Energy Efficient Lighting

From: www.eartheasy.com
http://www.eartheasy.com/live_energyeff_lighting.htm

Electric lighting burns up to 25% of the average home energy budget.

The electricity used over the lifetime of a single incandescent bulb costs 5 to 10 times the original purchase price of the bulb itself.

Compact Fluorescent Lights (CFL) and Light Emitting Diode (LED) bulbs have revolutionized energy-efficient lighting.

CFLs are simply miniature versions of full-sized fluorescents. They screw into standard lamp sockets, and give off light that looks just like the common incandescent bulbs - not like the fluorescent lighting we associate with factories and schools.

LEDs are small, solid light bulbs which are extremely energy-efficient. New LED bulbs are grouped in clusters with diffuser lenses which have broadened the applications for LED use in the home.

LED Lighting

LEDs (Light Emitting Diodes) are solid light bulbs which are extremely energy-efficient. Until recently, LEDs were limited to single-bulb use in applications such as instrument panels, electronics, pen lights and, more recently, strings of indoor and outdoor Christmas lights.
Manufacturers have expanded the application of LEDs by "clustering" the small bulbs. The first clustered bulbs bulbs were used for battery powered items such as flashlights and headlamps. Today, LED bulbs are made using as many as 180 bulbs per cluster, and encased in diffuser lenses which spread the light in wider beams. Now available with standard bases which fit common household light fixtures, LEDs are the next generation in home lighting.

The high cost of producing LEDs has been a roadblock to widespread use. However, researchers at Purdue University have recently developed a process for using inexpensive silicon wafers to replace the expensive sapphire-based technology. This promises to bring LEDs into competitive pricing with CFLs and incandescents. LEDs may soon become the standard for most lighting needs. We are following these developments with interest and will report the latest updates in this research.

Benefits of LED lightbulbs

Long-lasting - LED bulbs last up to 10 times as long as compact fluorescents, and far longer than typical incandescents.

Durable - since LEDs do not have a filament, they are not damaged under circumstances when a regular incandescent bulb would be broken. Because they are solid, LED bulbs hold up well to jarring and bumping.

Cool - these bulbs do not cause heat build-up; LEDs produce 3.4 btu's/hour, compared to 85 for incandescent bulbs. This also cuts down on air conditioning costs in the home.

Mercury-free - no mercury is used in the manufacturing of LEDs.

More efficient - LED light bulbs use only 2-10 watts of electricity (1/3rd to 1/30th of Incandescent or CFL) Small LED flashlight bulbs will extend battery life 10 to 15 times longer than with incandescent bulbs. Also, because these bulbs last for years, energy is saved in maintenance and replacement costs. For example, many cities in the US are replacing their incandescent traffic lights with LED arrays because the electricity costs can be reduced by 80% or more.

Cost-effective - although LEDs are expensive, the cost is recouped over time and in battery savings. For the AC bulbs and large cluster arrays, the best value comes from commercial use where maintenance and replacement costs are expensive.

Light for remote areas - because of the low power requirement for LEDs, using solar panels becomes more practical and less expensive than running an electric line or using a generator for lighting.

Choosing an LED lightbulb
Many different models and styles of LED bulbs are emerging in today's marketplace. When choosing a bulb, keep in mind the following:

• Estimate desired wattage - read the package to choose desired illumination level. For example, a 3W LED is equivalent in output to a 45 W incandescent.
• Choose between warm and cool light - new LED bulbs are available in 'cool' white light, which is ideal for task lighting, and 'warm' light commonly used for accent or small area lighting.
• Standard base or pin base - LEDs are available in several types of 'pin' sockets or the standard "screw' (Edison) bases for recessed or track lighting.
• Choose between standard and dimmable bulbs - some LED bulbs, such as the LumiSelect series, are now available as dimmable bulbs.

The common styles of LED bulbs include the following:

Diffused bulbs
In this style LED bulb, clusters of LEDs are covered by a dimpled lens which spreads the light out over a wider area. Available in standard Edison bases, these bulbs have many uses, such as area lighting for rooms, porches, reading lamps, accent lamps, hallways and low-light applications where lights remain on for extended periods. more info

Diffused high power bulbs
Designed for standard household use, these bulbs produce light equivalent to a 100-watt incandescent bulb. The EvoLux (pictured), and ZetaLux (pictured above) are the first UL Listed and FCC approved LED light bulbs for general household illumination. more info

Track Lighting
Available in pin base or standard (Edison) base, LEDs are ideal for track lighting. LEDs do not contribute to heat buildup in a room because no matter how long they remain on, they do not get hot to the touch. Also, because they are 90% more efficient than incandescents, and last 10 times longer than CFLs, the frequency of changing bulbs is greatly reduced. more info

Recessed Downlight and Spotlight bulbs
LEDs are now available for standard recessed lighting pots and housings. The light output and color quality are similar to incandescent downlights, but draws only about one-fifth of the power. Also, because they are 90% more efficient than incandescents. and last 10 times longer than CFLs, the frequency of changing bulbs is greatly reduced. more info

