Let There Be (Fluorescent) Light

Let There Be (Fluorescent) Light
February 2008

A provision in the 2007 energy bill requires lightbulbs to be 30 percent more energy-efficient starting in 2012—a standard that will effectively phase out traditional incandescent bulbs. But why wait? Today’s compact fluorescent light bulbs (CFLs) already use 50 to 80 percent less energy than incandescent bulbs. If every U.S. household replaced just one incandescent bulb with a CFL, the Environmental Protection Agency estimates we would reduce global warming pollution by an amount equivalent to taking more than 800,000 cars off the road.

Most CFLs on the market today offer the same performance, versatility, and light output as incandescent bulbs. Look for the following product information to ensure you find the right bulb for your needs:

* Whiteness: Like incandescent bulbs, CFLs can produce light in many shades of white. Color temperature (or the perceived “warmth” of the light) is measured in kelvins (K); the lower the color temperature, the warmer the color. These temperatures range from about 2700 K (a “warm” yellow-white) to 5000 K (a “cool” blue-white). If the temperature is not listed, look for the terms “warm white” and “cool white” (or “daylight”).

* Brightness: Because CFLs use less energy (as measured in watts) to produce the same amount of light as an incandescent bulb, look for lumens (a measure of light output) on the product label to find CFLs that will match or exceed the brightness of the incandescent bulbs you have been using. For example, a 60-watt incandescent bulb and a 15-watt CFL each produce about 800 lumens. The Energy Star website (see the related links) lists the lumens produced by common incandescent wattages, and CFL packages often mention the equivalent incandescent wattage as well.

* Compatibility: CFLs are available in a wide variety of shapes and sizes, for both standard and smaller (candelabra) sockets. There are even CFLs designed to accommodate three-way, dimmable, motion-sensor, and outdoor fixtures.

CFLs last up to 10 times as long as incandescent bulbs, but because frequent on/off cycles can reduce their useful life, target high-usage areas of your home first (that is, where lights stay on for long periods of time). This will ensure you get the most energy savings right away.

CFLs and Mercury

CFLs do contain a small amount of mercury, so they cannot be thrown out in the trash. However, the mercury in CFLs represents a much less significant environmental hazard than incandescent bulbs because CFLs require much less electricity, and more than half of our nation’s electricity is generated by coal-fired power plants—the largest U.S. source of mercury emissions.

In other words, the average coal-fired power plant emits only 3.2 milligrams of mercury for each CFL running six hours per day for five years, but emits nearly 15 milligrams of mercury for an incandescent bulb running the same amount of time, according to UCS research. The difference far exceeds the approximately five milligrams present inside a CFL. Properly disposing of CFLs ensures the mercury in them remains contained.