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:
- 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.
The three most common types of incandescent lamps are standard incandescent, tungsten halogen, and reflector lamps.
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.
This newer type of incandescent lighting achieves better energy efficiency than the standard A-type bulb.
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 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 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 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.
|Dimming Your Lights||Saves You Electricity||Makes Your Bulb Last Longer|
|10%||2 Times Longer|
|20%||4 Times Longer|
|40%||20 Times Longer|
|60%||Greater than 20 Times Longer|
– Courtesy of Lutron
- 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.
- 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.
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.
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.