Energy Exchange

By: Elena Craft

A recent article published in the Press Democrat repeats some of the same allegations (as well as some misleading information) that we’ve heard before regarding concerns about Compact Florescent Lights (CFLs), such as:

•  Fluorescent lighting triggers migraines
• Mercury can be released as a vapor if the bulb breaks
• Fluorescent lighting emits  dangerous radio waves

The literature on the impact of CFLs in the marketplace is robust, and we at EDF have responded many times to the concerns raised. We list here some of the most frequently asked questions and provide additional resources for those who wish to investigate CFLs further.

Why are CFLs better for the environment?

CFLs use less electricity than incandescent lights, and therefore result in a reduced consumption of power (a 15-watt fluorescent bulb, for instance, generates the same amount of light as a 60-watt incandescent. This makes a fluorescent bulb about four times more efficient). Since approximately 45% of the energy generated in the US comes from coal, replacing incandescent bulbs with CFLs goes a long way with respect to energy conservation. In addition, since coal-fired power plants represent the largest source of mercury emissions in the US, reducing energy consumption through energy efficiency measures (like replacing incandescent light bulbs with CFLs) results in less mercury that ends up in our lakes and streams from power plants (even if all of the CFLs were to be disposed of in landfills, which we hope they don’t!) As a result, less mercury ends up accumulating in our environment, in wildlife, and in sport fish.

Are CFLs better for your pocketbook?

Because CFLs use less energy, your electricity bill will be lower. The savings vary of course, depending on how many bulbs you install and how long the lights are on. Assuming that the light is on for 6 hours per day and that the electric rate is 11.3 cents per kilowatt-hour, the Department of Energy has estimated that replacing an incandescent bulb with a CFL will save $105 over the life of the light. One public utility in Washington State has estimated that if every American household were to replace the five most frequently used light fixtures or bulbs with CFLs, then each family would save about $60 a year in energy costs. [They consider the five most frequently used light fixtures to be: kitchen ceiling lights, table and floor lamps in the living and family rooms, and outdoor porch lights].  If the average home converts all of the average 40 bulbs in a home from incandescent to CFLs it would roughly triple those savings.

Do CFLs contribute to migraines?

In the past, CFLs might have contributed to headaches. The contribution of CFLs to headaches was a result of the flickering of light produced by the magnetic ballasts that powered fluorescent lamps at about 60 cycles per second. Fluorescent lighting used today uses electronic ballasts that operate at 40,000 cycles per second, resulting in imperceptible flickering to the eye. For more information, see here.

Do CFLs cause electromagnetic interference?

The answer is that it is possible for CFLs to cause electromagnetic interference, but these electric and magnetic fields have not been found to pose a health hazard to the general population.

From EPA’s Energy Star website:

Similar to linear fluorescent lighting and other electronics, it is possible for CFLs to cause electromagnetic interference (EMI). Electromagnetic interference is regulated by the Federal Communications Commission (FCC), and ENERGY STAR includes these requirements by reference for CFLs. In addition, ENERGY STAR requires CFLs to use ballasts that operate at greater than 40 kHz, which limits the potential for interference. Finally, ENERGY STAR requires that the product package clearly state any devices that the CFL has potential to interfere with. This information is usually found along with other statements of known incompatibility with controls and application exceptions.

How much mercury is in the CFL bulbs?

The amount of mercury in CFLs varies, depending on the type and wattage of the bulb. If the bulb is rated as an Energy Star bulb (as most are), then it should contain no more than 5 mg of mercury (5 mg is barely enough to see with the naked eye; for comparison, the amount of mercury in a non-electronic thermometer or thermostat is about 500 mg). In response to concerns from the public about mercury in the bulbs, some members of the Association of Electrical and Medical Equipment Manufacturers have voluntarily agreed to minimize the mercury content in the bulbs. Under the terms of the commitment, participating companies have agreed to cap the average mercury content of CFL models of less than 25 watts at 4.0 mg per lamp. CFL models that use 25 to 40 watts of electricity have capped average mercury content at 5.0 mg per lamp. Environmental Working Group published a list of bulbs that have even lower levels (in the 1-2.7 mg/bulb range) of mercury. You can print out their mercury guide here.

Are there special considerations with regard to cleaning up broken bulbs?

Yes. Because the bulbs contain mercury, there are special considerations with regard to clean-up of a broken bulb. The recommended protocol for cleaning up a broken CFL is the following:

• Have people and pets leave the room.
• Shut-off the central system if you have one and air out the room for 5-10 minutes.
• Carefully place broken bulb in glass jar, sealable plastic bag, or container and place outside (mercury vapors can escape the plastic bag, so don’t keep the bag in the house). Also, if a bulb breaks on the carpet, don’t vacuum it, just pick up the pieces as best you can and dispose of as described above (the vacuum cleaner could cause the mercury to be dispersed). Let the mercury vapor dissipate for a day or two before vacuuming.

You can find more details regarding the step-by-step clean-up instructions on EPA’s webpage.

Why should you recycle CFLs?

Because the bulbs contain small amounts of mercury, it is advised that you recycle the bulbs at any number of collection points, including places like The Home Depot, Lowe’s, and Ikea. Because the bulbs last longer than incandescent, the average home should generate very few bulbs per year. You can find a list of recycling resources here.

So what’s the final conclusion?

Are CFLs the perfect energy solution? No, but they are a big step in the right direction. To help determine what kinds of CFLs are right for you, check out this guide.