Compact fluorescent lamp

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A spiral-type compact fluorescent lamp. This style has slightly reduced efficiency compared to tubular fluorescent lamps, due to the excessively thick layer of phosphor on the lower side of the twist. Despite this, it has become one of the most popular types among North American consumers since its introduction in the mid 1990s.^[1]

A compact fluorescent lamp (CFL), also known as a compact fluorescent light bulb (or less commonly as a compact fluorescent tube [CFT]) is a type of fluorescent lamp. Many CFLs are designed to replace an incandescent lamp and can fit in the existing light fixtures formerly used for incandescents.

Compared to general service incandescent lamps giving the same amount of visible light, CFLs use less power and have a longer rated life, but generally have a higher purchase price. In the United States, a CFL can save over 30 USD in electricity costs over the lamp's lifetime compared to an incandescent lamp and save 2000 times its own weight in greenhouse gases.^[2] Like all fluorescent lamps, CFLs contain mercury; this complicates the disposal of fluorescent lamps.

CFLs radiate a different light spectrum from that of incandescent lamps. Improved phosphor formulations have improved the subjective color of the light emitted by CFLs such that the best 'soft white' CFLs available in 2007 are subjectively similar in color to standard incandescent lamps.^[3]

[edit] History

The parent to the modern compact fluorescent lamp (CFL) was invented in the late 1890s by Peter Cooper Hewitt.^[4] The Cooper Hewitt lamps were used for photographic studios and industries.^[4] Edmund Germer, Friedrich Meyer, and Hans Spanner then patented a high pressure vapor lamp in 1927.^[4] George Inman later teamed with General Electric to create a practical fluorescent lamp, sold in 1938 and patented in 1941.^[4] The modern CFL was invented by Ed Hammer, an engineer with General Electric, in response to the 1973 oil crisis. While it met its design goals, it would have cost GE about 25 million USD to build new factories to produce them and the invention was shelved.^[5] The design was eventually leaked out and copied by others.^[5]

[edit] Market

A compact fluorescent lamp used outside an office complex.

Globally introduced in the early 1980s, CFLs have steadily increased in sales volume. The most important technical advance has been the gradual replacement of electromagnetic ballasts with electronic ballasts; this has removed most of the flickering and slow starting traditionally associated with fluorescent lighting. There are two types of CFLs: integrated and non-integrated lamps.

[edit] Integrated CFLs

Integrated lamps combine a tube, an electronic ballast and either an Edison screw or bayonet fitting in a single CFL unit. These lamps allow consumers to easily replace incandescent lamps with CFLs. Integrated CFLs work well in standard incandescent light fixtures. This lowers the cost of CFL use, since they can reuse the existing infrastructure. In addition, incandescent light fixtures are relatively inexpensive.

[edit] Non-integrated CFLs

Non-integrated lamps allow for the replacement of consumable bulbs and the extended use of electrical ballasts in a light fixture. This fluorescent bulb itself does not include a ballast. Since the ballasts are placed in the light fixture they are larger and last longer, vis-a-vis the integrated ones. Non-integrated CFL housings can be both more expensive and sophisticated, providing options such as dimming, less flicker, faster starts, etc.^[6][7]

The ballasts make these light fixtures relatively expensive. They cost anywhere from 85 to 200 USD for each recessed can. If a ballast with dimming capabilities is desired the cost is anywhere from 125 to 300 USD per recessed can. Non-integrated CFLs are more popular for professional users, such as hotels and office buildings. The more advanced capabilities of these sophisticated external ballasts (e.g., faster starts, limited flicker, dimming, longer lifespans, etc.) are starting to appear in integrated CFLs.

Another style of non-integrated fitting is the "two piece", where the initial system includes a base adapter and detachable fluorescent tube module, and subsequently only the tube unit is replaced. The Thorn 2D and some Philips PL versions are examples, but while replacement tubes are generally still available, it is rare to see the complete kit on sale, having been overshadowed by cut-price one-piece units.

