, it's easy to be skeptical. 25 years? Considering 25 years ago is when I graduated from high school, it's difficult to imagine them lasting that long. Then again, I still have a CD player I got as a graduation gift. It still works just fine.
It's important to remember that LEDs are fundamentally a different technology than either incandescent, halogen or fluorescent. LEDs are really mini electronics, much like your cell phone or its charger. LEDs (in most cases) must take your high voltage (110 volt) alternating current (AC) and drive low voltage direct current (DC) LEDs. By stimulating the electrons, it creates light and very efficiently.
So an LED bulb must have something called a "driver". This is a set of electronics, much like your cell phone charger, that must do exactly that. The other way it can get around this is by using an array of LEDs in serial. Most LEDs are really small voltage, in the 1-2 volts range. In other words, not only do you have to convert that AC to DC, but you have to get that high voltage down to 1-2 volts. The more the driver must step down the voltage, the more expensive the electronics are. Newer LEDs get around this by putting the LEDs in an array in serial. Think of it this way: If you put two 1.5 volt batteries in serial, you get 3 volts. Much the same, if you put two 1.5 volt LEDs in serial, you can drive it with 3 volts instead of 1.5. Many LED chips put multiple LEDs in serial on a single chip, and multiple chips add up. Many A-style LED bulbs may have 18 chips with 4 LEDs on a chip, and can be driven with voltage similar to 110 volts. This drives the costs down substantially.
So in short, there's two major parts of an LED bulb, the driver and the LED array. If one of those parts fail, the whole bulb will fail.
That said, electronics for the most part are pretty stable. Your cell phone charger is going to work pretty well, particularly if it's from a reputable company. Your LED bulb is much the same.
If one thing is going to kill those electronics though, it's heat. Many LED bulbs are not rated for working in enclosures because they cannot dissipate the heat. Many of the components are rated to last so many thousands of hours at a certain temperature. The higher the temperature, the less time they're rated to last. So check to make sure your bulb is rated to work in an enclosure before you put it in one. (Only bulbs that are rated to work in enclosures can earn the Energy Star label, so that's a good thing to check for.)
Barring the electronics failing, LEDs, like most other lighting technologies, will get dimmer over time, about 1% or less for each 1,000 hours of use.
So that's where the 25,000 hour rating comes from. The electronics are rated to last for 25,000 hours at temperatures the bulb is rated to operate at. The LED array will get dimmer, but instead of failing "catastrophically" (i.e., burning out), LEDs are rated to be past their lifetime when they reach only 70% of their initial brightness. They will still work, but they won't be as bright.
The process of replacing bulbs that are too dim for most use is called "re-lamping". It's common in replacing fluorescent bulbs. Many LED street lights are expected to last for 7-15 years. They are expected to reach their 70% limit in 7-10 years, but can continue to be used for many years after that. For your use, if a bulb gets noticeably dimmer (let's face it, 10-15 years from now), you may wish to replace it, but use the old bulb in a more marginal place, such as a closet where you want instant on but don't need the light to be as consistent.
LEDs also are subject to very fast changing technology. CFLs in particular are a very stable technology. They're about as cheap and efficient as they're going to be. CFL technology such as dimming has been largely replaced by LEDs, as they're similar in price but performance in LEDs in much better and LEDs last longer. The two largest areas of improvement are price and efficiency. Early 60 watt replacement bulbs were $30-40. They now can be had for as low as $8, even without subsidies from power companies. Except them to drop even lower. In efficiency, the early LED bulbs were about 12-13 watts. Now they're as low as 9.5 and dropping. For that reason, I'm telling people not to replace all their bulbs (particularly their CFLs) with LEDs right away. I wait until CFLs burn out, then replace the LEDs I use most with the newer, most efficient bulbs, and then use the older LED bulbs to replace the CFLs that burn out. I have one bulb in my living room that is used more than any other light that has gone from 30 watts, to 26, to 23, to 18. It doesn't sound like a lot, but at 5 hours a day, that difference does save me about $3/year.
So like most electronics, LED lights will probably either last a couple months or a decade or so. Also like most electronics, keep your receipt for the warranty period (3-5 years for most LED lights, I keep my receipts in the same place I keep my extra light bulbs). If it fails before then, get a replacement. If not, you're probably going to enjoy it for a decade or two to come.
It's important to remember that LEDs are fundamentally a different technology than either incandescent, halogen or fluorescent. LEDs are really mini electronics, much like your cell phone or its charger. LEDs (in most cases) must take your high voltage (110 volt) alternating current (AC) and drive low voltage direct current (DC) LEDs. By stimulating the electrons, it creates light and very efficiently.
