ADVANCED LIGHTING SYSTEMS
Eric E. Richman
Pacific Northwest National Laboratory
Lighting accounts for almost 32% of the energy used in commercial buildings, and energy codes are
becoming more rigorous as the need to reduce national energy consumption increases. With the high
impact of lighting energy consumption in buildings, it is a practical target with both easy to implement
and more complex solutions that could yield substantial results. Advanced lighting systems should be
considered in all Federal facilities, both new construction and existing buildings.
There are a number of lighting technologies that have been available for decades, but were not often
implemented in Federal facilities due to either budgetary constraints, lack of guidance, undocumented
results or other application issues. Other technologies in the lighting field are emerging with potential for
even greater energy savings if used in the right applications.
Most commercial facilities in the US are bound by energy codes, most of which are based on existing
standards such as ASHRAE/IES 90.1 which was most recently published in 2007. The Energy
Conservation Standards for New Federal Commercial and Multi-Family High-Rise Residential Buildings
and New Federal Low-Rise Residential Buildings was established with the requirement for new Federal
buildings built after January 3, 2007 to achieve a level of energy efficiency 30% below the ASHRAE
90.1-2007 standard. This rule does not have specific lighting connected load reduction requirements,
but increasing lighting energy efficiency can be a substantial part of reaching this goal.
Lighting Project Basics
When considering energy retrofits or new construction options, there are some basic principles and
application realities that need to be considered. Ensuring that these basics are considered will improve
the potential success and effectiveness of the project:
 Apply effective cost analysis - As with all technological advancements, some are more cost
effective than others and it is important to perform a financial analysis to determine if there will be
sufficient savings to justify the project. Initial simple calculations that consider differences in
technology wattage as estimates of energy savings compared to cost are useful. However, the
variables of possible changes in operational hours, direct control savings, and any possible
maintenance savings should also be incorporated into the analysis for final decisions. It is often
control applications and related operational changes that provide the majority of savings.
 Ensure effective lighting quality - It is critical to ensure that the proposed new lighting technology
offer an effective match to the needs of the space or area. This includes maintaining appropriate
light levels as well as ensuring user satisfaction of the lighting environment.
 In some cases spaces may be over-lit and reductions to proper levels should be part of the
proposed change when energy savings are important. When considering changes, verify the
expected use of the space as far into the future as possible to ensure that chosen project light
levels will be appropriate.
 Present and promote retrofit projects positively as new and more energy efficient. Lighting
education is important so that occupants will understand that reducing energy consumption is
important and they will be more accepting of any changes in the case of retrofits. The human visual
system does not actively notice changes of up to 20% reductions in light levels when done
gradually or when absent. Clean refreshed systems will appear brighter even if illumination and
energy are reduced.
Energy and Water Conservation Design Requirements for SRM Projects
Lighting Technology and Control Strategies by Application
Each interior space type or exterior area has different lighting needs and functional characteristics that
define potential lighting efficiency improvements. These sections provide practical guidance on
technologies and appropriate applications that will reduce energy are generally cost-effective.
High bay interior lighting
High bay retrofits can be a cost effective investment in federal building renovations due to their typically
large lighting loads. Daylighting is an effective solution for new construction in most climates in the us.
Daylighting is not as easy to achieve in retrofits as new construction, but should still be considered
when the conditions are appropriate. In both new construction and retrofit, it is useful to understand
which current technologies may be inefficient and could successfully be replaced with a new lighting
system.
 High Pressure Sodium (HPS) is a common technology in high bay areas and is very efficient. Its
drawbacks include yellowish color and the inability to be dimmed or restarted very quickly. If better
color or control capability (daylight or occupancy based control) are desirable, consider Pulse Start
Metal Halide (MH) technology. At higher wattages, the MH can be an efficient source and provides
closer to white color, even though it also takes time to warm up to its full light output.
 Incandescent and older Probe Start (older starting technology) metal halide (MH) lamps are among
the least efficient and commonly installed high bay lighting system. They should be replaced either
with Pulse Start MH, T8, or T5 fluorescent lamps with electronic ballasts for improved energy
savings. The use of T8 or T5 technologies can also provide dimming capabilities for daylight
savings and allow occupancy based switching for additional savings.
 Pulse start (more advanced starting method) MH lamps over 400W are very efficient and are
capable of providing sufficient light in spaces with ceilings greater than 25 feet.
 Use T8 or T5 fluorescent lamps in place of metal halide lamps using fewer than 400W because they
generally have a greater efficacy.
 The ideal energy efficient lighting solution for most buildings would include hybrid lighting systems
with Skytubes, photosensors for daylight harvesting, and dimmable fluorescent high bay
luminaires. Do not use Skylights in buildings located in extremely cold climates because of larger
skylight thermal losses and any daylighting systems in buildings those with primary hours of
operation only at night when daylight is not available.