[edit] CFL power sources

CFLs are produced for both alternating current (AC) and direct current (DC) input. DC CFLs are popular for use in recreational vehicles and off-the-grid housing. Some families in developing countries are using DC CFLs (with car batteries and small solar panels) and/or wind generators, to replace kerosene lanterns.

CFLs can also be operated with solar powered street lights, using solar panels located on the top or sides of a pole and luminaires that are specially wired to use the lamps.

[edit] Comparison with incandescent lamps

[edit] Lifespan

Modern CFLs typically have a lifespan of between 6,000 and 15,000 hours, whereas incandescent lamps are usually manufactured to have a lifespan of 750 hours or 1,000 hours.^[8][9] Some incandescent bulbs claim long rated lifespans of 20,000 hours ^[10] with reduced light output (approximately 500 versus 800 lumens).^[11] The lifetime of any lamp depends on many factors including operating voltage, manufacturing defects, exposure to voltage spikes, mechanical shock, frequency of cycling on and off and ambient operating temperature, among other factors. The life of a CFL is significantly shorter if it is only turned on for a few minutes at a time: In the case of a 5-minute on/off cycle the lifespan of a CFL can be up to 85% shorter, reducing its lifespan to the level of an incandescent lamp.^[12][13][14] The US Energy Star program says to leave them on at least 15 minutes at a time to mitigate this problem.

CFLs give less light later in their life than they do at the start. The light output depreciation is exponential, with the fastest losses being soon after the lamp was new. By the middle to end of their lives, CFLs can be expected to produce 70-80% of their original light output. ^[15] The response of the human eye to light is logarithmic: Each f-number (or photographic 'f-stop') reduction represents a halving in actual light, but is subjectively quite a small change.^[16] A 20-30% reduction over many thousands of hours represents a change of about half an f-stop, which is barely noticeable in everyday life.^[17]

[edit] Energy efficiency

The chart shows the energy usage for different types of light bulbs operating at different light outputs. Points lower on the graph correspond to lower energy use.

For a given light output, CFLs use between one fifth and one quarter of the power of an equivalent incandescent lamp.^[18] Since lighting accounted for approximately 9% of household electricity usage in the United States in 2001,^[19], widespread use of CFLs could save as much as 7% from household usage.

If incandescent lamps are replaced by CFLs the heat produced by the building's lighting system will be reduced. At times when the building requires both heating and lighting, the building's central heating system will then supply the heat.

In contrast, if the building requires both illumination and cooling, then CFLs will use less electricity themselves and will also reduce the load on the cooling system compared to incandescent lamps. This results in two concurrent savings, and since most air conditioners are also electrically powered, they are directly comparable.

There is a third case where electric lighting is used with natural ventilation and without either heating or cooling. In this case the energy savings due to CFLs are simpler to estimate, as described above.

For more details on this topic, see Luminous efficacy.

In order to compare the actual energy efficiency of CFLs with various other lamp technologies such as incandescent, LED and halogen, factors to compare include total lumens, the usefulness of different frequencies of light, the distribution of light around the lamps and other factors.

[edit] Cost

In addition to saving on energy cost, the average life of a CFL is between 8 and 15 times that of incandescents.^[20] While the purchase price of a CFL is typically 3 to 10 times greater than that of an equivalent incandescent lamp, the extended lifetime (fewer lamps to replace and reduced labor) and lower energy use will compensate for the higher initial cost in many applications.^[21] A US article stated "A household that invested $90 in changing 30 fixtures to CFLs would save $440 to $1,500 over the five-year life of the bulbs, depending on your cost of electricity. Look at your utility bill and imagine a 12% discount to estimate the savings."^[22]

[edit] Cost-Effectiveness in Commercial Buildings

CFLs are extremely cost-effective in commercial buildings. A CFL replacing a 75 W incandescent fixture offers an average yearly savings of $22 considering direct energy saving, reduced HVAC cost, and reduced labor to change lamps. The capital investment of $2 per fixture is typically paid back in about one month. Savings are greater and payback periods shorter in regions with higher than average electric rates and, to a lesser extent, higher than average cooling requirements.^[23]

[edit] Noise

CFLs, much as other fluorescent lights, may emit a high-pitched buzzing sound, where incandescents do not. Such sounds are particularly noticeable in quiet rooms, and can be annoying under these circumstances. Newer compact fluorescent light bulbs are nearly noiseless, but some poorly made CFLs may still emit a buzzing sound.

