Wednesday, August 31, 2011

Changing an exterior light bulb at 1,768 feet-MUST SEE VIDEO!!!

Think your job is tough? Stressful? Today we lighten things up a little, with a neat video showing a man scalling an exterior tower to change the light bulb at the very top of it.

Be careful, your hands may get sweaty just watching this!

http://www.youtube.com/watch?v=hFMHjDqHL_Y

Tuesday, August 30, 2011

Definitions of IESNA Luminaire Classification System (LCS) and BUG Ratings



The Illuminating Engineering Society of North America (IESNA) defines the light distribution and optical control of roadway and area lighting luminaires by the number of zonal lumens expressed as a percentage of the total lamp lumens. These classifications allow designers to choose the proper product to control spill light, light trespass, and sky glow. The LCS replaces the older IESNA Cutoff Classification System.

The BUG Rating system categorizes luminaires according to the amount of Backlight, Uplight and Glare that they have, and is calculated based on the number of lumens in the various LCS secondary zones. A luminaire's BUG Rating may be used to evaluate its optical performance related to light trespass,sky glow, and high-angle brightness control.

There are three major zones that designers need to reference when creating an outdoor lighting design. These three zones are the Front Lighting Zone, Back Lighting Zone and Upper Lighting Zone. These three areas are further divided into secondary zones to allow the designer to control unwanted light while selecting luminaires with the proper distribution to put light where it is needed. These zones are described below:


•FL (Forward Low) – This zone ranges from nadir (0) to 30 degrees vertical and counter-clockwise from 270 to 90 degrees horizontal (in front of the luminaire). The light emitted in this zone reaches from directly below the luminaire to 0.6 mounting heights from the luminaire.

•FM (Forward Medium) – This zone ranges from 30 to 60 degrees vertical and counter-clockwise from 270 to 90 degrees horizontal (in front of the luminaire). The light emitted in this zone reaches from 0.6 to 1.7 mounting heights from the luminaire.

•FH (Forward High) – This zone ranges from 60 to 80 degrees vertical and counter-clockwise from 270 to 90 degrees horizontal (in front of the luminaire). The FH can contribute to light trespass. However, it can be used to illuminate larger areas. The light emitted in this zone reaches from 1.7 to 5.7 mounting heights from the luminaire.

•FVH (Forward Very High) – This zone ranges from 80 to 90 degrees vertical and counter-clockwise from 270 to 90 degrees horizontal (in front of the luminaire). The light emitted in this zone reaches beyond 5.7 mounting heights from the luminaire. The FVH can contribute to light trespass if near the site perimeter. This is also the angle range most responsible for glare.

•BL (Back Low) – This zone ranges from nadir (0) to 30 degrees vertical and counter-clockwise from 90 to 270 degrees horizontal (behind the luminaire). The light emitted in this zone reaches from directly below the luminaire to 0.6 mounting heights from the luminaire.

•BM (Back Medium) – This zone ranges from 30 to 60 degrees vertical and counter-clockwise from 90 to 270 degrees horizontal (behind the luminaire). The light emitted in this zone reaches from 0.6 to 1.7 mounting heights from the luminaire.

•BH (Back High) – This zone ranges from 60 to 80 degrees vertical and counter-clockwise from 90 to 270 degrees horizontal (behind the luminaire). The BH can contribute to light trespass especially from perimeter fixtures. However it can be used to illuminate larger areas. The light emitted in this zone reaches from 1.7 to 5.7 mounting heights from the luminaire.

•BVH (Back Very High) – This zone ranges from 80 to 90 degrees vertical and counter-clockwise from 90 to 270 degrees horizontal (behind the luminaire). The light emitted in this zone reaches beyond 5.7 mounting heights from the luminaire. The BVH can contribute to light trespass, especially from perimeter fixtures. This is also the angle range most responsible for glare.

•UL (Up Low) – This zone ranges from 90 to 100 degrees vertical and 360 degrees around the luminaire. The UL is responsible for contributing the most to sky glow, especially as observed from great distances.

•UH(Up High) – This is the highest uplight value and ranges from 100 to 180 degrees vertical and 360 degrees around the luminaire. Light emitted more directly upward affects sky glow directly above a city.


Backlight, Uplight, Glare (BUG) Rating System
The Backlight, Uplight, and Glare ratings may be used to evaluate luminaire optical performance related to light trespass, sky glow, and high-angle brightness control. These ratings are based on zonal lumen calculations for the LCS secondary solid angles. Each rating, B, U & G, has six ranges, numbered 0 - 5. The lowest rating value, 0, is the strictest, and a rating of 5 essentially means no restrictions. For example, a Backlight rating of B0 is very restrictive, while B5 means no restrictions on the backlight emitted from the luminaire. B2-U0-G1 would be an example of a complete luminaire BUG Rating.