Exterior façade and security
Exterior Lighting Is Often Neglected When Interior Lighting Renovations Take Place. Some Low Profile
Lighting For Pedestrian Pathways And Landscape Lighting Typically Use Low Wattage Incandescent
Lamps And Can Be Overlooked During Energy Analysis. Individually These Luminaires May Have A
Minimal Impact On Energy Consumption, But Collectively They Can Have A Large Impact On Actual
Energy Usage.
 Incandescent lamps have very low light output for the power they consume and relatively short
lifetimes. LEDs should be installed in place of incandescent lamps whenever possible. There is a
growing selection of solid-state light emitting diodes (LEDs) that are well suited for exterior use.
LED driven step lights, bollards, parking pole lights, and wall mounted security lights provide low
wattage lighting with extended lamp life and lower lighting maintenance, especially in cold
applications, such as exterior.
 HPS lamps are very efficient, but they do not render colors well. If HPS lamps are presently
installed, replacing them will likely not be cost effective. Despite their high efficiency, installing HPS
lamps in place of MV or probe start metal halide is not recommended because of the drastic change
in color. Pulse start metal halide lamps are very effective for exterior lighting, but cannot be
operated on an occupancy sensor due to their extended warm-up time.
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Energy and Water Conservation Design Requirements for SRM Projects


Regardless of the technology used for exterior lighting applications, an exterior photocell or
astronomical time clock should be used to ensure that unnecessary lighting is not on during daytime
hours.
Façades and many security areas are often over-lit compared to industry recommended (see
IESNA) and current practice and could provide an opportunity for effective energy reduction
retrofits.
There are some common misunderstandings regarding security lighting and light levels. Many people
believe that brighter exterior spaces provide a greater deterrence for crime, where it is actually more
uniform lighting that is better for surveillance cameras and minimizing the amount of places a criminal
could remain undetected. Although not often mentioned, the absence of glare helps security officials
and witnesses to be more aware of their surroundings, and any questionable activities that might occur.
Lighting color is also important for facial recognition, making some efficient technologies such as
sodium lamps a less effective solution for security lighting.
Exterior parking/street lighting
For existing parking lots, using the current poles will likely be the only practical option for implementing
a cost effective lighting retrofit. Pulse start mh lamps are a good replacement for mv, probe start mh,
and low-pressure sodium (lps) since their optical systems are designed similarly and provide a
comparable lighting distribution and often better color. Led luminaires should also be considered if the
distribution can be matched to accommodate the existing pole spacing.
In new construction, LED luminaires should always be considered. The low wattage luminaires are
designed to provide excellent lighting at night and, unlike MH and HPS lamps, they do not require time
to warm up and can be used with an occupancy sensor after a building’s typical hours of operation to
further increase energy savings. All exterior lights should be controlled either with a photocell or
astronomical time clock for the most effective level of control.
General interior spaces
Existing spaces may include several standard lighting technologies that could easily be replaced with
more energy efficient options. In each case the lighting needs of the space must be considered for
effective application of newer technologies. Table 1 below lists common inefficient situations and offers
recommendations for improvements in lighting technology and controls.
Table 1. Interior Lighting Recommendations.
Existing
Technology
Recommended
Improvement
Technology
Recommended (ideal) Upgrade
Dos and don’ts
(for ideal upgrade)
Recycle all fluorescent
lamps
Do not use dimming
controls unless the
ballast is specified for
dimming operation
Note: CFLs are an improvement from incandescent lamps but because of their diffuse nature might not provide strong enough
directional light for some applications. If a narrow directional light is needed, look into replacing incandescent with low wattage ceramic
metal halide lamps.
Manual Switches Occupancy Based
Apply PIR for small spaces, ultrasonic where there might be Do not use vacancy
Sensors:
sensors where being
minimal movement or no direct line-of-sight. Use vacancy
Occupancy Sensors (auto- sensors where manual-on can eliminate false starts such as able to turn lights back
conference rooms, private offices with daylight, etc. Ensure on might be an issue if
on, auto-off)
they turn off accidentally
that sensors are calibrated to perform as required – test
Vacancy Sensors
units to eliminate false starts and time-outs
(manual-on, auto-off)
Incandescent
Compact Fluorescent
(screw-base)
Low wattage MH
Replace standard incandescent applications with CFL
luminaires with integrated ballast (pin-based). For locations
where luminaires cannot be replaced use screw-based
replacement CFLs. For locations with higher ceilings such as
lobbies, low wattage MH technology may be appropriate and
provide longer life
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Energy and Water Conservation Design Requirements for SRM Projects
Existing
Technology
Recommended
Improvement
Technology
Recommended (ideal) Upgrade
Dos and don’ts
(for ideal upgrade)
Note: Occupancy sensors are a simple and effective upgrade to the lighting system that can yield great energy savings. Ensuring that
lights in conference rooms, restrooms, lunchrooms, copy rooms, and other shared spaces are off when not in use has shown a
significant reduction in lighting energy consumption.
