Let There Be Light
As much as 15 percent of a home's electric bill is spent on lighting. Lighting doesn't come alone, however; it brings a lot of heat with it. In the winter the added heat may be acceptable, even desirable, but during the dog days of summer, the extra heat is just one more indoor temperature demon to fight.
As grateful as you might be to Thomas Edison for lighting the world, his incandescent light bulb wastes upward of 95 percent of the energy as heat, making the lights only about 5 percent efficient. That's right — the main reason to flip the switch is light, but really what is being generated is heat. Halogen lights do not fare much better at only 9 percent efficiency.
At 20 percent efficiency, compact fluorescent lights (CFLs) are four times more efficient than incandescent lights. If your home is already equipped with incandescent lighting, rather than unscrewing the bulbs and tossing them, simply replace the five lights used most frequently. These lights are most likely in the kitchen, dining room, living room, over the bathroom vanity, and on the front porch.
By replacing just five incandescent lights with compact fluorescent lights, a standard household could save up to $60 per year. That may not sound like much, but when it's multiplied by all the households in the United States, the grand total is $6.5 billion a year. The pollution equivalent is that this change would offset the same amount of green-house gases as 8 million cars.
CFLs are a little more expensive than incandescent bulbs, but they make up for it in longevity and reduced energy use. Over the span of 10,000 hours, a CFL can cost less than half of an incandescent. In the past CFLs often flickered, but improvements have been made to stop the blinking. New models offer more variety, such as accommodating a dimmer switch.
Even though most people are in the habit of turning off lights every time they leave a room, that's not always necessary with CFLs as they operate within a certain temperature range. You'll see more cost savings if they're used in areas where the lights are frequently left on. If you don't plan to install them in all the light fixtures, consider how much you use a room before you install CFLs.
You need to choose the right CFL for the job. Because CFLs are more efficient, they can operate at a lower wattage. An incandescent light of 40 watts is comparable to a CFL of 14 watts. In addition, when buying CFLs, consider choosing bulbs with a color-rendering index of 80; this will make colors in your home look more natural than bulbs with lower indexes. You can check the label on the package to make sure you're making the best selection.
Here are a few other energy-saving lighting tips:
Avoid opaque light shades. They trap light and require a stronger bulb.
Dark paints and flooring don't reflect light as well as lighter colors.
Clean dust from light fixtures so their light will shine through.
When reading or performing another task requiring focused lighting, turn off background lights and rely on a small focused lamp instead.
Light-emitting diodes (LEDs) have been around for some time and are frequently seen in roadside lighting. Unlike candescent lighting, LEDs produce specific colors. They are comprised of a semiconductor device that converts electron energy to light. Based on the semiconductor materials, the light will be a certain color. Making an LED produce white light is more difficult, but it can be done in a number of ways.
One method manipulates yellow light to appear white. LEDs require much less energy to produce the same amount of luminance, making them appropriate for use with batteries and in places where changing light bulbs is difficult or costly. They are more commonly seen in traffic- and railroad-lighting systems and have been incorporated into flashlight, bike, and motorcycle lights. Because of their relatively high cost, LED lights have not become common in residential lighting systems yet.