Monday, August 29, 2011

OLED's- defined & explained.


OLEDs are evolving as complementary sources for indoor lighting, says Verbatim’s JEANINE CHROBAK-KANDO, who provides an overview of technology, desirable characteristics and the current status of today’s OLED lighting products.
+++++
This article was published in the June 2011 issue of LEDs Magazine. Here are excerpts from the article:

Organic light-emitting diodes (OLEDs) now appear in a host of commercial electronics applications, most commonly in mobile phones, MP3 players, radio display panels in high-end cars, tablet PCs, and other consumer gadgets. An understanding of OLED technology has been with us for over half a century since researchers at Nancy-Université, France, first observed electroluminescence in organic materials in the 1950s. The affect was only apparent when relatively high voltages were applied to the materials.

The technology currently employed is attributed to W. Tan and A. VanSlyke, and was invented while these researchers were working at Kodak. The breakthrough was to produce a technology that operated at a low voltage and was relatively economical to manufacture. Today’s OLED construction is based upon a Kodak patent, and in November of 1997 Touhoku-Pioneer started the first mass-production of OLEDs, initially for car dashboard displays.
The first OLED screens in personal digital assistants (PDAs) appeared in 2004. By 2008 consumer electronics companies were demonstrating large-screen televisions with high resolution, high contrast ratio and peak luminance of 600 cd/m2.

The drivers of OLED development in these display applications have been the need to reduce cost, weight and power consumption and to provide a better user experience through improved contrast and viewing angle. But what about OLEDs as general light sources?

How OLEDs work
OLEDs work by sandwiching a layer of organic material between two electrodes, an anode and a cathode, and depositing the whole thing onto a substrate, typically glass or plastic. When a low DC voltage is applied to the electrodes (positive to the anode, negative to the cathode), light is emitted when electrically-charged particles (holes and electrons) combine within the organic film. The characteristics and intensity of light emitted, and how it is extracted from the OLED assembly, determine its suitability for lighting applications.

OLEDs need a large emission surface to be suitable for lighting applications so that they emit sufficient light to be useful. The quality of light, usually expressed as its color rendering index (CRI), is important in rendering colors accurately. Low-power operation, meaning high efficiency in converting electricity to light, is vital in a world focused on reducing energy consumption and CO₂ emissions. Also, in common with the requirements of OLED displays, OLED lights should not contain hazardous substances, need to be simple to operate, and must exhibit fast on/off response.



The CRI of a light source is determined by shining the light onto eight different-colored tiles, numbered R1 to R8, and analyzing the spectrum of the light reflected from the tiles. In general, CRI is quoted as the Ra value, which is the average figure across all of the test colors (R1-R8). R9, the color red, is not used in the calculation of Ra, but is important within the spectrum of human vision, so a high R9 figure is also desirable in OLED lighting. The wavelength of light above R9 (approximately 650nm) contributes little to human vision. Today’s OLED panels exhibit an R9 value of 84 and an Ra of greater than 80.

What’s available today? The latest dimmable, color-tunable and white-tone-tunable OLED panels are available in sizes up to about 140 x 140 mm. They offer luminance of approximately 1000 cd/m2 at a color temperature of 3000K, enhanced by a light-extraction film on the luminous surface. Power consumption is about 2W. Panels are typically between 3.6 mm and 8.65 mm thick and have an operating life of over 8000 hours before the output falls to 70% of its initial value.

The white tone is tunable from 2700K – a typical warm-white figure – to about 6500K, equivalent to bright sunlight. Using a simple 3-channel electronic controller located on the back of each panel, the color can be tuned virtually instantaneously. Using this feature, together with dimming, the emotional impact of a lighting scheme based on OLED panels can be changed to reflect the mood required for the environment. For example, bright, white light may be desirable in the morning but more subdued, relaxing lighting with muted colors may be preferable towards the end of the day.

The technical protocols for RGB color tuning (DMX) and dimming (DALI) are well established, and low-cost controllers are widely available. Panels are easily calibrated and matched using the controllers to compensate for differences between panels cased by manufacturing process variations. In the near future, there is an expectation that the DALI protocol will be extended to include all aspects of color control, as well as dimming functions.

OLEDs are not yet ready to replace general indoor lighting, as has been suggested by some enthusiasts. However, they are now at the stage where they complement ambient lighting and task lighting to produce beautifully-balanced lighting schemes both in places of work and in the home. Their potential in retail environments and other public spaces is unlimited, and their low power requirements meet the demands of the most ardent environmentalists.