Over-lit Spaces
T8 or T5 lamps with
Redesign lighting system with efficient T5 or T8 luminaires to Consider de-lamping
appropriate electronic
achieve appropriate light levels, or replace ballasts with
only as a last resort
ballasts
option
ballasts of a different ballast factor that will lower lights to
provide only what is recommended and necessary (refer to Integrate daylighting
lower ballast factor
IES guidelines for recommended light levels)
ballasts
controls if there is
sufficient daylight
Note: It will be important to educate existing occupants to transition to lower light levels if needed. There are current theories that
suggest spectrally enhanced lighting (more bluish light), will allow light levels to be dropped even lower than current IES
recommendations. While this idea may have merit, it has not been verified to provide superior lighting environments than standard light
reductions in field applications.
Ensure that photocells
Integrate a daylight harvesting system with photocontrols
Daylit spaces
Daylighting step or
are located to provide
and dimmable fluorescent luminaires. Incorporate vacancy
continuous dimming
accurate sensing of
sensors where manual on is practical. Commission the
controls and
photosensor(s).
system to reduce light output in response to daylight. Use a useful daylight
ballast with the capability to continuously dim the lights in
Commission the system
Vacancy sensors (to
consistently occupied spaces, or step dim the lights in
to ensure effective
achieve further savings
during unoccupied hours intermittently occupied spaces. Daylighting controls will only operation throughout the
be cost effective when there is sufficient daylighting
day
and allow occupants to
leave lights off if desired) available.
Note: Daylighting can usually be cost effective in new buildings where skylights and windows are correctly sized and located and
appropriate controls can be integrated. The conditions in existing buildings for retrofits make it more difficult to implement the most
effective daylighting strategies but larger open spaces are still a prime candidate for daylighting control.
Specific technology application notes
The most efficient technology does not always mean that it is the best choice for a particular
application. Each application has a number of lighting solutions that can achieve the pre-determined
energy savings goals if used in the right circumstances and with the right control strategies. Some
technologies might exceed the energy goals, but not provide sufficient color rendering or be operable
with the ideal control choice. In order to achieve maximum energy savings, it is important to have a
general understanding of lighting technologies and controls.
Lighting controls
Using energy efficient light sources is important to energy reduction, but implementing appropriate
lighting controls is just as important to optimizing the lighting system for maximum savings.
Occupancy Sensors ensure that lights are turned off when spaces are unoccupied and provide great
reductions in energy consumption in most facilities (please see occupancy sensor template for more
detailed instruction).
 Passive Infrared (PIR) – detects field-of-view motion, effective in: conference rooms, small offices,
warehouse aisles, and break rooms
 Ultrasonic – detects motion around obstacles, effective in: restrooms, open offices, or any space
where the sensor might not have a direct view of occupants
 Hybrid- combination of both PIR and ultrasonic technologies, lights do not turn on until both
mechanisms detect motion and remains on while either continues to detect motion
Vacancy Sensors utilize the same basic technology as occupancy sensors, but must be turned on
manually. These sensors can be applied to most interior applications for additional energy savings
(please see occupancy sensor template for more detailed instruction).
Timers can be use in addition to occupancy sensors for interior applications to provide incremental
savings in areas where occupancy based control is impractical. Timers can also be effectively applied
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Energy and Water Conservation Design Requirements for SRM Projects
in exterior applications where lighting is not needed all night.
Photocontrols are the most cost effective way to achieve precision in automatic lighting control for
exterior applications.
Daylighting Controls utilize available daylight by turning electric lights down when sufficient daylight is
available and can also contribute to peak energy savings. This method requires use of either a
continuous dimming ballast or a step dimming ballast when used with fluorescent luminaires.
Light sources
Fluorescent lights are the most widely used lighting technology in non-residential buildings because of
their widespread availability, ease of application, and low energy usage without sacrificing colorrendering capabilities. Old fluorescent systems with magnetic ballast and large diameter T12 lamps
(tubes) should be replaced with efficient T8 or T5 lamps with electronic ballasts. These newer
fluorescent systems can also be dimmed, making them the optimum choice for daylight responsive
lighting. Fluorescent lamps contain mercury, which can have environmental repercussions if not
disposed of properly. Each state follows specific rules and regulations regarding the disposal of
fluorescent lamps. At least one retail organization (The Home Depot) has recently started a fluorescent
recycling program for all types of fluorescent lamps. A similar program base-wide should be considered
to make recycling easier and more complete.
