BENEFITS OF L.E.D. (LIGHT EMITTING DIODES)

BENEFITS: NO HEAT, LONGEVITY, REDUCED COST, LOW AMERPAGE DRAW.


There is no comparison between the costs of LED lights vs. traditional incandescent options. With incandescent bulbs, and halogen bulbs the true cost of the bulb is the cost of replacement bulbs and the labor expense and time needed to replace them. These are significant factors, especially where there are a large number of installed bulbs. For yachts, office buildings and skyscrapers, maintenance costs to replace bulbs can be enormous. These issues can all be virtually eliminated with the LED option. 


The key strength of LED lighting is reduced power consumption. When designed properly, an LED circuit will approach 80% efficiency, which means 80% of the electrical energy is converted to light energy. The remaining 20% is lost as heat energy. Compare that with incandescent bulbs which operate at about 20% efficiency (80% of the electrical energy is lost as heat). In real money terms, if a 100 Watt incandescent bulb is used for 1 year, with an electrical cost of 10 cents/kilowatt hour, $88 will be spent on electricity costs. Of the $88 expense, $70 will have been used to heat the room, not light the room. If an 80% efficient LED system had been used, the electricity cost would be $23 per year - there would be a cost savings of $65 on electricity during the year. Realistically the cost savings would be higher as most incandescent and halogen light bulbs blow out within a year and require replacements whereas LED light bulbs can be used easily for a decade without burning out.


LED lamps have many advantages over traditional lighting methods. These include

  • Low energy consumption – retrofit bulbs range from 0.83 to 7.3 Watts 
  • Long service life – LED bulbs can last up to 100,000 hours 
  • Durable – LED bulbs are resistant to thermal and vibrational shocks and turn on instantly from -40C° to 185C°, making them ideal for applications subject to frequent on-off cycling, such as garages and basements, yachts.
  • Directional distribution of light – good for interior task lighting 
  • No infrared or ultraviolet radiation – excellent for outdoor use because UV light attracts bugs 
  • Safety and environmentally conscious – LEDs contain no mercury and remain cool to the touch 
  • Fully dimmable – LEDs do not change their color tint when dimmed unlike incandescent lamps that turn yellow as well as halogens.
  • No frequency interference – no ballast to interfere with radio and television signals 
  • Range of color – LEDs can be manufactured produce all colors of the spectrum without filters, they can also produce white light in a variety of color temperatures 


LEDs are better at placing light in a single direction than incandescent or fluorescent or halogen bulbs. Because of their directional output, they have unique design features that can be exploited by clever designs. LED strip lights can be installed under counters, in hallways, and in staircases; concentrated arrays can be used for room lighting. Waterproof, outdoor fixtures are also available. We consider applications such as gardens, walkways, and decorative fixtures outside garage doors to be the most cost-efficient. 


APPLICATIONS: LED lights are more rugged and damage-resistant than compact fluorescents and incandescent bulbs. LED lights don't flicker. They are very heat sensitive; excessive heat or inappropriate applications dramatically reduce both light output and lifetime. Uses include: 

  • Task and reading lamps 
  • Linear strip lighting (under kitchen cabinets) 
  • Recessed lighting/ceiling cans Porch/outdoor/landscaping lighting 
  • Art lighting
  • Night lights 
  • Stair and walkway lighting
  • Pendants and overhead
  • Retrofit bulbs for lamps 
Definitions and Terms:
TERM DEFINITION UNITS  HOW TO INTERPRET
Color Temperature Color of light KELVIN (K)  Sunlight at sunrise is 1800 Kelvin / 100 watt incandescent light bulb is 2850 KelvinsOvercast sky is 6500 kelvins
Color RenderingINDEX (CRI)  Lights effect on color  Scale of 0 to 100 with sunlight at 100 The higher the number, the more “TRUE” the color will look in that light.
Brightness The intensity of the light  LUMENS The higher the lumens the brighter the light,
Power  Amount of electrical energy consumed WATTS  Lower the watts, the lower the energy consumed
Efficacy The efficiency of the bulb to convert electricity into light LUMENS PER WATT More efficient bulbs provide more light using less energy

ATTRIBUTES
Individual LED’s are considerably more efficient; however, the lamp or fixture design is reduced by the driver and electronics, in addition LED’s do not produce heat like incandescent and halogen bulbs.


LED’s last considerably longer than incandescent and halogen or fluorescents lighting. LED’s don’t typically burn out like traditional lighting, but rather decrease in light output. Their “USEFULL LIFE” is defined by the Alliance for Solid -State Illumination Systems and Technologies (ASSIST) as the time it takes until 70% of initial light output is reached. They are resistant to thermal and vibrational shock and perform well when subjected to frequent on-off cycling.


EASE OF IMPLEMENTATION:No additional tools are required for installation of LED fixtures, or for bulb replacements.


OPERATIONAL COSTS:The cost savings of LED’s can be found in smaller wattage lamps or for applications that take advantage of their longevity, such as difficult to reach places. They are also advantageous for dimmable fixtures, since dimmable fluorescents’ are expensive.


LED FREQUENTLY ASKED QUESTIONS

What is an LED?

LED is the common abbreviation for a light-emitting diode. Each individual LED consists of a semiconductor diode that emits light when a voltage is applied to it. The electronics industry has used LED technology for several decades as indicator lights for various electronic devices. In more recent years, LED technology has progressed to the point where it is viable for general lighting applications.

Where have LED’S been used in the lighting industry?