Spotlight and Floodlight LEDs
The spotlight LED lacks a dispersing lens, so it appears brighter as its light is directed forward. It runs cool and will last over 50,000 hours due to advanced thermal management design. The floodlight model gives a spread-out dispersed light. Well suited for ceiling lights, outdoor floodlights. retail display lighting, landscape lighting and motion sensors. more info


LED Terminology

CRI - Coloring Rendering Index. CRI represents the quality of light and its faithfulness to render colors correctly. The EvoLux bulb, for example, features a CRI of 75 for Cool White and 80 for Warm White making it one of the highest in the industry.
CCT - Correlated Color Temperature is the measure used to describe the relative color appearance of a white light source. CCT indicates whether a light source appears more yellow/gold/orange or more blue, in terms of the range of available shades of "white." CCT is given in kelvins (unit of absolute temperature).
RGB - stands for red, green, and blue, the three primary colors of light. When the primaries are mixed, the resulting light appears white to the human eye. Mixing the light from red, green, and blue LEDs is one way to produce white light. The other approach is known as phosphor conversion [see below].
Luminous Flux - the flow of light measured in lumens. With light bulbs, it provides an estimate of the apparent amount of light the bulb will produce.


LED Colors

Red - red is the traditional color for maintaining night vision.
Green - green is now the preferred color for pilots and the military. The green color is also great for retaining night vision, and it doesn’t erase the red markings on maps and charts.
Blue - many people like the blue because it is very easy on the eyes. Blue appears to be a good reading light for elderly eyes. Elderly folks report that they can read under the blue light for hours without eyestrain, compared to severe eyestrain in less than 30 minutes with incandescent lighting.
White - the most popular of the LED colors. It produces a soft white light, without harsh reflection, glare or shadows.
Amber - LED amber bulbs do not attract flying insects, as do ordinary white bulbs. Amber LEDs are used outdoors in areas such as patios and decks where insects flying around lights are a nuisance.

CFL Lighting: Benefits

Efficient: CFLs are four times more efficient and last up to 10 times longer than incandescents. A 22 watt CFL has about the same light output as a 100 watt incandescent. CFLs use 50 - 80% less energy than incandescents.

Less Expensive: Although initially more expensive, you save money in the long run because CFLs use 1/3 the electricity and last up to 10 times as long as incandescents. A single 18 watt CFL used in place of a 75 watt incandescent will save about 570 kWh over its lifetime. At 8 cents per kWh, that equates to a $45 savings.

Reduces Air and Water Pollution: Replacing a single incandescent bulb with a CFL will keep a half-ton of CO2 out of the atmosphere over the life of the bulb. If everyone in the U.S. used energy-efficient lighting, we could retire 90 average size power plants. Saving electricity reduces CO2 emissions, sulfur oxide and high-level nuclear waste.

High-Quality Light: Newer CFLs give a warm, inviting light instead of the "cool white" light of older fluorescents. They use rare earth phosphors for excellent color and warmth. New electronically ballasted CFLs don't flicker or hum.

Versatile: CFLs can be applied nearly anywhere that incandescent lights are used. Energy-efficient CFLs can be used in recessed fixtures, table lamps, track lighting, ceiling fixtures and porchlights. 3-way CFLs are also now available for lamps with 3-way settings. Dimmable CFLs are also available for lights using a dimmer switch.

Choosing a CFL

CFLs come in many shapes and sizes. When purchasing CFLs, consult the seller for recommendations and consider the following:
• Choose your preferred light quality
CFL bulbs have a Kelvin or 'K' number listed on the packaging. CFLs with K numbers between 2700-3000 give off a soft bright light like incandescents. CFLs with K numbers between 3500-6000 give off a bright light. As you go up the K number scale the light gets bluish and closer to daylight.

For example:
Approx. 2700K = Warm White (looks just like incandescent)
Approx. 5000K = Cool White (white/blue, bright light)


• Choose the shape. CFLs are available in a variety of shapes to fit a range of lamps and lighting fixtures. See below on this page for the most popular CFL shapes.
• Match lumens to the incandescent being replaced. Lumens indicate the amount of light being generated. (Watts is a measure of energy use, not light strength.) To compare lumens and watts see chart below:

CFL Models

CFLs are available in a variety of styles or shapes. Some have two, four, or six tubes. Older models, and specialty models, have separate tubes and ballasts. Some CFLs have the tubes and ballast permanently connected. This allows you to change the tubes without changing the ballast. Others have circular or spiral-shaped tubes. In general, the size or total surface area of the tube determines how much light the bulb produces.

The following CFL bulb models come with standard sockets for easy installation in most common household applications. These bulbs are available in our online store.