Ballasts are the component in all fluorescent and high intensity discharge luminaires that regulate the
frequency and operating voltage. In fluorescent lamps, older magnetic ballasts are inefficient and
should be replaced with electronic ballasts, or dimmable electronic ballasts if used with daylighting
controls. Replacing ballasts with a ballast of a different ballast factor can also be a simple and cost
effective way to lower light levels in over-lit spaces.
LEDs are a lighting technology that is still constantly changing and being improved upon. There are
several applications where LEDs are a very energy efficient and effective lighting solution (e.g. exit
signs). When using LEDs for general illumination, illuminance measurements should be taken as part of
an annual maintenance schedule to ensure sufficient light levels are being reached. The lights should
not need to be changed for 2-5 years (depending on operating hours and temperature), but LEDs do
not have a distinct end-of-life that prompts lamp replacement so it is important to include the
measurements in the typical maintenance procedures to ensure light levels do not drop below the
minimum recommended levels.
Despite the slow degradation of light output, LEDs can last a very long time minimizing costly lighting
maintenance. LED life is largely dependant on operating temperature, making them well suited for
exterior applications where heat management is not as much of an issue. If proper thermal
management is not addressed, however, LEDs might stop producing sufficient light sooner than
expected.
High Intensity Discharge (HID) lamps generally refer to a large group of various technologies.
Currently, metal halide lamps with a pulse start mechanism are the most efficient HID lamp available
that provide the color rendering that has come to be expected from electric lighting. Any high pressure
sodium (HPS) or old probe start metal halide system should be analyzed to determine if a higher
efficiency HID system would be cost effective.
Analyzing the cost of a lighting system
Implementing advance lighting systems varies in cost and complexity. The application options
discussed in this appendix will incrementally reduce lighting energy consumption and have been proven
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Energy and Water Conservation Design Requirements for SRM Projects
to be cost effective for most applications. The following general simple payback calculation illustrated
below can provide a basic indication of the potential cost-effectiveness of a lighting project.
YPayback = Cost of upgrade /(TA* ERate* W/100)
where:
YPayback =
=
TA
ERate =
W
=
length of time (in years) it takes for energy savings to pay for new lighting system
annual length of time affected luminaires are operated
cost of electricity (per kWh)
(Difference in) wattage of affected luminaires
The simple payback calculation for lighting systems is highly dependant on the method of control, hours
of operation, and complicated utility rates. For a more in depth cost analysis be sure to find a more
complete method of analysis that characterizes all of the variables specific to the project (the IEA
lighting templates are a great place to start understanding the affects specific technologies can have on
energy consumption).
References
Boyce PR. 1991. “Security Lighting: What we Know and What we Don’t.” Lighting Magazine:
December.
IESNA 9th Edition Handbook, 200, Illuminating Engineering Society of North America.
International Energy Agency Energy Conservation in Buildings and Community Systems (ECBCS)
Annex 46. In Press. “Retrofitting Lighting Systems to Correct Light Levels.”
International Energy Agency Energy Conservation in Buildings and Community Systems (ECBCS)
Annex 46. In Press. In Press. “Efficient Occupancy Sensor Lighting Control.”
International Energy Agency Energy Conservation in Buildings and Community Systems (ECBCS)
Annex 46. In Press. “Intelligent Lighting Controls: Daylighting.”
International Energy Agency Energy Conservation in Buildings and Community Systems (ECBCS)
Annex 46. In Press. In Press. “Lighting Controls: Exterior Lighting
International Energy Agency Energy Conservation in Buildings and Community Systems (ECBCS)
Annex 46. In Press. In Press. “Replacing Incandescent Lamps with
Compact Fluorescent.”
Lighting Research Center: Online Photosensor Tutorial.
National Lighting Product Information Program “Specifier Reports: Photosensors.” March 1998.
National Lighting Product Information Program “Specifier Reports: Dimming
Electronic Ballasts.” October 1999.
NLPIP: Screwbase Compact Fluorescent Lamp Products. June 1999.
Richman, E. E., A. L. Dittmer, and J. M. Keller. Field Analysis of Occupancy Sensor Operation:
Parameters Affecting Lighting Energy Savings. Prepared by Pacific Northwest National
Laboratory for the U.S. Department of Energy.
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Energy and Water Conservation Design Requirements for SRM Projects
U.S. Lighting Market Characterization, Volume 1: National Lighting Inventory and
Energy Consumption Estimate. Navigant Consulting for U.S. Department of Energy. September 2002.
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