Friday, August 26, 2011

Formulas for determining Group Relamping and Spot Relamping Costs


There are a variety of reasons to practice group relamping, in which a set of lamps is replaced at a scheduled time, rather than spot relamping, in which lamps are only replaced when they burn out. Most of these reasons apply to fluorescent and high-intensity discharge (HID) lamps rather than incandescents, which have much shorter lifetimes.
• Group relamping requires much less labor per lamp than spot relamping. A worker might take as long as a half hour to retrieve and install a single lamp. If all the materials were on hand for a large number of lamps, a worker could move systematically from fixture to fixture and cut the required time to about 3 minutes per lamp. The process would also be less disruptive, because group relamping is usually done outside working hours.
• Group relamping is easy to schedule and delegate to outside contractors, who have special equipment and training.
• Group relamping provides brighter and more uniform lighting because lamps are replaced before their output has fully depreciated. Direct energy benefits result if the designer, anticipating group relamping, uses a smaller safety factor.
• Group relamping offers increased control over the replacement lamps, reducing the chances of mixing incompatible lamps—such as those with different color temperatures.

Group Relamping Cost
Annualized Cost ($) = A x (B + C)
A = Operating Hours/Year ÷ Operating Hours Between Relampings

B = (Percentage of Lamps Failing Before Group Relamping x Number of Lamps) x (Lamp Cost + Labor Cost to Spot Replace 1 Lamp)
C = (Lamp Cost, Group Relamping + Labor Cost to Group Relamp 1 Lamp) x Number of Lamps



Spot Relamping Cost

Average Annual Cost ($) = (Operating Hours/Year ÷ Rated Lamp Life) x (Lamp Cost + Labor Cost to Replace 1 Lamp) x Total Number of Lamps

GROUP vs. SPOT ANALYSIS

T8 lensed troffers
Group relamping has higher lamp costs but much lower labor costs, in this case providing a 31 percent overall savings. Group relamping also provides additional benefits in lighting quality and easier facility management.
Relamp cycle (hours) Average relamps per year Average material cost per year Average labor cost per year Total average cost per year
Spot relamping on burnouta 20,000 525 $1,391 $3,150 $4,541
Group relamping at 70% of rated life)b 14,000 750 $1,988 $1,125 $3,133
——————— —————— ——————— —————
Difference 225 $597 -$2,025 -$1,428
(31% savings)

Notes:
a. Assumes labor costs of $6.00/lamp for relamping and cleaning, material cost of $2.65/lamp, and 3,500 hours/y operation.
b. Assumes labor costs of $1.50/lamp for relamping and cleaning, same material costs and operating hours as for spot relamping.
Source: U.S. Environmental Protection Agency

Wednesday, August 24, 2011

Determining Target Light Levels

The Illuminating Engineering Society of North America has developed a procedure for determining the appropriate average light level for a particular space. This procedure (used extensively by designers and engineers) recommends a target light level by considering the following:

•the task(s) being performed (contrast, size, etc.)
•the ages of the occupants
•the importance of speed and accuracy

Then, the appropriate type and quantity of lamps and light fixtures may be selected based on the following:

•fixture efficiency
•lamp lumen output
•the reflectance of surrounding surfaces
•the effects of light losses from lamp lumen depreciation and dirt accumulation
•room size and shape
•availability of natural light (daylight)

When designing a new or upgraded lighting system, one must be careful to avoid overlighting a space. In the past, spaces were designed for as much as 200 footcandles in places where 50 footcandles may not only be adequate, but superior. This was partly due to the misconception that the more light in a space, the higher the quality. Not only does overlighting waste energy, but it can also reduce lighting quality.

Within a listed range of illuminance, three factors dictate the proper level: age of the occupant(s), speed and accuracy requirements, and background contrast.

For example, to light a space that uses computers, the overhead light fixtures should provide up to 30 fc of ambient lighting. The task lights should provide the additional footcandles needed to achieve a total illuminance of up to 50 fc for reading and writing. For illuminance recommendations for specific visual tasks, refer to the IES Lighting Handbook, or to the IES Recommended Practice No. 24 (for VDT lighting).

Tuesday, August 23, 2011

Load Shedding Ballasts- explained.

A building’s demand for electric power is the sum of the power required to run its electrical equipment in operation at any given time. Demand rises and falls as equipment is turned on and off. Peak demand is the highest level of demand over a given period. It’s the most expensive power the utility must produce, and these high costs are passed along to customers. Demand charges can represent 25% of a commercial building’s electric energy costs.

To encourage its customers to reduce demand during peak demand periods, utilities, independent system operators (ISOs), and other power providers are offering demand-response programs that provide financial incentives to building owners who agree to curtail load on request—either at scheduled times or during an emergency.

Building owners can significantly reduce their electric utility costs, therefore, if they can curtail load on a schedule, in response to price signals, or on demand by a utility—a strategy called load shedding. When it comes to lighting, this means switching or dimming. To address this need, the major manufacturers have begun introducing load-shedding ballast products.

