Reduction Of Outdoor Lighting
On February 1, 2001, Governor Davis issued Executive Order D-19-01 stating, "substantial amounts of electricity are consumed through unnecessary outdoor lighting by retail establishments after business hours, including but not limited to, shopping centers, auto malls and dealerships." The Executive Order requires retail business to substantially reduce unnecessary outdoor lighting wattage during non-business hours.
Reporting Possible Violations
Possible violations of the Governor's Executive Order should be made to your local law enforcement agency such as local police or sheriff's department. Please do NOT use 9-1-1 for reporting violations. Instead, check the pages in the front of your phone book and use the non-emergency phone numbers of your local law enforcement agency.
Strategies Developed by the Energy Commission
These are provided as examples of measures that businesses may want to consider to maintain illumination necessary for the safety of the public, employees, and property, while reducing total electrical usage.
There are four ways in which light (therefore energy) is wasted:
- To have non-essential lighting energized especially after hours. Controls can greatly reduce the amount of energy consumed by exterior lighting.
- Using energy inefficient equipment.
- Sending light up into the atmosphere either by direct light or by reflected light. By using completely shielded (or IESNA cutoff) area or wall-mounted luminaires, light goes down instead of up.
- Over lighting. Not only does over lighting waste energy, it may create light adaptation hazards.
Quality exterior lighting involves selecting the correct equipment for the project, not over lighting, providing uniform lighting for security reasons, and minimizing the glare (non-productive light).
Examples of Measures
The following examples are measures that businesses may consider to maintain illumination levels necessary for the safety of the public, employees, and property, while reducing total electrical usage.
- Evaluate existing exterior lighting systems and identify non-critical lighting. Clearly label all switching devices to save time and help employees identify which lights should be shut-off at specific times.
- Use only energy efficient lamp technologies wherever possible such as metal halide, induction lamps, high-pressure sodium, and linear and compact fluorescent sources. Avoid using fluorescent sources that are not suited for low temperature operation in cold climate zones. Avoid using mercury vapor lighting systems. Incandescent sources should be avoided unless they are integrated with a control mechanism that significantly limits the time that they operate.
- Use IESNA recommended light level ranges. Use the lower recommended values in order lower energy usage, yet stay within recommended values. Abnormally bright lights can create glare and deep shadows, which can make seeing extremely difficult. Illumination ratios between areas should be minimal (e.g., less than 10:1)
- Locate outdoor lighting where it is needed. For example, locate outdoor lighting below tree canopies, not above.
- In parking lots, use efficient and cutoff lighting fixtures that emit no light above the horizontal or into the sky, fixtures that emit no more than 2.5 percent of the lamp lumens upward. Use cutoff lighting fixtures for all lamps greater than 2800 lumens. This will minimize wasted light going up into the atmosphere.
- In signage and retail, use color contrast to attract attention, rather than high levels of illumination. Provide reflective surfaces for lettering or other elements that need to be illuminated at night and illuminate only the lettering, not the background.
There are a number of excellent automatic lighting controls that may be used to turn off exterior lights when appropriate:
- Daylight controls, or photo sensors, used to turn off lights whenever adequate daylight is available.
- Energy management systems and timeclocks, used to limit lighting to within certain operating hours.
- Timer switches, used to turn on lights for only short duration.
- Motion sensors, used to either turn on lights, or turn up lights that have been dimmed, whenever an occupant is present.
Examples of possible uses of lighting controls
- Evaluate and set specific outdoor lighting, as appropriate, to automatically lower or turn off after the close of business to the public, and/or after all employees have left the premises. After business hours, lower light levels to minimal levels, just enough to detect movement and provide sufficient security. Use timers, motion sensors, or an energy management system to turn-off or reduce lighting.
- Some security lighting can be activated with motion sensors so that lights come on only when someone is in the immediate area (consult with local law enforcement). Energy efficient lamp sources ideal for motion sensors include fluorescent and induction lamps. When using "on-off" motion sensors for security lighting, avoid the use of sources that require a period of time to achieve full brightness (HID sources such as Metal Halide or High Pressure Sodium). Incandescent sources can also be an effective source for this type of application since it will only operate a limited time and is not sensitive to temperature effects.
- HID sources can work well in conjunction with motion sensors that offer two levels of lighting (also called stepped ballasts or hi-lo). In these applications, the low level light is provided when no motion is detected. When the motion sensor detects motion, it triggers the lighting to go to the high light level. The hi-lo lighting may be appropriate in parking lots, parking structures, and in areas where safety and security are important.
- Turn off display, advertising, and specialty lights after retail hours (for example after mid-night).
The Lighting for Exterior Environments, PR-33-99 by the Illuminating Engineering Society of North America is one of the most helpful publications on exterior lighting. It can be ordered from their website www.iesna.org or by calling 212-248-5000, extenion 112. Please be sure to refer to publication number RP-33-99. Cost is around $45.
You can also find a wealth of free information on California International Darksky Association website at www.skykeepers.org/index.html. Here you'll find suggested lighting ordinances, actual ordinances, and examples of good and bad outdoor lighting.
A National Equipment Manufacturers Association (NEMA) white paper includes information about common practices on outdoor lighting and how to prevent outdoor lighting problems. The paper can be found at: http://www.nema.org/products/div2/white_papers.html.
For more information about reducing outdoor lighting, please contact:
California Energy Commission
Energy Efficiency and Demand Analysis Division
Nonresidential Buildings Office
1516 Ninth Street, MS-26
Sacramento, CA 95814
Gary Flamm 916-654-2817
Maziar Shirakh 916-654-3839