CFL and LED
The incandescent bulb is rapidly becoming a thing of the past. In 2007, Congress passed the Energy Independence and Security Act, which requires that all light bulbs sold on the market have a 30 percent increase in efficiency over today’s standard incandescent bulbs by 2012 to 2014. Though the new law won’t prevent you from using incandescent bulbs you already own, it does mean that stores will only carry more efficient bulbs that meet those standards from that point on. Lighting can account for up to 20 or 25 percent of a home’s energy costs, so switching can result in savings on your monthly energy bill.
CFL (and fluorescent tube lights) are lit by an electric current that is sent through a tube containing argon and a small of amount of mercury gases. This in turn generates an invisible ultraviolet light, which stimulates a fluorescent coating on the inside of the tube, producing visible light.
- Longevity – With an average lifespan of approximately 10,000 to 15,000 hours, a CFL bulb lasts about ten times longer than an incandescent bulb–which means they need to be replaced less often, making them convenient for those hard-to-reach light fixtures and lamps.
- Efficiency – “CFLs are about four times more efficient than the equivalent wattage of incandescent bulbs,” says Naomi Miller, the senior lighting engineer at the Pacific Northwest National Laboratory in Portland, OR. “So if you take the wattage of the CFL and multiply it by four, that equals the incandescent bulb you would replace. So, for example, a 15W CFL is roughly equivalent in light output to a 60W incandescent bulb.” According to the Environmental Protection Agency (EPA), if every household in America replaced just one incandescent bulb with a CFL, the energy saved would be enough to light 3 million homes and prevent greenhouse gas emissions from the equivalent of 800,000 cars.
- Price – CFL have dropped dramatically in price since they were first introduced to the market in the 1980s. They still cost a little more than incandescents; however, they will pay for themselves after a year or two of use. Because they last so much longer than incandescents, you will continue to see savings on your energy bills throughout the life of the bulb.
- Mercury concerns – Many people are concerned about the mercury in CFL, and with good cause: mercury is a neurotoxicant. The amount in a CFL bulb, however, is smaller than the tip of a pencil. Widespread use of CFL bulbs instead of incandescents will actually reduce the amount of mercury released into the atmosphere, since the main source of mercury emissions are smokestacks from fossil fuel burning power plants, according to the EPA. CFL pose little risk to your family if they break, but proper clean-up is important.
- Some usage limitations – CFL are not dimmable, and they are not efficient in recessed lighting, where they waste about half of the energy they produce. To maximize their efficiency, avoid exposing them to extreme temperatures.
BEST USAGE OF CFL
Many experts view CFL as a placeholder for LED lights, because LED are even more efficient. Currently, CFL come in more shapes and sizes than LED, but with ever-improving technology, many scientists think LED will be competitive within two to three years. For the time being, CFL are the best replacement for incandescent bulbs in most situations; just make sure they are disposed of properly at the end of their life cycle.
LED were first introduced to the market in 1962. They work by the movement of electrons through a semiconductor material. Initially, LED only emitted red light, so their uses were limited to indicator lights and lab equipment. Now, however, they are available in the visible, ultra-violet, and infrared spectrums, which means they now have a much wider variety of uses, including inside your home.
- Longevity – With a lifespan of approximately 25,000-35,000 hours, an LED bulb lasts 2 to 4 times longer than a CFL, and 25 to 35 times longer than a standard incandescent bulb.
- Efficiency – While incandescent bulbs and CFL generate most of their energy in heat, LED are cool to the touch—which translates into less wasted energy. It also means your air conditioner won’t have to run as high in hot weather. LED are more efficient than even CFL: A 16.5-watt LED bulb is equivalent to a 20-watt CFL and a 75-watt incandescent. According to the US Department of Energy, adoption of LED lighting over standard incandescents over the next 20 years will prevent 40 new power plants from being constructed, generate more than $265 billion in energy savings, and reduce lighting electricity demand by 33 percent in 2027.
- Other benefits – LED have other advantages over incandescent lights, including a smaller size and greater durability and reliability. Unlike CFL, LED can also withstand extreme temperatures, and they do not contain toxic mercury.
- Limited usage – LED only produce light in one direction, which make them great for recessed lighting, but not so good in lamps and light fixtures intended to light up an entire room or area. (For example, in many lamps, an LED bulb will end up aimed at the ceiling, rather than offering the 360-degree glow of a CFL or incandescent.) Like the first-generation CFL bulbs, most LED bulbs don’t illuminate instantly when they’re turned on. And it may be difficult at this time to find LED bulbs as bright as the brightest CFL.
- Color quality – Some users may find LED light a bit stark. “LEDs are most efficient when they emit a blue-white color, but many homeowners prefer a warmer (yellower) color of light,” notes Naomi Miller. When selecting an LED bulb, look for a ‘Lighting Facts’ label on the box, she says. It includes a spectrum bar that will indicate whether you’ll get a yellowish or bluish light.
- Expense – According to Miller, “There are good LED products starting to be available, but they may be very expensive, costing $25 to $100 per bulb. It may be a year or two before the product quality improves and the cost comes down.”
BEST USAGE OF LED
LED are great for recessed and outdoor lighting, or lamps that produce a focused beam of light. They also make great indoor and outdoor holiday lights. They are not yet ideal for light fixtures and lamps intended to illuminate large areas of your home.