Load-shedding ballasts:

* Provide a way to reduce input power upon an external demand
* Can be instant-start or program-start
* Can be bi-level switching, bi-level dimming or continuous dimming

Dimming is preferable to switching in occupied spaces in which users perform stationary or critical tasks—i.e., where changes in light output should be unnoticeable to a high degree.


How low can light levels go before occupants object? In developing a prototype for load-shedding ballast technology subsequently commercialized by lamp and ballast maker OSRAM SYLVANIA, the Lighting Research Center studied the question and concluded that they could dim the lamps by as much as 40% for brief periods without upsetting 70% of the building’s occupants or hindering their productivity. LRC studies also showed that nine out of 10 occupants accepted the reduction when they were told that it was being done to reduce peak demand.

Solutions are generally classified as low voltage (respond to a control signal from low-voltage wiring) or line voltage (respond to a control signal from line-voltage wiring). Low-voltage solutions enable integration of the ballast with other control strategies such as daylighting control and scheduling. Line-voltage solutions are well suited for retrofit because no low-voltage wiring needs be installed, just a signal transmitter.

Monday, August 22, 2011

CASE STUDY: LED modules bring new light to Boise Idaho YMCA aquatic center

(as reported in LEDs Magazine)



The YMCA in Boise, Idaho is open 20 hours a day. And up until several weeks ago, a midnight swim had begun to look like just that. Lighting levels had deteriorated. The metal-halide fixtures, designed to reflect light off a white ceiling, had burned out in several cases. Chlorine from the water had caused the ceiling to turn brown.

“Really, almost from day one the lighting solution was not what we had hoped for. But fifteen years into operation, the lifeguards couldn’t see as well as they needed to and it was heading toward a safety issue,” described Jim Everett, CEO of the Treasure Valley Family YMCA. Everett had other issues as well: maintenance on the lighting fixtures tended to be difficult because of the high ceiling and having to work around the pools.
Finally, an elaborate truss system held the existing 66 lighting fixtures and tearing it out was cost-prohibitive. “If we had to replace all those fixtures it would not have been cost effective,” said Everett.

After weighing several options, including blanket replacement of the metal-halide luminaires and several different LED vendors, the YMCA decided to work with a provider of task-specific LED lighting, SimplyLEDs (Garden City, ID), and LED array provider Bridgelux (San Jose, CA). Together, they provided a drop-in replacement for each of the 66 fixtures, keeping the still functional and attractive truss system intact.

LED replacement modules
The replacement kit for each fixture consists of 4 Piazza Series LED modules and two power supplies, which consume 150W. This kit compares to two 400W metal-halide bulbs with ballasts, which consumed approximately 920W each. Energy savings is 770W per fixture or 80 percent.

One of the YMCA’s main requirements was a rapid ROI. “We wanted something that was socially responsible with a reasonable return-on-investment,” said Everett. “By retrofitting the existing fixtures with an LED solution, we saved a considerable amount of money,” said Bob Deely, President and CEO of SimplyLEDs. Each fixture had a changeover time of approximately 20 minutes to remove the metal-halide light engine and ballasts and install the LED modules and reflector.
The design team chose aluminum reflectors to direct the LED light to the pool level. They experimented with various reflector shapes, finally settling on a gull-wing type design for optimal lighting effect.

A further design criterion involved adapting the LEDs to the caustic pool environment. High humidity and chlorine levels dictated that the LED modules be hermetically sealed. “We leveraged a technology from a company that makes LED marker lights for aircraft, AeroLEDs [Nampa, ID], described Deely. The LEDs are sealed in a water- and air-tight module. Epoxy adheres the polycarbonate lens to the LEDs and to the heat sink. The only wires (to the LEDs) exiting the heat sink are wrapped in heat-shrink tubing. The wires go through a silicon rubber grommet lined in silicone paste. The power supply is IP67 rated. Both the modules and power supply have a 5-year warranty.

The light output per fixture is now approximately 13,500 lm at 150W or 90 lm/W efficacy. Although the total lumen output is lower than with the metal-halide bulbs, SimplyLEDs was able to increase light output levels on the pool by 50 percent by taking advantage of the beam angle of the LEDs and the custom-designed reflector (see photo). A CCT of 5000K, very close to that of daylight (5500K), was chosen.

Beyond the savings in energy cost of approximately $20,000/yr, the removal of the metal-halide lamps also eliminated the fire hazard associated with these lights. In addition, whenever there was a power outage, the YMCA had to wait approximately 30 minutes until the metal-halide lamps cooled and could be restarted. This inconvenience no longer exists. Moreover, because the maintenance cost of the LEDs is nearly zero, Everett estimated a maintenance savings of $5000 per year.