So an LED bulb must have something called a "driver". This is a set of electronics, much like your cell phone charger, that must do exactly that. The other way it can get around this is by using an array of LEDs in serial. Most LEDs are really small voltage, in the 1-2 volts range. In other words, not only do you have to convert that AC to DC, but you have to get that high voltage down to 1-2 volts. The more the driver must step down the voltage, the more expensive the electronics are. Newer LEDs get around this by putting the LEDs in an array in serial. Think of it this way: If you put two 1.5 volt batteries in serial, you get 3 volts. Much the same, if you put two 1.5 volt LEDs in serial, you can drive it with 3 volts instead of 1.5. Many LED chips put multiple LEDs in serial on a single chip, and multiple chips add up. Many A-style LED bulbs may have 18 chips with 4 LEDs on a chip, and can be driven with voltage similar to 110 volts. This drives the costs down substantially.
So in short, there's two major parts of an LED bulb, the driver and the LED array. If one of those parts fail, the whole bulb will fail.
That said, electronics for the most part are pretty stable. Your cell phone charger is going to work pretty well, particularly if it's from a reputable company. Your LED bulb is much the same.
If one thing is going to kill those electronics though, it's heat. Many LED bulbs are not rated for working in enclosures because they cannot dissipate the heat. Many of the components are rated to last so many thousands of hours at a certain temperature. The higher the temperature, the less time they're rated to last. So check to make sure your bulb is rated to work in an enclosure before you put it in one. (Only bulbs that are rated to work in enclosures can earn the Energy Star label, so that's a good thing to check for.)
Barring the electronics failing, LEDs, like most other lighting technologies, will get dimmer over time, about 1% or less for each 1,000 hours of use.
So that's where the 25,000 hour rating comes from. The electronics are rated to last for 25,000 hours at temperatures the bulb is rated to operate at. The LED array will get dimmer, but instead of failing "catastrophically" (i.e., burning out), LEDs are rated to be past their lifetime when they reach only 70% of their initial brightness. They will still work, but they won't be as bright.
The process of replacing bulbs that are too dim for most use is called "re-lamping". It's common in replacing fluorescent bulbs. Many LED street lights are expected to last for 7-15 years. They are expected to reach their 70% limit in 7-10 years, but can continue to be used for many years after that. For your use, if a bulb gets noticeably dimmer (let's face it, 10-15 years from now), you may wish to replace it, but use the old bulb in a more marginal place, such as a closet where you want instant on but don't need the light to be as consistent.
LEDs also are subject to very fast changing technology. CFLs in particular are a very stable technology. They're about as cheap and efficient as they're going to be. CFL technology such as dimming has been largely replaced by LEDs, as they're similar in price but performance in LEDs in much better and LEDs last longer. The two largest areas of improvement are price and efficiency. Early 60 watt replacement bulbs were $30-40. They now can be had for as low as $8, even without subsidies from power companies. Except them to drop even lower. In efficiency, the early LED bulbs were about 12-13 watts. Now they're as low as 9.5 and dropping. For that reason, I'm telling people not to replace all their bulbs (particularly their CFLs) with LEDs right away. I wait until CFLs burn out, then replace the LEDs I use most with the newer, most efficient bulbs, and then use the older LED bulbs to replace the CFLs that burn out. I have one bulb in my living room that is used more than any other light that has gone from 30 watts, to 26, to 23, to 18. It doesn't sound like a lot, but at 5 hours a day, that difference does save me about $3/year.
So like most electronics, LED lights will probably either last a couple months or a decade or so. Also like most electronics, keep your receipt for the warranty period (3-5 years for most LED lights, I keep my receipts in the same place I keep my extra light bulbs). If it fails before then, get a replacement. If not, you're probably going to enjoy it for a decade or two to come.
Update on LEDs
I helped "green" the houses of my sister and a couple friends. It's been a few years since I greened my own place, and there's been a huge improvement in a lot of lighting technologies. LEDs have become very reasonably priced, especially considering how efficient they are and how long they last. In addition, they work much better in some applications than CFLs ever could.
First off, two things to look closely at are color and lumens. LEDs are typically a very pure white. Like purified water (which is tasteless without the minerals spring water has), we're not used to consuming it in its purest form. Most people prefer a softer light. Color is measured in Kelvin or K. Higher numbers (4000-6000K) are closer to sunlight and typically aren't used unless you need a pure white light. These are great for photography or displays when you really need it to "pop". But most households use a 2700K (the "softest" light, most typically used for gentle lighting like bedrooms and living rooms) or 3000K (a "warm" white, slightly brighter used in kitchens and bathrooms). LEDs try to get close to a soft light but since LEDs run white, they may be a bit brighter than you're used to. The difference between 2700K and 3000K may be more subtle than their incandescent versions. (Note that in LEDs, cooler whites tend to be 5-20% more efficient per lumen.)