[edit] Radio Frequency

As with all fluorescent lights, CFLs also generate some higher electrical frequencies which both radiate from the light unit itself, and transfer along the interconnecting electrical wiring. This is not generally considered to be a significant problem, but it can result in electronic interference with some other devices.

[edit] Starting time

Incandescents give light almost immediately upon the application of voltage. CFLs take a perceptible time to achieve full brightness, and can take much longer in very cold temperatures. Certain styles of lamp using a mercury amalgam can take up to three minutes to reach full output. Coupling this with the shorter life of CFLs when turned on and off for short amounts of time may make incandescent bulbs more attractive for applications such as outdoor or motion-activated lighting.

[edit] Cleanup of broken bulbs

Broken CFL bulbs release mercury vapors which are harmful to human and ecological health. The EPA has a page dedicated to clean-up of broken CFL Bulbs.^[24] Although mercury in these bulbs is a health hazard,^[24] special handling upon breakage is currently not printed on the packaging of household CFL bulbs in many countries. It is important to note that the amount of mercury released by one bulb can exceed U.S. federal guidelines for chronic exposure. ^[25][26]

[edit] Comparison with alternative technologies

Solid-state lighting has already filled a few specialist niches such as traffic lights and may have the potential to compete with CFLs in the near future. LED lamps have current efficiencies of 30% with higher levels attainable (recently up to 85 lm/w LEDs are available), and a lifetime of around 50,000 hours. Currently LED lamps do not deliver the intensity of light output for domestic uses at a reasonable cost.^[27][28][29]

General Electric is attempting to develop more efficient incandescent bulbs that can produce the same light output as a 60-watt bulb (~800 lumens) but with half the wattage (30 watt). Their ultimate goal is to manufacture an incandescent bulb that will match the CFL's performance (a 15 watt bulb outputting 60-watt equivalency). ^[30] [1]

[edit] CFL availability

[edit] Standard/Integrated CFLs

The US Environmental Protection Agency (EPA) and the US Department of Energy (DOE) run the Energy Star program, which evaluates the energy efficiency of electrical components, including integrated CFLs. Those CFLs with a recent Energy Star certification start in less than one second and do not flicker. There is ongoing work in improving the 'quality' (color-rendering index) of their light.

• Energy Star List of Compact Fluorescent Light Bulbs is a list of the thousands of Energy Star qualified CFLs.^[31] This list of lamps can be downloaded as an Excel file, which shows Lamp model, lumens, light quality (CRI), Watts, and test dates.
• List of Standard CFLs from Energy Federated Incorporated, most of which have Energy Star certification.

[edit] Dimmable CFLs

As of 2007, dimmable CFLs are an emerging category. The dimming range of CFLs is usually between 20% and 90%^[32]. By way of comparison, incandescent lamps have a 0-100% range. Because of these limitations, Dimmable CFLs are not a 100% replacement for incandescent lights, especially for light fixtures that are dimmed for "mood scenes" such as wall sconces in a dining area. At the extreme lower end of a dimmer switch setting (below the 20% dim limit), the operation of a dimmable CFL is indeterminate -- in some cases it may remain at the approximate 20% level, in other cases it may flicker or the starter circuitry may stop and restart^[33]. Above the 80% dim limit, the bulb will generally glow at 100% brightness. Also, Dimmable CFLs have a higher purchase cost than standard CFLs due to the additional circuitry required for dimming. A further limitation is that multiple dimmable CFLs on the same dimmer switch may not appear to be at the same brightness level. However, to address these limitations, PureSpectrum, Inc. has patented a technology that not only provides full dimming functionality to a CFL, it allows the bulb to start (turn on) at levels below 10%, and to mimic operation side-by-side with incandescent bulbs on the same dimmer^[34].