Other advantages to the LED installation include increased lighting uniformity in the pool area and reduced glare off the water. “The quality of the light is really fantastic. I play a lot of water polo, and I really notice how much better I can see in the pool now,” said Everett.

Everett said the strong drivers for adopting LEDs were really the terrific energy savings, fast installation and reasonable ROI. “Also, we don’t have much tolerance for interruptions, since we’re open twenty hours a day, seven days a week. The willingness to work after hours and work quickly made a big difference on this project. We needed people who understood our business model and could work within our constraints,” he said.

Friday, August 19, 2011

Dark Skies Lighting Initative

Dark Skies is about protecting our night skies from light pollution. There are numerous associated initiatives to educate, promote regulation and implementation of efficient and effective lighting systems worldwide.

What is light pollution? It is the brightening of the night sky that inhibits the observation of stars and planets, caused by street lights and other man-made sources.

The International Dark-Skies Association (IDA) has introduced regulations to limit light pollution. The purpose of the regulation is to:

•Permit reasonable uses of outdoor lighting for nighttime safety, utility, security, and enjoyment while preserving the ambiance of the night;
•Curtail and reverse any degradation of the nighttime visual environment and the night sky;
•Minimize glare and obtrusive light by limiting outdoor lighting that is misdirected, excessive, or unnecessary;
•Conserve energy and resources to the greatest extent possible;
•Help protect the natural environment from the damaging effects of night lighting.
All outdoor lighting fixtures (luminaires) shall be installed in conformance with this Regulation and with the provisions of the Building Code, the Electrical Code, and the Sign Code, as applicable and under permit and inspection, if such is required.

Lighting that is exempt from this regulation:


1.Lighting in swimming pools and other water features governed by Article 680 of the National Electrical Code.
2.Exit signs and other illumination required by building codes.
3.Lighting for stairs and ramps, as required by the building code.
4.Signs are regulated by the sign code, but all sign lighting is recommended to be fully shielded.
5.Holiday and temporary lighting (less than thirty days use in any one year).
6.Football, baseball, and softball field lighting; only with permit from the authority recognizing that steps have been taken to minimize glare and light trespass, and utilize sensible curfews.
7.Low voltage landscape lighting, but such lighting should be shielded in such a way as to eliminate glare and light trespass.


For more information, http://www.darksky.org/

United States Department of Energy CALiPER Program- Summaries of testing LEDs

As we explained in an earlier blog, the Department of Energy is evaluating the progress of LED (light emitting diode) as they are poised to one day replace standard incandescent as well as other main-stream lighting technologies.

Here are links to a summary for each round of the CALiPER testing...

PILOT ROUND SUMMARY REPORT

http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/cptp_pilot_testing_results_summary_draft_12-06-06.pdf

ROUND 1 SUMMARY REPORT- Report includes test results and analysis for products tested in Round 1, including downlights, desk/task lamps, and undercabinet, outdoor area, and surface mount lighting

http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/cptp_round_1_testing_results_summary.pdf

ROUND 2 SUMMARY REPORT-Report includes test results and analysis for products tested in Round 2, including R30 and A-lamp replacement lamps, downlights, desk/task lamps, outdoor wall lighting, and refrigerated display lighting

http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/cptp_round_2_summary_final_draft_8-15-2007.pdf

ROUND 3 SUMMARY REPORT-Report includes test results and analysis for products tested in Round 3, including directional and A-lamp replacement lamps, downlights, task lamps, and outdoor fixtures

http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/caliper_round_3_summary_fnl.pdf

ROUND 4 SUMMARY REPORT-Report includes test results and analysis for products tested in Round 4, including T8, MR16, and candelabra replacement lamps, downlights, desk/task lamps, and undercabinet and outdoor lighting

http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/caliper_round4_summary_final.pdf

Round 5 Summary Report
Report includes test results and analysis for products tested in Round 5, including linear, A-lamp, and MR16 replacement lamps, downlights, desk/task lamps, undercabinet lighting, and outdoor lighting

http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/caliper_round_5_summary_final.pdf

Round 6 Summary Report
Report includes test results and analysis for products tested in Round 6, including small replacement lamps (MR16, A-lamps, and candelabra lamps), desk lamps, a downlight, a recessed wall fixture, and two different types of outdoor lighting products. (23 pages, September 2008

http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/caliper_round_6_summary_final.pdf

Round 7 Summary Report
Report includes test results and analysis for products tested in Round 7, including outdoor area and streetlights, downlights, and replacement lamps. (28 pages, January 2009)

http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/caliper_round_7_summary_final.pdf

Round 8 Summary Report
Report includes test results and analysis for products tested in Round 8, including replacement lamps, downlights and track lights, undercabinet fixtures, and outdoor fixtures. (28 pages, July 2009)

http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/caliper_round_8_summary_final.pdf

