Chapter 6 Tactics

1. Policy and process changes

• Train/educate staff to turn off lights.
One of the simplest efficiency upgrades a company can make is to institute policies and processes that prevent lights from being left on when office space is vacant. Determine which users of the space should have primary responsibility for turning lights on and off at different times of the day and week and make sure that those responsibilities have been adequately communicated.
Increased coordination among players, from office managers to office occupants and cleaning crews, can often result in decreased energy draw from lighting. Installing a master switch that can simultaneously turn off all lights on a floor will make it easier for the last who leaves to ensure that all lights are out.

• Separate task lighting and ambient lighting.
Separating ambient lighting from task lighting will give employees the flexibility to choose appropriate lighting levels for their workspace, improving lighting quality and reducing unnecessary lighting. Increasing available task lighting and providing individual dimming and on/off controls will allow the users to control and balance the luminance ratios for their task.


• Practice regular lighting maintenance.
It is important to ensure that a regular maintenance and cleaning schedule is in place for existing light fixtures, reflectors, diffusers and lenses. See Table 6.1 for the Federal Energy Management Program's recommended maintenance schedule for commercial lighting systems:

2. Lighting control efficiency measures


There are two types of lighting control devices: devices that enable occupants to control their lighting environment and devices that are designed to take the place of occupant actions. Manual control devices, such as light switches, manual dimmers and window blinds can be directly accessed and controlled by occupants. Automatic control devices, such as occupancy sensors, timers and photosensors, are designed to take the place of occupant actions.

• Install time clocks to automatically shut off lights after hours.
Installing time clocks to turn lighting on and off eliminates the inefficiency of human error in lighting control. Time clocks are best utilized in spaces where occupancy patterns are regular and predictable. A lighting specialist can provide guidance on which time clocks are appropriate for which types of spaces, but generally 24-hour time clocks can be used where occupancy patterns are similar throughout the week and weekend, whereas 7-day time clocks should be used in spaces with occupancy patterns that vary from day to day. Three-phase time clocks may be used to control lighting and HVAC simultaneously.


Payback period: Energy and cost savings will depend on current indoor lighting schedules.

• Install occupancy sensors.
Occupancy sensors can save significant amounts of energy in spaces that are often unoccupied, or occupied unpredictably (stairwells, restrooms, conference rooms, etc.). They are especially effective during hours of the night and early morning when offices have significant unoccupied space that does not require lighting. To avoid performance problems, it is important that occupancy
sensors be positioned correctly to respond to movement anywhere in the space they serve. It is also important to maintain the ability to override the automatic controls, if necessary.


Payback period: According to the State of California’s Green California initiative, the typical payback period for occupancy sensors (before rebates) is two to three years.

Additional information

Additional information on occupancy sensors is available at:
• Wisconsin Public Service, “Lighting: Occupancy Sensors.” Accessible at &page=PA _10.
• FPL E nergy A dvisor, “Lighting: Occupancy Sensors.” Accessible at _10.html.
• Lighting R esearch Center, “Controls.” Accessible at

• Install photosensors, dimmable ballasts and dimming controls in indoor daylit zones.
Photosensors are electronic control units that automatically adjust the output level of electronic lights based on the amount of ambient light detected. In areas that receive varying amounts of daylight throughout the day, photosensor controls can adjust artificial light levels as necessary to supplement available natural light. A continuous dimmer controlled by a photosensor reduces artificial lighting by depending on daylight to maintain an optimum light level. Energy and cost savings will vary widely depending on natural light availability.

Electric lighting dimming controls, which can be either manual or automatic, not only reduce energy, but also provide flexibility. Instead of turning all lights off at any given time, lighting can be dimmed. Fluorescent lamps can be dimmed when fitted with dimming ballasts. Low-voltage tungsten halogen bulbs are dimmed with lowvoltage dimming controls. LED lamps require a dimming power supply in combination with LED dimming controls.

Dimmable ballasts operated in conjunction with photosensors or other control devices achieve a gradual, controlled change in lamp output. Full-power artificial lighting is often unnecessary in areas that receive good natural daylight.

The installation of photosensors with dimming controls and dimming ballasts is most cost effective when undertaken simultaneously with another lighting retrofit where ballasts and controls must be replaced. In this situation, the project cost is limited to the cost of the photosensor installation plus the incremental cost of dimming ballasts and controls over standard ballasts and controls.


Payback period: In a theoretical office with 40 daylit lighting zones and 20 linear fluorescent lamps per zone, installation of dimming ballasts and dimming controls during a simultaneous lighting retrofit would cost an additional $20,200 and would save an additional $3,634 annually in electricity costs, for an adjusted payback period of 5.6 years (assuming a 35% reduction in energy draw by lighting due to dimming controls, an electricity cost of $0.12/kWh and a labor cost of $60/hour).

Additional information

Additional information on dimmable ballasts is available at:
• Lawrence Berkley National Lab, “Retrofit Fluorescent Dimming with Integrated Lighting Control-Economic and Market Considerations.” A ccessible at
• Washington State University.
• “Energy E fficiency Fact Sheet-Daylight D imming Controls.” A cessible at
• “Energy Efficiency Fact Sheet-Dimmable Compact Fluorescent Lamps.” Accessible at
• University of California, Berkeley. “Field Experience with High Frequency Ballasts.” Accessible at
• Lighting Controls Associations. “The next generation of electronic lighting systems:smaller, smarter and greater energy savings.” Accessible at
• Crestron. “Fluorescent Lights-Dimming & Switching.” Accessible at

Additional information on photosensors is available at:
• Lighting Controls Association. ‘Linear Fluorescent Dimming Ballasts— Technology, Methods, Protocols.’ Accessible at
• Washington State University. ‘Energy Efficiency Factsheet—Daylight Dimming Controls.’ Accessible at
• FPL Energy Advisor. ‘Lighting: Lighting Controls.’ Accessible at _40.html.

