Shining new light on light bulbs
Have you shopped your local hardware store and found yourself to be thoroughly confused by all the new types of light bulbs? These days, the multitude of light bulb choices can be dizzying. Let's look at the new technology and guide you through the process of selecting new light bulbs for your home.
The Incandescent light bulb, invented by Thomas Edison in 1879, is the type of bulb that most of us are familiar with. It is defined as a glass globe with a wire filament heated to a high temperature by an electric current passing through it until it glows, thus producing light. Incandescent light bulbs are the least energy efficient, but they have advantages. They are inexpensive, turn on instantly, are available in a variety of sizes and shapes and provide a soothing, warm light with excellent color rendition. However, due to their inefficiency and limited life spans, they are more costly to operate when compared to compact fluorescent lamps (CFLs) and light-emitting diodes (LEDs). Gregory Kay, a master electrician and president of Lightology (www.lightology.com), a Chicago-based lighting design and manufacturing company, notes that incandescent bulbs are being phased out by the Energy Independence and Security Act of 2007. According to Kay, "There is so much wasted energy coming out as heat in an incandescent bulb that it makes a better heater than it does a light source."
A Halogen bulb has a capsule that contains halogen gas surrounding the heated wire filament to increase the efficiency of the incandescence. They cost more than incandescent bulbs but are more energy efficient. Most halogen bulbs have an inner coating that reflects heat back into the capsule which improves efficiency by "recycling" the otherwise unused heat. The filling and coating recycle heat to keep the filament hot, but with less electricity. Halogen bulbs provide excellent color rendition and have a longer life span than incandescent bulbs. Most modern indoor and outdoor flood lights, recessed and track lighting, floor and desktop lamps use halogen bulbs. Some halogen bulbs are dimmable and can be used with timers, but check the package for this feature before purchasing.
The Compact Fluorescent Lamp, or "CFL," became available to consumers about 10 years ago. The CFL bulbs were designed to replace incandescent light bulbs, and most CFLs will fit into light fixtures that currently use incandescent bulbs. The CFL is comprised of a compact ballast and a tube that is curved or folded to fit into the space of an incandescent bulb. Integrated CFL bulbs combine the tube and ballast into one single unit. "Compared to incandescent bulbs, CFLs use about one-third the electricity, and last up to 15 times longer. A CFL costs more, but it can save five times its purchase price in energy costs over the bulb's life span," said Kay. Also available are three-way bulbs and dimmable bulbs with standard bases. The price of a CFL is higher than an equivalent incandescent lamp, but a CFL uses up to three-quarters less energy. Life span averages 6,000 to 15,000 hours.
Light Emitting Diodes, or "LED," are the newest alternative to incandescent bulbs. LEDs are highly efficient, but come with a higher price tag. Buying an LED bulb isn't simple; you must know what to look for. Once you understand the technology and versatility that LEDs offer, you will come to appreciate them. Kay provides a more technical description: "LED and fluorescents both use phosphors to turn a blue light white. The type of phosphor mix determines the color rendering index (CRI) quality of the light. People often dislike fluorescent lighting because the CRI is low and doesn't closely imitate the color rendering properties of natural light. Fluorescents are difficult to dim and basically impossible to turn into a spot light for accent lighting. With LED, you have control over the beam and a variety of dimming options. New power supply and driver technologies offer standard, electronic low voltage (ELV), and 0-10 volt dimming for LEDS. Some LEDs may flicker at the low end of the dimming capacity. Refer to manufacturer specifications and use their recommended dimmers for the bulb and you'll be fine," Kay advised. The final piece of the LED dimming puzzle is the new "warm to dim" LED bulbs. Normal LEDs become visually cooler rather than warmer when you dim them, but there are new LED bulbs that mimic the comforting amber glow of incandescent light bulbs as they dim.
Increased demand and improved manufacturing techniques are lowering the cost of LED bulbs. Utility company rebates have reduced the price of many LED's to under $10, and in some areas they cost just $5 each. While that's still more expensive than the old $.99 incandescent, keep this in mind: An LED bulb consumes one-sixth the energy of an incandescent and lasts up to 25 times longer. Replacing a 60-watt incandescent with an LED equivalent could save $125 or more in energy costs over the new bulb's lifetime. The average homeowner could realize a significant reduction in their electric bill by replacing all incandescent bulbs with LED bulbs.
Today's modern light bulb technology provides longer lasting, energy efficient choices in lighting. The future has arrived and it looks brighter than ever.
Did you know?
The measurement of the color of light is called a Kelvin. The number ranges from 2500 kelvins to 6500 kelvins. A higher "K" number means a cooler light, and a lower "K" number means a warmer light.
Traditional incandescent light bulbs are measured in watts. Modern light bulbs are measured in lumens. Here's how to convert watts to lumens and choose the appropriate bulb for your fixture.
40 watts = 450 lumens
60 watts = 800 lumens
75 watts = 1100 lumens
100 watts = 1600 lumens
150 watts = 2600 lumens
Source: American Lighting Association