Much of a bulb’s longevity depends on how well the electronic components are put together” and “how well it dissipates heat. LED bulbs include circuitry that cuts voltage way down from 110-volts and 220-volts to around 5-to-12 volts, and that converts household alternating current to direct current. The components also include heat sinks.
But what really is the real deal on LED lifetime?
First, let us look on lifetimes for traditional light sources. The lifetime rating you see on the side of the standard incandescent screw-in bulb is defined as the number of hours after which 50% of similar bulbs would have failed completely. This is sometimes called Mean Time Between Failure – MTBF. The bulb in the package has a 50% chance of failing before that time. And failing means no light output, of course. Here’s a look at lifetimes by type:
- Incandescent bulbs can range from 750 hours to 2,000 for “long-life” versions.
- Compact fluorescents (CFL) bulbs have claims of up to 10,000-hour lifetimes.
- Industrial HIF and HID lamps are approaching 20,000-hour lifetimes.
Remember that these are the time period at which they are expected to fail totally. And these lifetime ratings assume ideal conditions; rugged applications or lots of on/off cycles reduce the useful life. Then there is the issue of depreciation (reduced lumen output). The light from most of these bulbs will depreciate substantially (often more than 30%) within the first third of their lives, often causing designers to overlight spaces to compensate. This adds to both the up-front costs and lifetime energy cost of conventional lighting applications.
Now onto LEDs. When we talk about LED lifetime, we mean the period after which the LED light puts out only 70% of its original light. (Note: this is not total failure, just the point at which the system emits less light and a fundamental difference in the definition of ‘lifetime’ largely because LEDs are a fundamentally different illumination technology.) In technical parlance, this is the L70 rating and can range from 50,000 to 100,000 hours based on design and operating temperature. Even after that time period, the LED light will continue to operate for years; just not at 100%.
Light emitting diodes (LED) are not only more efficient than CFLs, but also lasts much longer, sometimes a decade or more. But the high upfront costs means that it’s only during that stretch that the true cost savings start to come into light. Yes this may appear logical but try telling that to consumers who suddenly have to shell out 30 bucks or more for a light bulb when they’re used to paying less than a dollar, then there goes the problem.
So why are they so pricey? And are they going to get noticeably cheaper anytime soon?
The reason why these LED's are costly because of the cost involved in manufacturing them.
To further evaluate, let us go through an analysis of the materials, labor and parts that turning an LED into a light bulb requires. It's actually an integration of some pretty sophisticated technologies. Here’s a quick breakdown:
- Components on the circuit board is often assembled by hand because its still too complicated for factory machines.
- The actual LED wafer can cost as much as $8 a unit.
- The brightest LEDs generate blue light. So in order to get the more natural white glow, manufacturers typically coat the bulb with yellow phosphor, an expensive rare earth metal compound imported from China.
- LEDs additionally require the use of drivers to convert energy into electrical current. This component alone can cost up to $4.
- Although LEDs burn cooler than Edison bulbs, they still need a conducting material to dissipate the heat. The aluminum used to accomplish this can cost as much as $3.
There are also some newer technologies that bulb-makers hope for which will help bring down the cost in due time, some of which include:
- Using larger wafers that would allow LEDs to be built.
- The production of green LEDs that when mixed with red and blue ones create white light.
- Smaller heat sinks that require less aluminum.
It is the long life and the 80%-to-90% reduction in electricity that make LEDs the “great light hope” in the illumination world. The European Commission has ordered a phase out of inefficient, power-hungry incandescent bulbs by 2012. The EC claims that alternatives including LEDs will save enough energy to power 11 million households a year by 2020, cutting CO2 emissions by 15 million tons annually. That, in turn, reduces consumers’ energy bill.
LED bulbs’ super long life combined with their electricity savings gives them a tremendously low cost of ownership compared to traditional lighting.
Though one problem – no one has yet owned an LED for anywhere near 25 years, as the bulbs only recently became commercially available. And early results show that quality - including longevity - is patchy.
At the moment, there are good LED products, but at the same time, also bad products. this makes it difficult for the customer to make a good choice.
To makes things easier here are things you need to look out for and remember when shopping for lights
A standard 60-watt incandescent bulb puts off about 800 lumens. The more lumens, the brighter the light is. LED light bulbs provide many lumens for few watts compared to incandescent bulbs. Since this is the case, it's better to find a bulb that has low wattage but high lumens because it will save you on your energy bill.
You also want to find an LED light bulb that offers a long lifespan. Most offer between 25,000 and 50,000 hours of light. When you look at a Lighting Facts label on the light bulbs, they typically list the lifespan in years. This is based on a standard of using the light for three hours per day each day of the year.
Another thing to consider is the color of the light. Depending on where the light bulb lands on the color temperature spectrum, lights can be all colors: red, yellow, green, blue and shades of white. The shades of white range from warm to cool white. The lower the color temperature, the more yellow your white light will appear. If the light is higher on the color temperature scale, it will appear to cast a cool, bluish hue. Another aspect of the color is the color rendering index (CRI). The higher the CRI number, the greater the number of objects lit by the light bulb that will appear natural.
The bulb should also be UL listed and comply with part 15 of the FCC as a Class B device, meaning it won't interfere with radio frequencies. It's also an added bonus if the light bulb is Energy Star Qualified.
The dimensions and weight of LED bulbs are not the same as a standard incandescent bulb. LED light bulbs are on average a quarter of an inch taller. The average diameter of these LED lights is similar to that of incandescent bulbs but varies depending on the model. LED lights are also heavier than incandescent bulbs, so you'll want to be sure that your light fixture can support the extra weight.
Most LED light bulbs can't be fully enclosed in a light fixture because heat decreases the life of the light bulb. If you plan to use your LED light bulbs outside, you'll first want to verify that they can withstand damp outdoor conditions. If you want to dim your lights with an LED light bulb, you'll need to have one that the manufacturer has specifically designed to perform as a dimmer.
Also consider the beam spread. While incandescent lights put off light in all directions, LED lighting typically sends its light in one direction. The best LED light bulbs that are comparable to 60-watt incandescent bulbs distribute the light around the bulb as well as from the top.
Help & Support
Chances are you won't need to be in contact much with the manufacturer to use your light bulbs.Nevertheless, having a practical return policy and warranty are importance since these light bulbs cost more than incandescent and CFLs. A good LED light bulb should come with at least a three- to five-year warranty.
LED lighting presents a new, more environmentally friendly option. It's long lasting and can save you money over an extended period. These lights are heavier than other lighting options, and the bulb is on average a little taller than a standard light bulb; however, the base can fit in standard light sockets. These lights will keep going long after incandescent and CFLs would have stopped working, and they'll save you money on your electrical bill.
LEDs are easier to control remotely than are traditional bulbs. That means users can switch them on and off and alter their color as well as their brightness - like never before. That, in turn, will lead to new business models in which buyers purchase lighting services rather than bulbs.