Light Bulbs…we all need them, but what about all the differences? Remember when you went to the grocery store and there were only 3 types of bread; there was white, wheat and rye? Now, how many different types of bread are available to you at the grocery store? Maybe, 10 times those original 3 types? Well, that is the same pathway of the light bulb.
Light Bulbs…we all need them, but what about all the differences? How confusing are all the options! Remember when you went to the grocery store and there were only 3 types of bread; there was white, wheat and rye? Now, how many different types of bread are available to you at the grocery store? Maybe, 10 times those original 3 types? Well, that is the same pathway of the light bulb.
I have seen a definition of a light bulb as being: It is a removable and replaceable component of a luminaire designed to produce light of thermal origin from electricity to both visible and non-visible electromagnetic energy; made of a ceramic base, metal, glass or plastic, which makes an electrical connection in the socket of a light fixture. WHEW! Really, no one but an engineer cares about all that; what is important to us is, how does it look and how long will it last?
Concerning definitions, let’s get a small thing cleaned up first. A lamp is NOT a light fixture…it is a “bulb”, a light source. Despite the everyday speech of nearly everyone on the planet, there is no such thing as a “table lamp”, unless you are talking about a bulb lying on a table. The so-called “table lamp” is really a “table-supported light fixture”…I know, I know…it’s not a very sexy name, hence everyone uses “table lamp”! Oh well, this is not the first time I have gone against the flow…one of these days I’ll learn better. Back to the matter at hand…
Common to most all light bulbs is the measurement of efficiency, measured in lumens per watt; where “lumens” is the amount of light output per watt of energy input. The bulbs’ life is measured in hours of operation. Another measurement is their “color rendering index” (CRI) measured on a scale from 0 to 100, with 100 being the most ideal light for humans. The lower the wattage, the longer the lamp will last, and the lower the light output; so you should “balance” your light bulb selection…get the right wattage bulb for the necessary illumination needed for it’s location. Note the listed “max. lamp size” for the light fixture you are using, and don’t exceed that wattage limit; you can used less wattage but not more. Don’t buy all the same wattage of lamps or necessarily buy the same wattage you are “used to buying”; consider the location and what illumination is really required; it could save you a lot of money. Besides considering these important items, it is important not to over do the amount of illumination; more light is not necessarily better. Too much light can give you headaches, higher stress, increased blood pressure, and actually decrease worker efficiency. Now, let’s look at the various lamp types you could see in your home.
The standard incandescent lamp or A-lamp, borne out of the experiments of the 1800’s is what we are all used to seeing in our homes; in our businesses, we mainly use fluorescent lighting. Incandescent lamps are very inefficient, less than 3% of the input energy is turned into visible light. Some countries, like Australia and the USA want to ban these lamps within a few years; this, of course, is grossly insane! Why not let the marketplace and capitalism take care of these things naturally instead of unnecessary government interference? Incandescent lamps also produce a lot of heat so you must pay more money to run your air-conditioning systems to remove this extra heat; in a cold climate, that might not be required but in warm climates, it is an added cost burden.
The halogen lamp, is basically an improved incandescent lamp, but with a couple of negatives. They can explode and they can cause burns or even fire much more than a standard incandescent bulb can. Don’t ever touch a halogen bulb whether it is burning or not; allowing oil from your fingers touching the glass will cause short lamp life or explosions.
The fluorescent lamp, is a much more efficient lamp; for the same amount of light output, you put in 1/4 to 1/3 the amount of power. The popular “compact fluorescent lamp” or CFL has been around since the 1980’s. Fluorescent lamps last 10 to 20 times longer than incandescent lamps. Some people don’t like the sometimes-noticeable flutter or the color of light in these lamps…please see the paragraph below on light color; there are color options available to you now. The fluorescent lamp with a high degree Kelvin (4000K or higher) rating is a good choice and looks good; most people don’t object to the high-Kelvin color. While the extremist environmentalists push to ban the incandescent bulbs in favor for these fluorescent lamps, I suppose they have to simply overlook the fact that fluorescent lamps contain a tiny bit of mercury; although there have been horror stories of a home being turned into “a superfund site” over the simple breakage of a single light bulb…a little common sense would be helpful here.
LED lamps, are becoming a good light source, but still have some illumination strength issues to overcome. They have been used in instrument panels since the 1970’s, but as far as space lighting goes, they are need a few more years to develop their output levels. They used to not be able to deliver white light (only colors) but that limitation was fixed, so other lumen output issues will also be improved soon. Their cost is high but they last a long time; for instance, a PAR-38 incandescent lamp might cost you $8 each and last 4000 hours, whereas a LED PAR-38 would cost you $30 each and last 50,000 hours…so at 4 times the cost, you get 12 times longer life…not a bad deal. LEDs also produce little heat and less a lot less power; they are the wave of the future.
There are other types of lamps, namely Mercury Vapor, Metal Halide, High-Pressure Sodium, Low-Pressure Sodium, Carbon-Arc, and Discharge lamps that you really rarely see in residential lighting situations, so I am not going to include them in this particular article. If you have questions on any of these, please drop me an email and I’ll be happy to address your questions.
Now, let us talk about lamp light color; this is critical to most people, but most don’t know anything about it. Color temperature is the characteristic of visible light and is expressed in degrees Kelvin (K). With this system, the higher the number - the whiter the light, and the lower the number – the redder, yellow or pink the light. Incandescent lamps burn “cool”, that is at a lower degree Kelvin, which gives you a more reddish or yellow light. When it comes to most people’s objections to fluorescent lighting, namely the color of light, there are now 4 main categories to pay attention to. “Warm White” (WW) fluorescent lamps have a pinkish color. “Enhanced White” (EW) fluorescent lamps have a so-called neutral color; while “Cool White” (CW) lamps are more of a white light and so are very popular. There is also a “Daylight White” (DW) fluorescent lamp that is a whiter to bluish light. A lot of compact fluorescent lamps (CFL) tend to be more “warm white” and some have a yellowish cast more like an incandescent bulb; for CFL’s I recommend you buy the highest degree Kelvin (K) lamp you can find. The following chart reflects (pun intended) the light color and it’s associated color temperature stated in degrees Kelvin (K); the lower the number, the more pink or yellow the light…the higher the number, the more white the light.
1700K a match flame 5000K typical warm daylight
1850K a candle 5770K sunlight
2800K an incandescent light bulb 5800K typical cool daylight
3400K a studio light or photofloods 6500K daylight
4100K moon light
So, hopefully I have cleared up some of the “muddy water” revolving around light bulbs so you can see better what’s going on (pun intended again). You should be able to look at the packaging of your bulbs and tell better what it is you are buying, and ask yourself the question: Is this the right light bulb for my location?
Oh yeah, please pick me a loaf of bread…I like “Honey Cracked Wheat”.