With incandescent bulbs phasing out, it's easy to get confused by the variety of energy-saving alternatives in stores. Here's how to compare and shop for the new light bulbs.
Most new energy-saving lightbulbs use 25 percent to 30 percent less energy than incandescent bulbs. Photo: AP
Traditionally, we're used thinking about light bulbs in terms of wattage: denominations of 40, 60, 75 and 100 watts are common. But times are changing, thanks in part to new laws requiring manufacturers to phase out incandescent bulbs
for more efficient versions, such as compact fluorescent light bulbs, or CFLs
. As a result, wattage is fading as a measure of energy in favor of lumens
: units that measure the perceived brightness of light.
Manufacturers are going to be making more efficient, lower-watt bulbs, so when comparing different types of bulbs (halogen, CFL, LED, etc.), it's more helpful to look at the number of lumens produced (usually indicated on the bulb packaging) than watts. For example, an 18-watt compact fluorescent and a 12-watt LED bulb can produce lumens equal to a 100-watt incandescent bulb. Use this chart
to help you choose equivalent lighting when purchasing an energy-saving bulb.
With incandescent bulbs phasing out, consumers can replace them with alternatives such as compact fluorescent bulbs and light-emitting diodes, or LEDs. Getty Images
Here are the basics you should know before shopping:
Don't Be Ambushed by Less Output
When shopping for bulbs, you'll often see equivalent wattages indicated on the packaging. These indicate incandescent wattages that produce roughly the same amount of light as the bulb you're buying. However, it's important to note that LED and CFL "equivalents" sometimes do not match incandescent outputs. In one case, I found an LED bulb that claimed to be equivalent to a 65-watt incandescent flood but produced only 575 lumens. In another, an LED bulb for a candelabra produced 30 lumens, but the packaging suggested it was a replacement for a 15-watt, 110 lumen incandescent bulb. LED and CFL equivalents will use fewer watts per lumen and will therefore be more efficient -- but they may not deliver the same amount of light as the incandescent to which you're accustomed. It's best to check lumen output before you buy.
Comparing Efficiency Is Easy
The lumens and wattage will often be given on the packaging or on the bulb itself. To compare bulbs for efficiency, determine the number of lumens the bulb will produce per watt by dividing the lumens by watts. The lower the result, the more efficient the bulb. For example, an 8-Watt, 450-lumen LED bulb produces about 56 lumens per watt (that is 450 divided by 8). A common 40-Watt, 495-lumen incandescent bulb produces only 12 lumens per watt.
Estimating Cost Savings
In my home, we burn recessed incandescent floods in my kitchen ceiling. They burn 65 watts per hour, last for about 2000 hours each, and cost $6 each. I'm considering replacing them with LED bulbs that burn only 15 Watts per hour, last 50,000 hours, and cost $40 each. The cost to operate the incandescents for 50,000 hours is roughly $325. The cost to operate the LED bulb is $75. Add in the price of 23 incandescent bulbs ($138) to the operating cost of the incandescents and the total cost for 50,000 hours is $463. Add the price of the LED bulb ($40) to the operating costs for the LED and the total is $115. The projected savings works out to $348 ($463 - $115).
I burn my lights about 3 hours per day, or about 1100 hours per year, so I would not live long enough to realize the full savings of the LED bulb, which would last me about 45 years! All of this assumes that the cost of electricity and bulbs remain the same. But increases in the cost of electricity or decreases in the cost of LED bulbs (safe bets) would only result in greater savings. It also assumes that the quality of the light produced by long-lasting bulbs will not degrade substantially over the years and force an early replacement.
Remember: It's important to dispose of CFLs the right way, so you can keep yourself and your environment safe. Skip to 1:00 in the video below to learn how:
DIY Product Review: ESL Lightbulbs
Energy Saving Lightbulbs
CFL vs. LED Lights