The other thing to look closely at is lumens. Lumens is the measurement of a bulb's brightness. Many bulbs (both CFL and LED) use "watt equivalents" to give the user an idea of what the rough equivalent incandescent bulb would be. The issue is that this number is subjective. Even amongst incandescent lights, two bulbs with the same wattage can have a different lumens. Some 40 watt bulbs can be as low as 300 lumens or as high as 500. Because the brighter a bulb is, the more LEDs have to go into it, that means it costs more to manufacture. So some manufacturers will try and pass a lower brightness bulb as a higher wattage equivalent. Look at the lumens and you can compare apples and apples.
LED have some significant advantages over CFLs. For one, they are more likely to be dimmable, or at least not be that much more expensive for the dimmable version. Some may have issues with older dimmers, but modern dimmers may work (those manufactured in the last 10 years) better, or best yet, buy a dimmer specifically made for LEDs. (They'll work better with dimmable CFLs as well. We had issues with dimmable CFLs until we put it on a dimmer built for such.)
Secondly, LEDs are instant on and instantly bright. There is no waiting time for it to get bright. There may be the slightest pause when first turning on, but it's typically less than a second.
Unlike CFLs, they also work in very cold environments. That can make them a good power-efficient substitute for an outdoor light in extremely cold environments. (Most CFLs will start down to about 0 degrees and may take longer to get bright but will work). They don't, however, work in extremely hot environments. Many are not rated for unventilated enclosures. Check the label to see if it's rated for enclosures first before using in such.
I've noticed that the light from one CFL to another isn't always consistent, even when new, so when using them side by side, slight differences may be noticeable. LEDs work better if you need absolute consistency (within a brand and model, of course).
They are the most efficient technology as well. They're typically 10-25% more efficient than CFLs, and up to 83% more efficient than incandescents. They also last the longest, anywhere from 25,000-50,000 hours. That's 22-45 years assuming 3 hours a day, but in applications where they are on 8-12 hours a day (such as offices), that's 6-15 years. Cities are now using them for street lighting because high-pressure sodium lights have to be replaced every 18 months, whereas LEDs are only every 7-15 years, vastly reducing maintenance time as well as saving money in energy costs.
They are also mercury free. Modern CFLs have an absolute minute amount of them (typically 2-4mg or less), but still some people are concerned about them, should they be disposed of improperly.
The other area that is LEDs individually tend to be quite directional. They can be diffused with frosted glass and such, but this can actually be an advantage. For that reason, LEDs tend to work well for flood and spot lighting. For another reason, flood and spot lights tend to be expensive on their own. A spot incandescent or halogen light bulb alone can cost $4-9, and it'll only last about 1,000-2,000 hours, meaning you'll have to replace it in a year with normal use. Between the bulb costs and the electricity savings, LED flood lights can pay for themselves within about a year. I've also noticed that when replacing directional bulbs (like flood lights), you don't necessarily need as many lumens to achieve the same lighting, because the directionality of LEDs mean fewer lumens more concentrated equal the same lighting effect. Buy one to check if it'll work in your application before replacing all of them.
LEDs also scale down much better than incandescents. Small lights such as candelabra lights that are in the 10-40 watt range get way much lower lumens per watt. A 25 watt candelabra may only give off 195 lumens. That can be done in a LED with only 3-4 watts.
Finally, LEDs tend to work well in the presence of vibration. Both incandescent (particularly those not rated for "rough duty") and CFLs work poorly in areas with fans (like an exhaust fan/light in a bathroom) or vibrations like garage doors.
That's not to say they don't have downsides. The cost can be quite high. Some energy companies subsidize them to encourage people to switch, but without subsidies, they can retail for $10-20 and up. The good news is hopefully you'll never need to replace them. They also don't work in all dimmers, particularly older ones, like those manufactured over 10 years ago.
Also, they tend to be sensitive to high heat. Some people have had issues with using flood lights in insulated canisters or in enclosures. Check if they're enclosure safe before using in such an application.
In most cases, if you can use a CFL, use a CFL. Particularly in more marginal applications (rooms that are not on often, like closets), your break-even point is going to be in the years, not months. Some people like the lights of an LED better, but there's clearly an additional cost to them. With some bulbs like A19s, the cost may not be that much more expensive to warrant the advantages (instant on, dimmable, better quality light), and obviously the more you use the lights, the quicker the payback will be. But if the benefits of an LED get you to use them instead of an incandescent, it's definitely worth checking out.
First off, two things to look closely at are color and lumens. LEDs are typically a very pure white. Like purified water (which is tasteless without the minerals spring water has), we're not used to consuming it in its purest form. Most people prefer a softer light. Color is measured in Kelvin or K. Higher numbers (4000-6000K) are closer to sunlight and typically aren't used unless you need a pure white light. These are great for photography or displays when you really need it to "pop". But most households use a 2700K (the "softest" light, most typically used for gentle lighting like bedrooms and living rooms) or 3000K (a "warm" white, slightly brighter used in kitchens and bathrooms). LEDs try to get close to a soft light but since LEDs run white, they may be a bit brighter than you're used to. The difference between 2700K and 3000K may be more subtle than their incandescent versions. (Note that in LEDs, cooler whites tend to be 5-20% more efficient per lumen.)
