How do I choose the right energy-efficient light bulbs?

by Susan Dieker, Green Irene Eco-Consultant
reprinted from Green Irene LLC’s Ask Green Irene Series

When it comes to energy-efficient lighting, many consumers, filled with good intentions, have carted an armload of new light bulbs home, only to see that each bulb presented a different problem – not fitting in non-traditional lamp sockets or under the shades, emitting a cold light reminiscent of a hospital, having to warm up for minutes before being suitable, or not working in a dimmer switch. Choosing to swap incandescent light bulbs for compact fluorescent light bulbs (CFLs) and other energy-saving technologies is one of the easiest and most effective steps toward going green, but can be confounding unless you know what you are purchasing. 

Save Energy and Money

First, understand why you are making the switch. CFL bulbs use 75% less energy than incandescent bulbs and last more than 10 times longer.  While CFLs have a higher purchase price, the energy savings from the decreased energy use and increased life of the bulbs are substantial. Assuming a cost per kilowatt of 15 cents, replacing 44 wasteful bulbs in a medium-sized home can save $3,500 over the life of the first set of energy-efficient bulbs.

Bulb Shapes and Sizes

CFLs are available in various shapes and sizes. The trick is matching the bulb to the task. Most people associate CFLs with a curly-q shape, but a range of traditionally-styled bulbs is available.  Generally, spiral fluorescent bulbs are ideal in fixtures allowing airflow such as lamps, pendants and wall sconces.  However, if your lamp or fixture reveals part of the bulb or if the shade fits onto the bulb, you can purchase CFLs that are covered to look like a standard incandescent. 

Flood CFLs are designed for recessed fixtures and cast light evenly on your task area.  Globes can be used in vanity strips found over bathroom sinks, or in hanging pendant lamps. Standard CFLs do not work on dimmer switches, but special dimmable CFL bulbs are available, as are bulbs for three-way sockets, outdoor use, and for chandeliers and decorative lighting.

Light-emitting diode bulbs (LEDs) are a great energy-saving option, as they use 80% less electricity than comparable incandescents, last 25 times longer (25,000 hours or more) and are manufactured without mercury.  They are relatively expensive, but are very popular for use in decorative lighting, chandeliers, or night lights.

Quality of Light

The light produced by CFLs falls in a range of colors. The most desired color, described as “soft white” or “warm white” (around 2,700 Kelvin), will bring out natural color tones and is ideal for kitchens, bathrooms and home offices. “Bright white” (around 4,100K), a cold or bluish white, produces a clean light good for garages, basements and some reading lamps. While it may be tempting to purchase the bulb labeled “daylight” (5,000K) or “natural”, this light is best for commercial spaces such as galleries, stores and restaurants.

A Few Words about Mercury

A single CFL bulb contains about 5mg of mercury, though premium, very low-mercury CFLs are also available. To put this in perspective, old “under the tongue” thermometers contained 500mg of mercury. When a CFL is in use and intact, no mercury is released. 

For disposal, the EPA recommends recycling old CFLs. Some national chains, like Home Depot, recycle CFL bulbs for free. If a CFL breaks, simply air out the room, carefully sweep the pieces into a plastic bag, and throw it away.

Be Even More Efficient

After you make the switch to CFLs, kick your efficiency up a few more notches. Add task lights to desks, tables and night stands so that if you are working at your desk or reading, the entire room isn’t illuminated. Incorporate more daylight into your home by opening blinds or installing solar tubes, which are like skylights in tube form.  Of course, keep lights off during the day or remove some bulbs from a fixture if it has more than are needed. Always use the lowest wattage needed for a task, as that saves energy as well. Train yourself and your family members to turn out the lights when leaving a room or install room occupancy sensors that do this automatically.

These simple steps, when combined with a light bulb swap-out, are a great way to reduce the energy you use to light your home. If you’d like to receive a free guide to Energy-Efficient Lighting, or are interested in seeing the many types of energy-efficient bulbs in your home, send me an e-mail. I’d be happy to help you learn more about savings that will have a positive impact on both your wallet and our world.

Green Irene consultants help communities implement green solutions to achieve healthier, safer, and more sustainable lifestyles. Visit www.greenirene.com/SusanNewburyportArea for more information.

 

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