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Ideas for Energy Efficiency
Making the Appropriate Lamp Selection
A “lamp” is the
term used in the lighting industry to describe what is most commonly
called a light bulb. The key to lighting energy savings lies in the
choice of lamp that we use. There are three primary families of lamps
or bulbs:
• Incandescent
• Fluorescent
• High Intensity Discharge
Incandescent lamps have historically
been the most frequently used in residential applications due to their
low initial cost. Incandescent sources, however, are relatively inefficient
and can add unnecessary electrical costs to our electric bills. Therefore,
incandescent lamps are the least expensive to buy but the most expensive
to operate.
Fluorescent and High Intensity
Discharge lamps have been used most often in commercial and industrial
applications. Their initial cost is more than incandescent lamps, but
they are much more energy-efficient and last significantly longer. Due
to major improvements over the last few years in the color rendering
abilities of fluorescent lamps, and the availability of small fluorescent
bulbs called “compact fluorescent lamps” or “CFLs,”
fluorescent lamps are now a very viable alternative to incandescent
lamps for home lighting use. As an example, for the same amount of electrical
energy, CFLs produce 3-4 times more light than an incandescent bulb.
Incandescent
The three most common types of incandescent lamps are standard incandescent,
tungsten halogen, and reflector lamps.
• Standard incandescent
Known as the “A-type light bulb,” these lamps are the most
common yet the most inefficient light source available. The best option
to achieve energy-efficiency is to replace “A” lamps with
compact fluorescent lamps, which will be discussed below.
• Tungsten halogen
This newer type of incandescent lighting achieves better energy efficiency
than the standard A-type bulb.
• Reflector lamps.
Reflector lamps (Type BR) are designed to spread light over specific
areas and are used mostly in recessed downlight fixtures. Parabolic
aluminized reflectors (Type PAR) are an excellent replacement for the
BR lamps. They have a specially designed reflector that is highly efficient
in pushing light into the space.
Fluorescent
Fluorescent lighting is used mainly indoors – both for general/ambient
lighting and task lighting – and is about 3 to 4 times as efficient
as incandescent lighting. Fluorescent lamps last about 10 times longer
than incandescents. To gain the most efficiency, you should install
fluorescents in places where they will be on for several hours at a
time.
Compact Fluorescent
Compact fluorescent lamps (CFLs) are the most significant lighting advance
developed for homes in recent years. They combine the efficiency of
fluorescent lighting with the convenience and popularity of incandescent
fixtures. CFLs can replace incandescents that are roughly three to four
times their wattage, saving up to 75% of the initial lighting energy.
Although CFLs cost from 10 to 15 times more than comparable incandescent
bulbs, they also last 10 to 15 times longer. This energy savings and
superior longevity make compact fluorescent lamps an excellent choice
for residential use. The new CFLs also produce a better color for the
home.
High
Intensity Discharge
High Intensity Discharge (HID) lamps provide the highest effectiveness
and longest service life of any lighting type. They are commonly used
for outdoor and street lighting, but have very limited applications
in homes. Their residential use is limited to outdoor lighting for driveways,
backyards, etc.
Source: “We’re
Your Personal Trainer for FAT Electricity Bills”, American Lighting
Association
Lighting Controls
Lighting controls are devices for turning lights on
and off or for dimming them. The most useful controls for increasing
lighting energy-efficiency in a home are dimmers, photocells, and occupancy
sensors.
• Dimmers reduce the wattage
and output of incandescent and fluorescent lamps, and increase the service
life of incandescent lamps. Dimmed bulbs will last longer, reducing
bulb replacement costs and frequency. The table below illustrates how
dimming can save electricity.
| Dimming
Your Lights |
Save
You Electricity |
Makes
You Bulb
Last Longer |
 |
10% |
2
Times Longer |
| 20% |
4
Times Longer |
| 40% |
20
Times Longer |
| 60% |
Greater
than 20 Times
Longer |
-
Courtesy of Lutron
• Photocells turn lights on and off in response
to natural light levels. For instance, photocells switch outdoor lights
on at dusk and off at dawn.
• Occupancy
sensors activate lights when a person is in the area and then
turn off the lights after the person has left.
Ceiling Fans
Although ceiling fans cannot
contribute directly to savings on lighting energy costs, they can contribute
significantly to savings on electrical costs associated with space heating
and cooling. Household electrical costs associated with heating and
cooling are in the range of 35-45%. Using a ceiling fan can help to
cool our homes in summer and more efficiently distribute heated air
in winter.
Sources:
1. “We’re Your Personal Trainer for FAT Electricity Bills”,
American Lighting Association
2. “Lutron Dimmers Pay For Themselves”, Contractor Reference
Guide, Lutron Electronics Co., Inc.
3. Source: “Lutron Dimmers Pay For Themselves”, Contractor
Reference Guide, Lutron Electronics Co., Inc.
