Building Codes Assistance Project

Artificial lighting accounts for almost 15 percent of household electricity use. The traditional incandescent bulb with screw-in fixture currently provides about 85 percent of household illumination. Use of innovative lighting technologies can reduce lighting energy use in homes by 50 to 75 percent. Advances in lighting controls offer further energy savings by reducing the amount of time lights are on but not serving a useful purpose and by turning lights on automatically when and where they are needed.

High performance lighting with optional controls is a key element for a more comfortable and energy efficient home. There are several technologies beginning to be available today that could have the same transformative effect on energy efficiency in homes. LED, or light emitting diode, lighting systems are currently being developed that could reduce the energy use dramatically. While a 60-watt incandescent bulb produces about 1,000 lumens, currently available compact fluorescent lamps (CFLs) produce the same amount of light using only 18 watts, and LEDs now being tested produce the same amount of light using only 4.5 watts of power.

In many homes, lights are often left on when rooms are unoccupied, even with convenient light switch locations. Beyond traditional on-off toggle switches, other more recent innovations offer both indoor and outdoor opportunities to save energy and money:

• Interior Lighting
  
  • Dimmer controls provide inexpensive variable lighting. Incandescent dimmers offer some energy savings when lights are used at a reduced level. Fluorescent dimmers are dedicated fixtures and bulbs that provide even greater energy savings.
  • Occupancy sensors detect activity within a certain area, providing convenience by turning lights on automatically when someone enters a room, and reducing energy use by turning lights off a few minutes after the last occupant has left the room. Two types of occupancy sensors, ultrasonic and infrared, detect sound and heat/motion, respectively.
• Exterior Lighting
  
  • Photosensors sense ambient light conditions to prevent outdoor lights from operating during daylight hours and are useful with all forms of exterior lighting.
  • Motion sensors automatically turn outdoor lights on when necessary (when motion is detected) and turn them off soon after, making them useful for outdoor security and utility lighting.
  • Timers are most effectively used in conjunction with other controls for outdoor lighting because the timer may have to be reset often with the seasonal variation in the length of night.

There are many new and innovative lighting products and design systems - including LED lighting, Dark-Sky compliant exterior lighting, fluorescent lamps, and CFLs -- that are not specified by the model codes that can save energy, money, and enhance occupant satisfaction. For more information, visit www.BuildingGreen.com.

The following section provides examples of these types of code improvement language or methodologies in these areas.

• Require at least 25% of lighting to be high efficacy

  • City of Austin (Texas) Energy Code amending 2006 IECC (applicable to all climates):
    403.11 Lighting. A minimum of 25% of indoor lamps must be Energy Star-compliant high efficacy lamps. Lamps in closets are to be excluded from the 25% calculation. Outdoor luminaires that are permanently attached to a structure must be high efficacy or controlled by an integral photocell.