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General
Lighting Tips
ENERGY
WISE LIGHTING
Lighting
is an element of our home and work environment that affects
our life in many different ways.
Lighting
lets us see to carry out the daily tasks of life; it affects
our comfort and mood, and it can provide safety and security.
Lighting and lighting fixtures also play a major role in
the interior decoration of our homes.
Our
consumption of electricity related to lighting also affects
our budgets, both at home and in our workplaces. The Department
of Energy reports that we spend, on average, 5-10% of our
electric bills on lighting in our homes. In some regions
of the U.S. this amount can be as high as 25% where air-conditioning
is a modest portion of the bill.
ALA
members provide ideas of how you can reduce your home's
electric bill by installing energy-efficient lighting, and
will also provide you with a general overview of home lighting
concepts.
As
a point of beginning, let's look at some basic concepts
that will help us to better understand how these savings
can be achieved.
Energy
Efficiency with Lighting
Saving lighting energy requires either reducing electricity
consumed by the light bulbs and light fixtures or reducing
the length of time that the lights are on. This can be accomplished
by:
- Reducing
the amount of time that lights are on. This can
be accomplished by using dimmers and other lighting controls,
and educating family members to turn off unneeded lights.
-
Lowering wattage, which involves replacing
bulbs or entire fixtures with bulbs and fixtures that
provide the same amount or greater amounts of light with
but with reduced electricity usage. Today, this can be
accomplished most easily by replacing inefficient incandescent
bulbs with incandescent/halogen bulbs or compact fluorescent
bulbs.
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
in their conversion of electrical energy to visible light
and can therefore add unnecessary electrical costs to our
electric bills.
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 "CFL's", 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, compact fluorescent bulbs produce 3-4
times more light than an incandescent bulb.
Incandescent
Options
Incandescent lamps are the least expensive to buy but the
most expensive to operate. Incandescent lamps also have
the shortest lives of the common lighting types. They are
also relatively inefficient compared with other lighting
types.
The
three most common types of incandescent lamps are:
- standard
incandescent
- tungsten
halogen
- reflector
lamps
Standard
incandescent
Known
as the "A-type light bulb," these lamps are the
most common yet the most inefficient light source available.
Note that a larger wattage lamp or bulb may not be the most
energy- or cost-effective option, depending on how much
light is needed. "Long- life" bulbs, with thicker
filaments, are a variation of these A-type bulbs. Although
long-life bulbs last longer than their regular counterparts,
they are less energy efficient. 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. These lamps
are more expensive than standard incandescents but can have
significant impact on achieving greater light output than
standard incandescent lamps.
Reflector
lamps and Parabolic Aluminized 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.
You
can also increase the energy savings for existing fluorescent
lighting by replacing them with a more efficient model (providing
a lower wattage but approximately the same light output),
or by replacing the existing fixture with a more efficient
model.
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
as long. This energy savings and superior longevity make
compact fluorescent lamps an excellent choice for residential
use.
As
previously discussed, CFLs are one of the best energy efficiency
investments available. When introduced in the early- to
mid-1980s, CFLs were bulky, heavy, and too big for many
incandescent fixtures. However, newer models with lighter
electronic ballasts are only slightly larger than the incandescent
lamps they replace. The new CFLs also produce a better color
for the home.
CFLs
come in integral and modular designs. Integral CFLs have
a ballast and a lamp in a single disposable unit. Modular
designs feature a separate ballast that serves about five
lamp replacements before it wears out.
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.
Replacing
Lamps and Fixtures
"Relamping" means substituting one light bulb
for another to save energy. You can decide to make illumination
higher or lower when relamping. But be sure that the new
bulbÍs light output fits the tasks performed in the
space and conforms to the fixture's specifications.
Matching
replacement bulbs to existing fixtures and ballasts can
be challenging, especially with older fixtures. Buying new
fixtures made for new lamps produces superior energy savings,
reliability, and longevity compared with relamping.
Energy-Efficiency
with 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 significantly increase the service life of incandescent
lamps. Dimming fluorescents requires special dimming ballasts
and fixtures, but does not reduce their efficiency.
-
Photocells turn lights on and off in response to natural
light levels. Photocells switch outdoor lights on at dusk
and off at dawn, for example.
- Occupancy
sensors activate lights when a person is in the area and
then turn off the lights after the person has left. They
are popular for areas such as closets and recreation rooms.
Energy-Efficiency with Ceiling Fans
Although ceiling fans cannot contribute directly to savings
on lighting energy costs, but they can contribute significantly
to savings on electrical costs associated with space heating
and cooling. Household electrical costs associated with
space heating and cooling are in the range of 35-45%. Using
a ceiling fan can help to cool our homes in summer, and
helps to more efficiently distribute heated air in winter.
Although
it's difficult to place an exact savings amount related
to the use of ceiling fans, it's an established fact that
ceiling fans can help to reduce electrical costs by creating
greater efficiency in how we heat and cool our home environments.
Especially in summer, it's often more comfortable to turn
off the air-conditioner at night, and use a ceiling fan
at low speed in the bedroom.
Appoint
a Household Energy Monitor
To educate your family members on the importance of energy
conservation, appoint a Household Energy Monitor to turn
off lights, set the thermostat, and to keep the windows/doors
closed if the air conditioning or heater is on. Rotate the
position so that all family members share in the responsibility.
For the energy and money your family saves, have a family
outing while knowing that your family is contributing to
energy conservation.
Lighting
and Electricity Concepts
Wattage, Lumens and Efficacy
Wattage is a measurement of the electrical energy used by
an electrical device, such as a light bulb, but it is not
a measurement of the amount of light being produced. The
measurement of light output from a lamp is the lumen. All
light bulbs have a lumen rating, and it is the relationship
between the lumens being produced and the wattage being
consumed that can provide us valuable information about
the energy-efficiency of a light bulb.
Efficacy
The relationship between lumens and wattage is called efficacy.
This is the ratio of light output from a lamp to the electric
power it consumes and is measured in lumens per watt (LPW).
Incandescent
lamps have an efficacy range from 15 lpw to slightly over
20 lpw. Fluorescent lamps have an efficacy range from 60
lpw to almost 100 lpw. As you can see from these numbers,
the choice of light bulb can have a significant impact on
electrical energy consumption.
Where
To Go
For more information, regarding proper light bulbs and fixtures
to use to help you reduce your lighting energy costs, while
improving lighting in your home, visit our showroom.
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