Spiral Lamps
These bulbs are designed as a continuous tube in a spiral shape which has similar outside shape and light casting qualities to a standard incandescent bulb. Spiral CFL bulbs are made in several sizes to fit most common fixtures. more info

Triple Tube Lamps
These CFLs have more tubing in a smaller area, which generates even more light in a shorter bulb. They pack high light output into a very small space and can be used in fixtures designed for incandescent bulbs, such as table lamps, reading lamps, open hanging lamps, and bare bulb applications. more info

Standard Lamps
These are spiral lamps with a dome cover. They are designed to give the appearance of the traditional light bulb for consumers looking for the more familiar light bulb appearance. The glass diffuser provides a quality of light similar to the 'soft-white' type of incandescent bulbs. more info

Globe Lamps
This shape is commonly used in bathroom vanity mirrors or open hanging lamps, and bare bulb applications. Bathroom vanities usually require multiple bulbs, which generate radiant heat. The CFL globe will reduce this heat buildup while saving energy. The glass diffuser provides a soft-white light. more info

Flood Lamps
These lamps are designed to be ideal for recessed and track lighting fixtures, indoors and outdoors. They provide diffused, soft, white light, and generate less heat than will an incandescent flood or a halogen bulb. more info

Candelabra
The screw-in torpedo-shape and the small-base of this bulb is designed for smaller light fixtures throughout the house, from chandeliers to sconces. To use a smaller candelabra-based bulb in a regular socket, you can use a socket reducer. more info

Limitations of CFL lightbulbs

Although CFLs are an excellent source of energy-efficient lighting, they are not always the best choice for all lighting applications. Here are a few limitations to consider:

On/Off cycling: CFLs are sensitive to frequent on/off cycling. Their rated lifetimes of 10,000 hours are reduced in applications where the light is switched on and off very often. Closets and other places where lights are needed for brief illumination should use incandescent or LED bulbs.

Dimmers: Dimmable CFLs are available for lights using a dimmer switch, but check the package; not all CFLs can be used on dimmer switches. Using a regular CFL with a dimmer can shorten the bulb life span.

Timers: Most CFLs can be used with a timer, however some timers have parts which are incompatible with CFLs; to check your timer, consult the timer package or manufacturer. Using an incompatible timer can shorten the life of a CFL bulb.

Outdoors: CFLs can be used outdoors, but should be covered or shaded from the elements. Low temperatures may reduce light levels - check the package label to see if the bulb is suited for outdoor use.

Retail lighting: CFLs are not spot lights. Retail store display lighting usually requires narrow focus beams for stronger spot lighting. CFLs are better for area lighting.

Mercury content: CFLs contain small amounts of mercury which is a toxic metal. This metal may be released if the bulb is broken, or during disposal. New 'Alto' CFL bulbs are now available with low-mercury content. These low-mercury CFLs are available at our online store. For more information about mercury and CFLs, see below.

The principle reason for reduced lifespan of CFLs is heat. CFLs exhibit shorter lifespans in light fixtures and sockets where there is low air-flow and heat build-up such as recessed lighting. For these types of sockets it is recommended to ues specially designed CFLs for recessed lighting or LEDs. Another main reason for reduced lifespan of CFLs is too-frequent on/off cycling. These bulbs should be used where they will be left on for steady periods without being flicked on and off.

Mercury and CFLs

Mercury is a toxic metal associated with contamination of water, fish, and food supplies, and can lead to adverse health affects. A CFL bulb generally contains an average of 5 mg of mercury (about one-fifth of that found in the average watch battery, and less than 1/100th of the mercury found in an amalgam dental filling). A power plant will emit 10mg of mercury to produce the electricity to run an incandescent bulb compared to only 2.4mg of mercury to run a CFL for the same time. The net benefit of using the more energy efficient lamp is positive, and this is especially true if the mercury in the fluorescent lamp is kept out of the waste stream when the lamp expires.

All fluorescent lamps do not contain the same amount of mercury. Philips lamps with Alto Lamp Technology, for instance, contain less mercury than conventional fluorescent lamps. Philips claims the bulbs have the lowest amount of mercury of any bulb on the market at less than 3.8 mg per bulb. To achieve this, Philips uses a specially developed mercury capsule which ensures the exact amount of mercury is placed in a tiny glass capsule which is attached to the lamp cathode.

Handling and Disposal of CFLs

The mercury in compact fluorescent bulbs poses no threat while in the bulb, but if you break one:
- open a window and leave the room for 15 minutes or more
- use a wet rag to clean it up and put all of the pieces, and the rag, into a plastic bag
- place all materials in a second sealed plastic bag
- call your local recycling center to see if they accept this material, otherwise put it in your local trash. Wash your hands afterward.

Burned out CFLs can be dropped off at Home Depot and Ikea stores. Another solution is to save spent CFLs for a community household hazardous waste collection, which would then send the bulbs to facilities capable of treating, recovering or recycling them. For more information on CFL disposal or recycling, you can contact your local municipality.