LEDs are commonly used in aesthetic, effect, or specialty lighting applications, including architectural highlighting. Most traffic lights and exit signs, for example, now use red, green or blue LEDs. Marine, Recreational Vehicle, Commercial and Residential applications.

Have LED’s always been used in general illumination lighting?

No. Early attempts to apply LEDs in general illumination lighting failed because they didn't meet the lumen-per-watt output or color requirements. Technology has advanced to the point where using LEDs for general illumination is now successful. Lighting industry experts are gaining a better understanding of how to capitalize on that technology.

Why have past attempts to create general illumination LED’s failed?

Conventional approaches to developing general illumination LEDs often involved retrofitting existing fixtures to house the new LED technology. Instead of investigating the benefits and challenges of LEDs, many early attempts simply used traditional lighting standards and housings. The problem was that LED technology breaks all traditional rules, and it quickly became apparent that old thinking couldn't be applied to this new technology.


What are the advantages to using LED Lights?

LEDs bring several advantages to the lighting industry, including high efficiency and durability, and, with superior life over other lamp sources; their required maintenance is greatly reduced. This translates into energy savings, maintenance savings and an overall reduction in cost of ownership over the product's lifetime.



Whats the difference between efficiency and efficacy?

 Efficacy is a term normally used in cases where the input and output units differ. In lighting, we are concerned with the amount of light (in lumens) produced by a certain amount of electricity (in watts). On the other hand, efficiency is a term that is typically dimensionless. For example, lighting fixture efficiency is the ratio of the total lumens exiting the fixture to the total lumens initially produced by the light source.


How do you evaluate LED products?

Lumen output is only part of the story and can be misleading. To fully evaluate an LED product one needs to review the overall system efficiency, optical control, thermal management of the LEDs, and know at what point in time the fixture will reach 30 percent lumen depreciation. Products with good optical efficiency and thermal management will be able to deliver more lumens, on average, than traditional HID products.

How are LED’s able to out perform HID?
Super-bright white LEDs have the advantage of minimal lumen depreciation, better optical efficiency and high lumens per watt. LEDs also have a vastly longer life span than traditional lamp sources. The luminaire must be designed to leverage these inherent advantages of LEDs. A Total Systems Approach is needed for an LED product to bring ll these features together.

If an LED fixture has lower initial lumen output than a traditional HID light, how can LED claim to deliver lumens more efficiently than HID?

 When you average delivered lumens over the course of 60,000 hours, you'll see that LED outperforms a 400-watt MH lamp operated in a horizontal position. (60,000 hours is used for this comparison to show three full life cycles of the HID.)The MH's lumen depreciation, as well as optical and ballast losses, quickly reduce output of the HID system. Note that there are three relamps over 60,000 hours.Conversely, LED has significantly better lumen maintenance and a more efficient driver. Also note that the LED fixture typically doesn't need relamping from zero to 60,000 hours.Combine this with Beta's exclusive NanoOptic and LED outperforms MH over the course of the life of the fixture.Result: the LED's average delivered lumens is 74% higher than HID over 60,000 hours.


How does ambient temperature affect LED efficiency?

LED fixtures must be designed with junction temperature thermal management as a key component and use the correct LEDs. These products will then be robust enough to operate in most ambient temperature applications. Unlike fluorescent sources, cold temperatures do not impact the performance of LEDs.


What is junction temperature?

Junction temperature is the temperature at the point where an individual diode connects to its base. Maintaining a low junction temperature increases output and slows LED lumen depreciation. Junction temperature is a key metric for evaluating an LED product's quality and ability to deliver long life.The three things affecting junction temperature are: drive current, thermal path, and ambient temperature. In general, the higher the drive current, the greater the heat generated at the die. Heat must be moved away from the die in order to maintain expected light output, life, and color. The amount of heat that can be removed depends upon the ambient temperature and the design of the thermal path from the die to the surroundings. [Source: DOE]The Department of Energy advises: "Heat management and an awareness of the operating environment are critical considerations to the design and application of LED luminaires for general illumination. Successful products will use superior heat sink designs to dissipate heat, and minimize junction temperature. Keeping the junction temperature as low as possible and within manufacturer specifications is necessary in order to maximize the performance potential of LEDs."

Do I have to replace LED Diodes?

An LED does not burn out like a standard lamp, so individual diodes do not need to be replaced. Instead, the diodes gradually produce lower output levels over a very long period of time. If one LED fails, it does not produce a complete fixture outage.

Why is the life span of an LED measures as lumen depreciation?

The life span of an LED is vastly longer than that of incandescent, fluorescent or HID lamp sources, generally lasting 50,000 hours or longer. Although the LED never really burns out, product life span is measured by lumen depreciation.The Illuminating Engineering Society's (IES) current standard for calculating the life of an LED as the point at which the LED reaches 30 percent lumen depreciation.Remember, a 100,000-hour rating is not equivalent to lamp life rating. LED life is rated where it has reached 30 percent lumen depreciation. At 100,000 hours an LED would still be operating, but at a decreased lumen output.
How long is 100,000 hours?24 hours a day 11.4 years18 hours per day 14.8 years12 hours per day 22.8 years8 hours per day 34.2 years


Disclaimer: The information on the system, product or material presented herein is provided for informational purposes only. The technical descriptions, details, requirements, and limitations expressed do not constitute an endorsement, approval, or acceptance of the subject matter by the NAHB Research Center. There are no warranties, either expressed or implied, regarding the accuracy or completeness of this information. By Lighting Sales Connection, Inc.  Full reproduction, without modification, is permissible.