• Install time clocks or photosensors to control outdoor lighting.
Energy savings can also be achieved through greater efficiency in outdoor lighting. Time clocks or photosensors that turn outdoor lighting on at dusk and off at dawn can avoid energy waste from unnecessary lighting.


3. Lighting source efficiency upgrades

Upgrades to more efficient lighting sources (i.e., lamps, light fixtures, etc.) often yield the most significant efficiency gains in lighting systems. Look for opportunities to replace outdated lighting sources (e.g., incandescents, T12 linear fluorescents) with modern, more efficient sources (e.g., compact fluorescent lamps (CFLs), T8 linear fluorescents, LED, HID). For background information on lighting types, consult Appendix A: Lighting background information.

• Replace T12 linear fluorescent lamps with T8 linear fluorescents lamps with reflectors.
T8 linear fluorescents (narrower in diameter and more efficient than T12 linear fluorescents) are the standard lighting source used in most recently constructed


office space. In older offices however, inefficient T12 lamps may still be in use, and an upgrade to T8s should be undertaken. T12s are typically controlled by magnetic ballasts and T8s require electronic ballasts; therefore, ballasts usually must be replaced when T8s are installed in place of T12s. T8s and T12s come in the same standard lengths, so replacing a T12 with a T8 usually does not require a replacement of the entire fixture. T8 lamps with reflectors and electronic ballasts are about 30% more efficient than T12 lamps with magnetic ballasts (see Table 6.7). T8 lamps also have a longer life than T12 lamps, requiring less maintenance and producing less waste. T5 fluorescents (narrower than T8 in diameter) are more efficient than T8s, but typically require the replacement of an office’s entire lighting system because the


lamps are a different standard length than T8s and T12s. T5 fluorescents should be considered if office space is being renovated, but will not likely be cost effective as a retrofit.


Incentives are also available for “delamping” (permanently removing unnecessary light fixtures). Because T8 lamps have a greater lighting efficacy (measured in lumens per watt), the same quality/brightness of light can often be accomplished with fewer bulbs following a T12 to T8 retrofit. A 10% delamping is typically possible following a T12 to T8 retrofit. An additional benefit of delamping is reduced heat produced from lamps, which lowers building cooling load and energy costs. PG&E provides an incentive of $6.00 for every 4-foot fluorescent lamp that is permanently removed.

Payback period: In a theoretical office where 1,000 4-foot T12 lamps are replaced with 900 4-foot T8 lamps, installation would cost $11,325 and would save $2,109 annually in electricity costs, for an adjusted payback period of 3.6 years (assuming PG&E rebates of $4.25 per T8 lamp installed and $6 per lamp removed, an electricity cost of $0.12/kWh and a labor cost of $60/hour).


• Replace incandescent bulbs with comparable compact fluorescent lamps (CFLs).
In a typical incandescent bulb, 95% of energy is released as waste heat. CFLs are designed to be compatible with traditional incandescent fixtures, but are 60–75% more efficient than comparable incandescent lamps (see Table 6.9) and have an expected life of up to 10,000 hours vs. about 1,000 hours for an incandescent. Replacing incandescent lamps with CFLs will save on maintenance and cooling costs in addition to lighting energy costs. CFLs come in a variety of shapes and sizes and can serve many different lighting needs. For example, variable-output CFLs feature three-way lighting outputs or dimmable lighting. CFLs are viable replacements for incandescent bulbs in almost all office lighting applications.


Payback period: Typical payback for replacement of incandescent bulbs with comparable CFLs is under six months. To generate more specific payback estimates for CFL installation, consult the EPA Energy Star® calculator available at

Additional information

More information on CFLs is available at:
• Alliant Energy “Lighting: Compact Fluorescent Lamps.” (
• CFL purchasing tips: ‘Make the Switch,’ Environmental Defense Fund. (

• Install LED exit signs.
Although exit signs draw a relatively low wattage, they run continuously. A typical incandescent exit sign has an annual energy draw similar to that of a desktop PC. LED exit signs are more energy efficient than incandescent or fluorescent exit signs.


Payback period: In a theoretical office where ten incandescent exit signs are replaced with ten LED exit signs, replacement would cost $430 and would save $4,448 annually in electricity costs, for an adjusted payback period of one year (assuming an incremental cost of $40 per sign, a PG&E rebate of $27 per sign, an electricity cost of $0.12/kWh and a labor cost of $60/hour).

An EPA Energy Star® calculator for savings from exit sign retrofits is available at

• Upgrade outdoor lighting to high-pressure sodium fixtures or metal halide fixtures.
High intensity discharge (HID) lamps provide energy savings of 50–90% over incandescent sources and are well suited to outdoor applications. Costs and rebates: HID prices vary broadly depending on application, but are generally significantly more expensive than comparable incandescent bulbs. PG&E rebates $12.50–$100 for replacing an incandescent fixture with an HID lamp. For details see:

Payback period: Despite the high incremental cost of HID lamps, the wattage reductions achieved when replacing incandescent lamps with HID lamps are significant enough that payback is usually under one year.

Additional information

More information on HID outdoor lighting is available at:
• FPL Energy Advisor. “Lighting: High Intensity Discharge Lamps.” Accessible at _4.html.
• Gardco Lighting. “Saving Energy in Outdoor Lighting.” Accessible at
• Los Alamos National Laboratory. “Los Alamos National Laboratory Sustainable Design Guide,” Chapter 5. Accessible at

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