Round 9 Summary Report
Report includes test results and analysis for products tested in Round 9, including recessed downlights, linear replacement lamps, smaller replacement lamps, and a desk lamp. (33 pages, October 2009)

http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/caliper_round-9_summary.pdf

Round 10 Summary Report
Report includes test results and analysis for products tested in Round 10, including parking structure luminaires, outdoor wallpack luminaires, cove lighting luminaires, and replacement lamps. (36 pages, May 2010)

http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/caliper_round-10_summary.pdf

Round 11 Summary Report
Report includes test results and analysis for products tested in Round 11, including roadway arm-mount and post-top luminaires, linear replacement lamps, high-bay luminaires, and small replacement lamps. (40 pages, October 2010)

http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/caliper_round-11_summary.pdf

Round 12 Summary Report
Report includes test results and analysis for products tested in Round 12, including recessed downlights, track lights, A-lamps, SSL replacements for linear fluorescent lamps, and cove lights.

http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/caliper_round-11_summary.pdf

Wednesday, August 17, 2011

Spectrally Enhanced Lighting

The U.S. Department of Energy (DOE) conducts studies on spectrally enhanced lighting (SEL) as part of its lighting activities. Here you'll learn about spectrally enhanced lighting and find information about studies and implementation.

SEL is a simple strategy that uses existing products and technology to significantly reduce energy use from lighting in commercial buildings. This low-risk, high-return strategy can provide energy savings of more than 20-40% at no additional cost, according to results of the DOE study, Spectrally Enhanced Lighting Program Implementation for Energy Savings, Field Evaluation (August 2006)

Recent findings show that the color of lighting can affect the energy efficiency of lighting systems. When the spectral properties of ambient lighting are shifted to be more like the color of daylight (more white), our eyes respond the same as if lighting levels were increased — the pupils of our eyes get smaller, spaces seem brighter, and we see things more clearly.

The concept behind SEL is that a significant amount of energy can be saved by using lamps that have less light output, but higher correlated color temperature (CCT). Lamps with higher CCT appear brighter than those with lower CCT, so the actual light output of higher CCT lamps can be decreased, while maintaining equivalent perceived brightness and visual acuity. Unlike other energy efficiency strategies, SEL is not a technology — it's a different way to quantify light that can be used with any type of lighting design to improve energy performance. Energy savings are achieved by using high performance and high CCT lamps coupled with lower ballast factor, extra efficient electronic ballasts. SEL is a market-ready, cost effective solution for quick energy savings.

Tuesday, August 16, 2011

Daylight Harvesting---defined.

The Illuminating Engineering Society (IES) summarizes Daylighting harvesting as the process that takes advantage of available daylight to augment electric lighting systems. Dimming ballasts and photoreceptors can reduce electric lighting loads proportional to the amount of daylight that enters the space. The more usable daylight entering the space, the more the electric lights can be dimmed, resulting in significant energy savings—as much as 60 percent of the connected lighting load to the space.



Another definition, provided by Wikipedia, defines daylight harvesting as; "Daylight Harvesting is the term used in sustainable architecture and the building controls and active daylighting industries for a control system that reduces the use of artificial lighting with electric lamps in building interiors when natural daylight is available, in order to reduce energy.

Monday, August 15, 2011

Daylighting....defined.

What is daylighting?

Daylighting is the use of indirect natural lighting to illuminate the interior of buildings, reducing the need for electric lighting.

According to a presentation given by Larry Schoff with the United States Department of Energy Energy Efficiency & Renewable Energy Department, the benefits that daylighting offers are as follows:



•Offers a plesant and appealing environment
•A natural interior environment with excellent color rendering
•Proven improved academic performance
•Significant energy and demand savings
•The luminous efficacy of direct beam sunshine is about 113 lumens per watt, and a clear northern sky is 30% better.
•Unlike electric lighting, in the case of daylighting the "watts" don't make the meter turn any faster.
•Daylighting not only supplies lumens for free, but also results in a lower cooling load.
•Good daylighting designs lower A/C demand and allow for specifying smaller coolers
Schoff also points out that dimming is a necessary part of a good daylighting system.

To view his complete presentation, follow this link:

http://www.michigan.gov/documents/F_Lansing__Daylighting_94544_7.pdf

Friday, August 12, 2011

BALLAST FACTOR- defined.

One of the most important ballast parameters for the lighting designer/engineer is the ballast factor. The ballast factor is needed to determine the light output for a particular lamp-ballast system.


