Energy Efficient Lighting
By Craig DiLouie, LC
What you need to know:
- Federal regulations have eliminated many incandescent lamps
- Consumers now have a choice of halogen, compact fluorescent and LED lamps
- There’s a simple process for obtaining a new lamp that provides comparable performance as your old lamp while saving energy and enjoying longer product life
- Most of the info you need for your decision is on the Lighting Facts label
- The ENERGY STAR label provides assurance you are buying a product that satisfies minimum quality/performance standards
Federal regulations have eliminated a majority of 40-100W screw-in general-service incandescent lamps (light bulbs) from stores. Consumers now have a choice of halogen, compact fluorescent and LED lamps for their incandescent sockets. The Light Logic post provides a simple process for selecting a replacement lamp.
The first step is form factor. Lamps may be omnidirectional (light emitted in all directions), directional (light emitted in a single direction), or decorative (globe, candle-shaped, etc.). The new lamp should satisfy the same purpose and fit the existing luminaire.
Here’s a guide from ENERGY STAR revealing typical lamps used in residential luminaires:
Now go to the store and look at the products. Each will carry a Federal Trade Commission Lighting Facts label on their packaging that looks like this:
While people used to buy incandescent lamps based on wattage, that number now doesn’t mean anything as those standard wattages are no longer available. Now we’re shopping for light output, measured in lumens. Here’s a guide, courtesy of ENERGY STAR:
You’ll want the new lamp to have the right light appearance, which expresses whether the lamp and its light has a warm (orangish-white), neutral (white) or cool (bluish-white) color appearance. Most Americans prefer warm light in living spaces (similar to incandescent light) and cool light in utility and work spaces.
Here’s a guide to color appearance of lamps, again courtesy of ENERGY STAR:
The safest approach is: If you were happy with the incandescent lamp you were previously using, seek the closet equivalence in a new lamp—the same form factor (size and shape), light distribution (omnidirectional or directional), light output and warm light appearance.
After that, we can begin comparing the new lamps that are available. Two important criteria are energy cost and how long the lamp will last.
The estimated annual energy cost on the Lighting Facts label is based on the lamp’s wattage X an assumed 3 hours of ON time per day X an average electric cost of $0.11/kWh, the national average residential electric rate in 2009. Your actual cost, of course, will depend on your actual use and electric rate, but this value on the label provides a useful way to compare relative energy efficiency between different lamps.
The Lighting Facts life rating, shown in years, is the lamp’s rated life divided by an assumed three hours of ON time/day. Longer life means fewer lamp changes—lower future costs and hassle.
If the lamp contains mercury, the Lighting Facts label will show that along with a link to www.epa.gov/cfl to learn more about cleanup and disposal. Compact fluorescent lamps contain mercury, while halogen and LED lamps don’t.
Dimming is an important criterion that isn’t covered by Lighting Facts. All halogen lamps are dimmable, while only some compact fluorescent and LED lamps are. Be sure to check the product packaging to ensure it is dimmable using incandescent dimmers.
After that, get educated about light source technologies and try them out for yourself to see what you like and don’t. Compact fluorescent lamps, for example, offer very good energy savings, but as a diffuse source, its light is somewhat flat, and it may take up to several seconds to reach full light output. LED lamps are instant ON, produce little heat, contain no mercury, and are resistant to shock and vibration. They’re also typically the most expensive option, and some lamps may produce objectionable flicker when dimmed. LED lamps also do not burn out like halogen and compact fluorescent; instead, light output gradually fades away, which should be noted.
When choosing an energy-saving lamp such as compact fluorescent or LED, it’s wise to look for the ENERGY STAR product label on the packaging. ENERGY STAR lamps are independently tested and certified to satisfy performance criteria ensuring the lamp provides comparable light output for 75+% less energy, consistent white light over rated life, consistent light output for most of its life, no flicker while dimming, and a minimum three-year warranty.
By following the above process, you can find a lamp that provides comparable performance as the incandescent lamp you’re replacing while enjoying a lower electric bill and fewer lamp changes over time, with assurance you are using a quality product.
Images courtesy of the U.S. Environmental Protection Agency’s ENERGY STAR program and the Federal Trade Commission.