Those with dimmer switches that would like to save energy over incandescent bulbs but still want full dimming functionality can consider halogen bulbs, which are more efficient than incandescent bulbs^[35]. Philips has created a product line called Halogena Energy Saver, which purports to provide energy savings similar to CFLs but also provides the same dimming functionality as incandescent bulbs^[36].

• List of Reflector CFLs that work well in recessed lights. These lights tend to have a very high temperature environment, which used to shorten lamp lifespan.
• List of Dimmable CFLs from the Environmental Defense Fund - most do not yet have Energy Star certification.

Many CF bulbs are not compatible with standard dimmer switches. However, there are some CF bulbs specifically marked as compatible with a standard electronic dimmer as may already be installed for an incandescent lamp. Some dimmable lamps may have a limited range of dimming and produce audible noise when used with some dimmers.^{[citation needed]} The Noli Control Systems claim that their CFLs work on standard incandescent circuits. On the other hand, Leviton sells a dimmer designed to work specifically with Philip's dimmable CFLs.^[37]

[edit] Colors

A photograph of various lamps illustrates the effect of color temperature differences (left to right): (1) Compact Fluorescent: General Electric, 13 watt, 6500 K (2) Incandescent: Sylvania 60-Watt Extra Soft White (3) Compact Fluorescent: Bright Effects, 15 watts, 2644 K (4) Compact Fluorescent: Sylvania, 14 watts, 3000 K

A blacklight CFL.

Color temperature can be indicated in kelvins or mireds (1 million divided by the color temperature in kelvins).

Color temperature is a quantitative measure. The higher the number in kelvins, the 'cooler', i.e., bluer, the shade. Color names associated with a particular color temperature are not standardized for modern CFLs and other triphosphor lamps like they were for the older-style halophosphate fluorescent lamps. Variations and inconsistencies exist among manufacturers. For example, Sylvania's Daylight CFLs have a color temperature of 3500 K, while most other lamps with a 'daylight' label have color temperatures of at least 5000 K. Some vendors do not include the kelvin value on the package, but this is beginning to change now that the Energy Star Criteria for CFLs is expected to require such labeling in its 4.0 revision.

Some manufacturers now label their CFLs with a 3 digit code to specify the color rendering index (CRI) and color temperature of the lamp. The first digit represents the CRI measured in tens of percent, while the second two digits represent the color temperature measured in hundreds of kelvins. For example, a CFL with a CRI of 83% and a color temperature of 2700 K would be given a code of 827.^[38]

CFLs are also produced, less commonly, in other colors:

• Red, green, orange, blue, and pink, primarily for novelty purposes
• Blue for phototherapy
• Yellow, for outdoor lighting, because it does not attract insects
• Black light (UV light) for special effects

Black light CFLs, those with UVA generating phosphor, are much more efficient than incandescent black light lamps, since the amount of UV light that the filament of the incandescent lamp produces is only a fraction of the generated spectrum.

Being a gas discharge lamp, a CFL will not generate all frequencies of visible light; the actual color rendering index is a design compromise (see below). With less than perfect color rendering, CFLs can be unsatisfactory for inside lighting, but modern, high quality designs are proving acceptable for home use.^{[citation needed]}

Other terms that apply to CFLs:

• Full Spectrum
• High Definition

[edit] Environmental issues

The examples and perspective in this article or section may not represent a worldwide view of the subject. Please improve this article or discuss the issue on the talk page.

[edit] Energy savings

Since Compact Fluorescent uses less power to supply the same amount of light as an incandescent lamp, they decrease energy consumption and the environmental effects of electric power generation. Where electricity is largely produced from burning fossil fuels, the savings reduces emissions of greenhouse gases and other pollutants; in other areas the reduction may help reduce negative impacts from radioactive waste, hydroelectric plants, or other sources.

While CFLs require more energy in manufacturing than incandescent lamps, this is said to be offset by the fact that they last longer and use less energy during their lifespan.^[39][40]

Mercury use of compact fluorescent lamp vs. incandescent lamp if powered by electricity generated completely from coal, though coal accounts for only about half of the power production in the United States.

