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What to Look For When Buying LED Light Bulbs
If you haven’t given the subject of lighting much thought recently, it’s probably because, in common with most people, the phasing out of conventional incandescent light bulbs hasn’t exactly been uppermost in your mind. Which isn’t really surprising; being able to turn on the lights at will doesn’t seem like a big deal. We do it all the time, and depending on the priorities, the whole lighting business is comfortably off the radar.
However, the demise of the incandescent light bulb continues quietly but relentlessly and in less than a couple of years the only products stocked on the shelves will be energy-efficient light bulbs, of which there are two type: CFL (Compact Fluorescent Lights) and LED (Light Emitting Diodes).
Most energy efficient light bulbs available today are CFLs which are about 4 times more efficient than incandescent bulbs (meaning they only waste about 25% of their energy as heat, compared to 90%). However, CFLs are highly disliked by consumers, manufacturers and environmentalists. They have very poor aesthetic qualities (I don’t want you to want them for lighting), they are inconvenient to remove safely thanks to their mercury content; and they are complicated and expensive to manufacture.
On the other hand, LEDs score well on all these points and many more, the most obvious being that LEDs are not only 10 times more efficient than incandescents today, but they double their performance every 18 months or so. The implications of this (known as Haitz’s Law) are staggering; in 3 years we should expect to see LED bulbs 40 times more efficient. No wonder the lighting industry has opted en masse to abandon CFL development and focus on LEDs.
So, should you buy LED bulbs right now? That depends a lot on whether you balk at the listed prices (compared to incandescent and CFL bulbs, LEDs still cost several times more to buy) or whether you can do the math and realize that the savings in electricity consumption you it will more than recoup the investment in the first year or two. And since modern LEDs last more than 50,000 hours (compared to 2,000 for regular bulbs), the return on investment keeps increasing.
Now there are people who will argue that it makes sense to wait until LEDs become cheaper and even more efficient, but then again, if you do the math, you’ll find that it’s actually better to replace perfectly functioning light bulbs with LEDs once in a while so plan to replace them. in a few years, even though they still have years to live. How is it? As the cost of electric lighting is practically equivalent to the cost of electricity; it’s all in the operating costs, not the hardware cost.
So, if you’re thinking about switching to LED lighting, here are some tips on what to look for. First, understand that cheap, low-power LEDs aren’t really capable of replacing most existing lighting; in this field, low cost is a false economy. However, the more expensive branded products are certainly up to the job, look great and can offer some pretty noticeable cost savings.
Second, we’ve all gotten used to classifying light levels by wattage, i.e. 100w very bright, 40-60w comfortable, below 25w a bit dim. This scale does not apply to LEDs. At the moment, a fair estimate is that an LED will produce as much light as a conventional light bulb at 10 times its power, so a 5w LED should be enough to replace, say, a typical 50w halogen lamp.
A more direct means of assessing brightness is brightness, measured in lumens (a standard 40w light bulb produces about 360 lumens). However, luminosity alone is not sufficient to determine the brightness of a light source. The angle of the beam and the “color” of the light are also crucial.
This brings us to a third set of aspects to consider. LEDs are by nature highly directional with a very narrow beam, and until recently have also tended to be on the cool side of things, producing a bluish light. This gives a rather harsh effect with small areas of very bright light but lots of dark spots. Modern high-quality LED spotlights have much wider beam angles (120 degrees for example) that produce an even pool of light and their light color is much warmer. For reference, the color of light is measured using the Kelvin temperature scale where 2000k is called “warm white” and values above 4000k are defined as “cool white”.
So to recap, find out if any LED bulb will be suitable for the application you have in mind by checking the packaging (or if you’re buying from a catalog or online, the product description) for the following items:
- Price and warranty (with LED you really get what you pay for)
- Brand Name
- Brightness (or estimated brightness, i.e. “equivalent to 50 W”)
- Light color temperature (stated as ‘cool’ or ‘warm’ or given in Kelvin – see above)
- Beam angle
- Estimated life (LEDs should last 50,000 hours or more)
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