The other thing to look closely at is lumens. Lumens is the measurement of a bulb's brightness. Many bulbs (both CFL and LED) use "watt equivalents" to give the user an idea of what the rough equivalent incandescent bulb would be. The issue is that this number is subjective. Even amongst incandescent lights, two bulbs with the same wattage can have a different lumens. Some 40 watt bulbs can be as low as 300 lumens or as high as 500. Because the brighter a bulb is, the more LEDs have to go into it, that means it costs more to manufacture. So some manufacturers will try and pass a lower brightness bulb as a higher wattage equivalent. Look at the lumens and you can compare apples and apples.
LED have some significant advantages over CFLs. For one, they are more likely to be dimmable, or at least not be that much more expensive for the dimmable version. Some may have issues with older dimmers, but modern dimmers may work (those manufactured in the last 10 years) better, or best yet, buy a dimmer specifically made for LEDs. (They'll work better with dimmable CFLs as well. We had issues with dimmable CFLs until we put it on a dimmer built for such.)
Secondly, LEDs are instant on and instantly bright. There is no waiting time for it to get bright. There may be the slightest pause when first turning on, but it's typically less than a second.
Unlike CFLs, they also work in very cold environments. That can make them a good power-efficient substitute for an outdoor light in extremely cold environments. (Most CFLs will start down to about 0 degrees and may take longer to get bright but will work). They don't, however, work in extremely hot environments. Many are not rated for unventilated enclosures. Check the label to see if it's rated for enclosures first before using in such.
I've noticed that the light from one CFL to another isn't always consistent, even when new, so when using them side by side, slight differences may be noticeable. LEDs work better if you need absolute consistency (within a brand and model, of course).
They are the most efficient technology as well. They're typically 10-25% more efficient than CFLs, and up to 83% more efficient than incandescents. They also last the longest, anywhere from 25,000-50,000 hours. That's 22-45 years assuming 3 hours a day, but in applications where they are on 8-12 hours a day (such as offices), that's 6-15 years. Cities are now using them for street lighting because high-pressure sodium lights have to be replaced every 18 months, whereas LEDs are only every 7-15 years, vastly reducing maintenance time as well as saving money in energy costs.
They are also mercury free. Modern CFLs have an absolute minute amount of them (typically 2-4mg or less), but still some people are concerned about them, should they be disposed of improperly.
The other area that is LEDs individually tend to be quite directional. They can be diffused with frosted glass and such, but this can actually be an advantage. For that reason, LEDs tend to work well for flood and spot lighting. For another reason, flood and spot lights tend to be expensive on their own. A spot incandescent or halogen light bulb alone can cost $4-9, and it'll only last about 1,000-2,000 hours, meaning you'll have to replace it in a year with normal use. Between the bulb costs and the electricity savings, LED flood lights can pay for themselves within about a year. I've also noticed that when replacing directional bulbs (like flood lights), you don't necessarily need as many lumens to achieve the same lighting, because the directionality of LEDs mean fewer lumens more concentrated equal the same lighting effect. Buy one to check if it'll work in your application before replacing all of them.
LEDs also scale down much better than incandescents. Small lights such as candelabra lights that are in the 10-40 watt range get way much lower lumens per watt. A 25 watt candelabra may only give off 195 lumens. That can be done in a LED with only 3-4 watts.
Finally, LEDs tend to work well in the presence of vibration. Both incandescent (particularly those not rated for "rough duty") and CFLs work poorly in areas with fans (like an exhaust fan/light in a bathroom) or vibrations like garage doors.
That's not to say they don't have downsides. The cost can be quite high. Some energy companies subsidize them to encourage people to switch, but without subsidies, they can retail for $10-20 and up. The good news is hopefully you'll never need to replace them. They also don't work in all dimmers, particularly older ones, like those manufactured over 10 years ago.
Also, they tend to be sensitive to high heat. Some people have had issues with using flood lights in insulated canisters or in enclosures. Check if they're enclosure safe before using in such an application.
In most cases, if you can use a CFL, use a CFL. Particularly in more marginal applications (rooms that are not on often, like closets), your break-even point is going to be in the years, not months. Some people like the lights of an LED better, but there's clearly an additional cost to them. With some bulbs like A19s, the cost may not be that much more expensive to warrant the advantages (instant on, dimmable, better quality light), and obviously the more you use the lights, the quicker the payback will be. But if the benefits of an LED get you to use them instead of an incandescent, it's definitely worth checking out.
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