However there is no standard way to calculate the amount of energy 'embodied' in a device (e.g. Should one include the energy consumption/transport of workers in the factory?), and currently there is little in the way of trustworthy evidence to demonstrate the differences between the manufacturing, delivery, and retailing consumption of energy in the different forms of lighting.

[edit] Mercury emissions

CFLs, like all fluorescent lamps, contain small amounts of mercury^[41][42] and it is a concern for landfills and waste incinerators where the mercury from lamps is released and contributes to air and water pollution. In the USA, lighting manufacturer members of the National Electrical Manufacturers Association (NEMA) have voluntarily capped the amount of mercury used in CFLs:

Under the voluntary commitment, effective 15 April 2007, NEMA members will cap the total mercury content in CFLs of less than 25 watts at 5 milligrams (mg) per unit. The total mercury content of CFLs that use 25 to 40 watts of electricity will be capped at 6 mg per unit.^[43]

A June 2007 article calculated that the overall mercury emission by CFLs is less than the mercury released into the atmosphere by coal-fired power generation for series of equivalent incandescent lamps over the same period.^[44] Of course, not all electricity is coal generated, but the mercury from spent CFLs is not released into air if the bulbs are not broken in transport. Only 3% of CFL bulbs are properly disposed of or recycled.^{[citation needed]} This comparison also only refers to the statistics of a CFL bulb surviving its full rated life. ^[45]

Although they make up only 19% of power generation in Canada,^[46] coal power plants are "the largest uncontrolled industrial source of mercury emissions in Canada".^[47] According to the Environmental Protection Agency (EPA), when coal power is used, less mercury is released when fluorescent lamps are used, even including mercury in the lamps. ^[48] EPA is implementing policies to reduce airborne mercury emissions by coal plants, with an objective of 70% reducition by 2018. ^[49]

The Albany Times Union reported that the annual mercury emissions of a single cement plant amounted to 400 pounds.^[50] That amount roughly corresponds to the mercury content in 4,500 million compact fluorescent lamps.

Some manufacturers such as Philips, GE and Turolight make very low mercury content CFLs.^[51] In 2007, Turolight claimed its new Genesis Fusion line contained only 1mg of mercury, making it the lowest EnergyStar approved bulb in North America.

Safe disposal requires storing the bulbs unbroken until they can be processed. Consumers should seek advice from local authorities. Usually, one can either:

• Return used CFLs to where they were purchased, so the store can recycle them correctly; or
• Take used CFLs to a local recycling facility.

Broken CFLs are an immediate health hazard due to the evaporation of mercury into the atmosphere. The U.S. Environmental Protection Agency recommends that, in the absence of local guideline, fluorescent bulbs be double-bagged in plastic bags before disposal.^[24]

The first step of processing CFLs involves crushing the bulbs in a machine that uses negative pressure ventilation and a mercury-absorbing filter or cold trap to contain mercury vapor. Many municipalities are purchasing such machines. The crushed glass and metal is stored in drums, ready for shipping to recycling factories.

According to the Northwest Compact Fluorescent Lamp Recycling Project, because household users have the option of disposing of these products in the same way they dispose of other solid waste, "a large majority of household CFLs are going to municipal solid waste". They additionally note that an EPA report on mercury emissions from fluorescent tube lamp disposal indicates the percentage of total mercury released from the following disposal options: municipal waste landfill 3.2%, recycling 3%, municipal waste incineration 17.55% and hazardous waste disposal 0.2%.^[52]

[edit] How they work

[edit] Parts

Electronic ballast of a compact fluorescent lamp

There are two main parts in a CFL: the gas-filled tube (also called bulb or burner) and the magnetic or electronic ballast. Electrical energy in the form of an electrical current from the ballast flows through the gas, causing it to emit ultraviolet light. The ultraviolet light then excites a white phosphor coating on the inside of the tube. This coating emits visible light. CFLs that flicker when they start have magnetic ballasts; CFLs with electronic ballasts are now much more common. See Fluorescent lamp.