Ballast factor is a measure of the actual lumen output for a specific lamp-ballast system relative to the rated lumen output measured with a reference ballast under ANSI test conditions (open air at 25 °C [77 °F]). An ANSI ballast for standard 40-watt F40T12 lamps requires a ballast factor of 0.95; the same ballast has a ballast factor of 0.87 for 34-watt energy saving F40T12 lamps. However, many ballasts are available with either high (conforming to the ANSI specifications) or low ballast factors (70 to 75%). It is important to note that the ballast factor value is not simply a characteristic of the ballast, but of the lamp-ballast system. Ballasts that can operate more than one type of lamp (e.g., the 40-watt F40 ballast can operate either 40-watt F40T12, 34-watt F40T12, or 40-watt F40T10 lamps) will generally have a different ballast factor for each combination (e.g., 95%, <95%, and >95%, respectively).

Ballast factor is not a measure of energy efficiency. Although a lower ballast factor reduces lamp lumen output, it also consumes proportionally less input power. As such, careful selection of a lamp-ballast system with a specific ballast factor allows designers to better minimize energy use by "tuning" the lighting levels in the space. For example, in new construction, high ballast factors are generally best, since fewer luminaires will be required to meet the light level requirements. In retrofit applications or in areas with less critical visual tasks, such as aisles and hallways, lower ballast factor ballasts may be more appropriate.

To avoid a drastic reduction in lamp life low ballast factor ballasts (<70%) should operate lamps in rapid start mode only. This is particularly relevant for 32-watt F32T8 lamps operated at high frequency.

Finding the ballast factor for lamp-ballast combinations may not be easy, as few ballast manufacturers provide this information in their catalogs. However, if the input power for a particular lamp-ballast system is known (usually found in catalogs) an estimate of the ballast factor is possible.

Wednesday, August 10, 2011

Introducing....INDUCTION lighting

Induction lighting is one of the best kept secrets in energy-efficient lighting. Simply stated, induction lighting is essentially a fluorescent light without electrodes or filaments, the items that frequently cause other bulbs to burn out quickly. Thus, many induction lighting units have an extremely long life of up to 100,000 hours. To put this in perspective, an induction lighting system lasting 100,000 hours will last more than 11 years in continuous 24/7 operation, and 25 years if operated 10 hours a day.


In contrast with all other electrical lamps that use electrical connections through the lamp envelope to transfer power to the lamp, in electrodeless lamps the power needed to generate light is transferred from the outside of the lamp envelope by means of (electro)magnetic fields. There are two advantages of eliminating electrodes. The first is extended bulb life, because the electrodes are usually the limiting factor in bulb life. The second benefit is the ability to use light-generating substances that would react with metal electrodes in normal lamps.

Induction technology is far from new. Nikola Tesla demonstrated induction lighting in the late 1890s around the same time that his rival, Thomas Edison, was working to improve the incandescent light bulb. In the early 1990s, several major lighting manufacturers introduced induction lighting into the marketplace.

Applications with High Potential for Induction Lighting•Hard-to-reach locations that make maintenance costs high, such as street lighting and tunnels, or in high ceilings where there is continuous operation, such as hotel rotundas
•Cold environments, such as supermarket walk-in coolers and freezers
•Where high-quality lighting is required or highly desirable
•Where high lumen output is required
•In areas that require lamps to reach full illumination immediately.

Tuesday, August 9, 2011

Are incandescent light bulbs being BANNED in the United States???

No.

According to Acuity Brands Lighting, a major light fixture manufacturer based outside of Atlanta, GA, "The regulation is not a product "ban", but a performance requirement for wattage, lumen output and life.

The regulation being referred to is from EISA (Energy Independence and Security Act 2007).
A general service incandescent lamp (light bulb) is defined as a standard incandescent or halogen type lamp that:

• Is intended for general service applications,
• Has a medium screw bases,
• Has a lumen range of 310-2600 (40 - 100W in today’s wattages), and
• Is capable of operating at least partially in the range of 110-130 volts.

So, in essence the standard 40,60,75 and 100 watt "A" lamp that most homeowners use will either become more efficient, or an alternative will be necessary, most likely CFL (Compact FLuorescent) or LED (light emitting diode). A listing of the light bulbs that will be affected, along with their approved incandescent replacement, can be found here:

http://www.acuitybrands.com/CustomerResources/Sustainability/Product_Regulations/General_Service_Incandescent.aspx

Another great resource can be found here:

http://www.nemasavesenergy.org/assets/_cxFki8alkGc9XKG6n78cA.pdf

The EISA legislation does have some exempted lamps-

Rough service, vibration service, 3-way lamps, 150 watt and shatter resistant.

The United States Department of Energy is authorized to monitor sales of these exempted lamps between 2010 and 2025 and impose regulations if appropriate.

