Here are ways your lighting energy dollars may be wasted:
- Inefficient Light Sources - when the fixture is inefficient in converting electricity to light, using more watts than necessary to produce the lumens.
- Transmission Losses - when dirt or other obstruction blocks some of the light; or when the light source is too far away from what you want illuminated.
- Over Lighting - when more light is used than is needed or when a 'free' source such as daylight is not used.
- Excessive 'On' Hours - when lights are on for no reason.
No-Cost Lighting Improvements
Remove unneeded lamps
Lighting levels often are higher than necessary. Remove unneeded lamps where lighting levels exceed your needs.
Turn off lights when an area is unoccupied
Generally lights should be turned off whenever an area is left unoccupied for any length of time - more than 10 to 20 minutes.
Turn off lights near windows
If your lights can be controlled separately, turn off those nearest the windows whenever there is enough natural light.
Use partial lighting before and after 'public' hours
For those times when employees must work in an area but the 'public' isn't there, consider using fewer lights. You may only need half the lights or lights in a concentrated area, for instance, when stocking shelves and merchandise before opening for business.
Review your outside lighting needs
You may be able to turn off, reduce running hours, or use lower wattage lamps in lighted parking areas, as well as on signs, entrances, walls and landscaping. Be sure to comply with applicable safety and security codes.
Use only necessary safety and security lighting
At night and when areas are unoccupied, make sure the only lights left on are those needed for safety, security or some other specific purpose. Turn off parking area and perimeter security lighting during the daytime. Be sure to comply with applicable safety and security codes.
Make sure automatic controls are working properly
Some of your lighting may be controlled by a time clock, which turns the lights off and on automatically at predetermined times. Just an hour or two each day of unnecessary lighting can add up to substantial energy costs that could be avoided by assuring the timer is doing its job properly.
Keep lighting fixtures clean
Here is a maintenance 'must' - keep lamps and fixtures clean. Dust, grease and other dirt accumulates on lamps, lenses, globes and reflecting surfaces of the fixture, reducing light output by as much as 30%. You should clean your light fixtures every two or three years. In greasy, dusty or smoky settings, or when light fixtures are integrated with the HVAC system, you may need to clean them more frequently.
If your building has a large number of ceiling lights, consider 'group re-lamping' (replacing all lamps in an area near the end of their useful life). Re-lamping can cut lamp replacement labor costs in half when done effectively, and can ensure proper light levels.
Low-Cost Lighting Improvements
Lower your energy costs by 'retrofitting' or modifying your fixtures. It may be necessary when de-lamping or re-lamping doesn't give you sufficient light output. Consider the following when retrofitting your fixtures:
- Install high efficiency ballasts. The new ballasts will use less electricity, and electronic ones will use the least.
- Install reflectors that will 'bounce' more light from the fixtures. Reflectors may enable you to use fewer or lower wattage lamps and still achieve acceptable lighting levels.
- Replace yellowed or hazy lenses, diffusers and globes with new ones that will remain brighter and clearer and transmit more light.
Install more efficient lamps
One of the most effective ways to make lighting more energy efficient is to use the most efficient lamp for the purpose. The more lumens per watt, the more efficient your lamp.
Top 10 Most Energy-Efficient Lamps
1. Low Pressure Sodium
2. High Pressure Sodium
3. Compact Metal Halide
4. Metal Halide
5. Full Size Fluorescent
6. Compact Fluorescent
7. Mercury Vapor
8. Halogen Infrared Reflecting
10. Standard Incandescent
Make downlights more efficient.
Don't use a standard light bulb in a recessed downlights. Use a reflector lamp instead. Because of its design, a lower wattage reflector lamp can project the same amount of light as the higher wattage standard bulb.
Use halogen lamps where appropriate.
When you need a tight beam, such as for highlighting a merchandise display, use a reflector halogen to provide dramatic lighting with significant energy savings. (You may even find you can use a 90-watt halogen PAR instead of a 150-watt conventional PAR0.)
Replace incandescents with compact fluorescents
The conventional incandescent light bulb not only is extremely inefficient, it also has a very short life and must be replaced more frequently, than a compact fluorescent light (CFL). And many CFLs come with rebates. CFLs are available in a wide variety of styles to suit most lighting needs, with reflectors and extenders that can make them fit and work well in a variety of fixtures. They are available either as one-piece screw-in units that incorporate the ballast, or as modular units where the tube can be separated from the base/ballast when the lamp burns out.
Most CFLs have lifetimes of 9,000 to 10,000 hours. Even better, the ballasts in modular units, available in both magnetic and more efficient electronic versions, last 40,000 to 50,000 hours.
How to Save $37 on a Light Bulb
Total costs over 10,000 hours for a CFL vs. incandescent bulb:
|Light Output (lumens)
|Energy Cost @ 9cents / kWh
|Lam Life (hours)
|Cost of Lamp Replacement
|Original Lamp Cost
|TOTAL COST for 10,000 hrs.
Total dollars saved @ 9¢/kWh by using a compact: $37.00
* This is approximate, based on typical cost for a CFL. Price may be lower when buying in quantity.
** Dollars rounded.
Savings in labor to change incandescent bulbs not included.
Source: "How to Reduce Your Energy Costs." Advantage Publications and Insights, Boston, MA 1996.
Retrofit your exit signs
The average exit sign typically contains two or more small incandescent lamps, which use a total of 20 to 50 watts and last from 2,000 to 5,000 hours. Replace these 'energy deficient' lamps with energy efficient replacements.
Install occupancy sensors
Who is turning out the lights when they leave the room? An easy-to-install motion detecting device will turn lights on and off automatically in a private office, restroom or storage area. The three types of sensors include ultrasonic, infrared and ultrasonic/infrared. Many sensors cost less than $100 installed.
How to Achieve Substantial Savings
Rewiring or installing more efficient controls can be a very effective lighting improvement yielding a fast return on investment and savings for years afterward. If your present switches don't give you enough control, consider rewiring and installing additional switches or dimmers. Your electrician can tell you if rewiring will be simple and inexpensive vs. more complicated and costly.