Monday, August 8, 2011

LED testing report LM-80 EXPLAINED

LM80 sets the standards for uniform test methods for LED manufacturers under controlled conditions for measuring LED lumen maintenance while controlling the LED's case temperature. It also requires the LED manufacturer to measure at a 55 degree celsius, 85 degree celsius as well as one other case temperature chosen by the manufacturer, typically 110 degrees celsius. It also requires the lumen maintenance for at least 6,000 hours of constant DC mode operation. The preferred method is 10,000 hours. LED manufacturers then extrapolate this data to provide lumen maintenance out to L70 or useful lumens life.

At this time IESNA is working on TM21 that will standardize this extrapolation method for all LED manufacturers.

Friday, August 5, 2011

Ever seen a $10 Million Light Bulb before??????

After 18 months of product testing, Philips Lighting North America has won the $10 million L-Prize, the federal government’s contest seeking an efficient replacement for the common 60W light bulb.

Sponsored by the U.S. Department of Energy, the L Prize is the first government-sponsored technology competition designed to spur lighting manufacturers to develop high-quality, high-efficiency solid-state lighting products to replace the common light bulb.

The US Department of Energy said yesterday that if every 60-watt incandescent light bulb in the country was replaced with the L-Prize winner, the nation would save $3.9 billion each year in energy costs.

The 35 terawatt-hours of electricity that would be saved would also avoid 20 million metric tons of carbon emissions being pumped into the atmosphere.

The Philips L-Prize Lamp uses LED technology to provide the equivalent light to a 60W bulb using only 10 watts.

Philips submitted 2,000 of its bulbs for consideration by the L-Prize in late 2009.


Testing included examination of lighting performance, stress tests and testing in the field at various locations, including a supermarket in Sacramento, California, and a McDonalds restaurant in Jackson, Wisconsin, as well as a theatre in Skokie, Illinois, and a hospital in Orlando, Florida, among others.

As well as winning the $10 million prize, as the first L-Prize winner Philips will receive the support of 31 utilities and energy efficiency program partners who have pledged to promote the winning light bulb to more than 100 million consumers.

The L-Prize Lamp looks set to hit stores in early 2012.


“The L Prize challenges the best and brightest minds in the U.S. lighting industry to make the technological leaps forward that can greatly reduce the money we spend to light our homes and businesses each year,” said Energy Secretary Steven Chu.

http://photos.prnewswire.com/medias/switch.do?prefix=/appnb&page=/getStoryRemapDetails.do&prnid=20110803%252fCL46572&action=details

Wednesday, August 3, 2011

United States Department of Energy CALiPER Program

The DOE's Solid State Lighting Commercially Available LED Product Evaluation and Reporting (CALiPER) program independently tests and provides unbiased information on the performance of commercially available SSL products.

The test results guide DOE planning for ENERGY STAR® and technology procurement activities, provide objective product performance information to the public, and inform the development and refinement of standards and test procedures for SSL products.

DOE supports testing of a wide, representative array of SSL products available for general illumination, using industry-approved test procedures. Guidelines for product selection ensure that the overall set of tests provides insight on a range of lighting applications and product categories, a range of performance characteristics, a mix of manufacturers, a variety of LED devices, and variations in geometric configurations that may affect testing and performance.

Commercially available products are purchased and then tested by one of several prequalified lighting testing laboratories arranged to assist this program. All luminaires are tested with both spectroradiometry (in an integrating sphere) and goniophotometry, along with temperature measurements (taken at the hottest accessible spots on the luminaire)
and off-state power consumption.

Manufacturers of tested products are given an opportunity to comment on test results prior to their finalization. Testing results, summaries, and interpretations are distributed in hard copy and via the DOE SSL website.

To learn more, here is a link to FAQ's http://www1.eere.energy.gov/buildings/ssl/caliper_faq.html

Here is a link to the CALiPER testing results
http://www1.eere.energy.gov/buildings/ssl/reports.html

Monday, August 1, 2011

Average Rated Life: High Pressure Sodium (H.I.D.)

Unlike the change in average rated life of metal halide based on different burn positions, High Pressure Sodium, another High Intensity Discharge lamp, has the same rated life regardless of burn position.

Typically, High Pressure Sodium lamps, regardless of wattage, are rated at 24,000 hours or more. The HPS lamps that deviate from this are specialty HPS lamps, such as color improved HPS lamps, non-cycling and horticulture lamps.

According to Philips 2011 Lighting Catalog, Improved color rendering HPS lamps have an average rated life of 15,000 hours. Their non-cycling HPS lamps are rated at 30,000 hours and the Horticulture lamps at 15-16,000 average rated hours.

The general lighting HPS lamps, typically with a 24,000 average rated life, gain this mortality rating from a large representation of lamps in laboratory tests under controlled conditions at 10 or more operating hours per start. It is based on a survival of 67% of the lamps, and allows for indivdual lamps or groups of lamps to vary considerably from the average.

In comparison, Metal Halide lamps are given their average rated life under the same test conditions, but with a survival rate of 50% of the lamps tested.