Electronic ballasts contain a small circuit board with rectifiers, a filter capacitor and usually two switching transistors connected as a high-frequency resonant series DC to AC inverter. The resulting high frequency, around 40 kHz or higher, is applied to the lamp tube. Since the resonant converter tends to stabilize lamp current (and light produced) over a range of input voltages, standard CFLs do not respond well in dimming applications and special lamps are required for dimming service.

[edit] End of life

Both the ballast and the lamp tube are subject to failure from normal use. A detailed description of the failure modes of fluorescent lamps is given in the Fluorescent lamp article. Additionally, the electronic ballast may fail since it has a number of component parts; such failures may be accompanied by discoloration or distortion of the ballast enclosure, odors, or smoke. The lamps are internally protected and are meant to fail safely at the end of their lives. Industry associations are working toward advising consumers of the different failure mode of CFLs compared to incandescent lamps, and to develop lamps with inoffensive failure modes. ^[53]

Spent lamps should be recycled to contain the small amount of mercury in each lamp, in preference to disposal in landfills. At end of life, CFLs should be recycled by specialist firms. In the European Union, CFLs are one of many products subject to the WEEE recycling scheme. The retail price includes an amount to pay for recycling, and manufacturers and importers have an obligation to collect and recycle CFLs.

[edit] Design issues

The primary purposes of CFL design are high electrical efficiency and durability. However, there are some other areas of CFL design and operation that are problematic:

• Quality of light: A phosphor emits light in a narrow frequency range, unlike an incandescent filament, which emits the full spectrum, though not all colors equally, of visible light. A mix of phosphors gives a good approximation of daylight or incandescent light can be reached. However, every extra phosphor added to the coating mix causes a loss of efficiency and increased cost. Good quality consumer CFLs use three or four phosphors to achieve a 'white' light with a Color Rendering Index (CRI) of around 80, where 100 represents the appearance of colors under daylight or a blackbody (depending on the correlated color temperature).

• Size: CFL light output is roughly proportional to phosphor surface area, and high output CFLs are often larger than their incandescent equivalents. This means that the CFL may not fit well in existing light fixtures.

• Electronics: Dimming control can be added to the lamp with support from the driver electronics. Using regular CFLs with a dimmer can shorten bulb life and will void the warranty of certain manufacturers.^[54] According to BC Hydro^[55] and Environmental Defense,^[56] dimmable screw-in fluorescent lamps are now available. Westinghouse claims to have released a dimmer that can dim non-dimmable CFLs.^[57]

• Heat: CFLs get warm in operation, so some CFLs are labelled not to be run base up, since heat will shorten the ballast's lifetime. Some CFLs are unsuitable for use in pendant lamps and especially unsuitable for recessed lighting fixtures. CFLs intended for use in such fixtures are available.^[58]

CFLs will fail prematurely if overheated. Current recommendations for fully enclosed, unventilated light fixtures (such as those recessed into insulated ceilings), are either to use 'reflector CFLs' (R-CFL)^[59][60] or to replace such fixtures with those designed for CFLs.^[59]

• Large deployments of CFLs require specialized electronics with low levels of electronic distortion to avoid disturbing the electricity supply.^[61] This is usually not a problem with home use because of the few lamps deployed per site and because current drain is less than that of the replaced incandescent lamps.

• Time to achieve full brightness: Compact fluorescent lamps may provide as little as 50-80% of their rated light output at initial switch on^[62] and can take up to three minutes to warm up, and color cast may be slightly different immediately after being turned on.^[63] This compares to around 0.1 seconds for incandescent lamps, and microseconds for LED lamps, although LED response speed can vary depending on the LED and the electronics that drive it. (For example, LED stoplights have a 0.01 second response rating.^[64]). In practice, this varies between brands/types. It is more of a problem with older lamps, 'warm (color) tone' lamps and at low ambient temperatures.

• Interference: Electronic devices operated by infrared remote control can interpret the infrared light emitted by CFLs as a signal limiting the use of CFLs near televisions, radios, remote controls, or mobile phones.^[65] Broadband over power lines, shortwave radio, and AM radio receive radio interference from the CFLs.^{[citation needed]}

• Use with timers: Electronic (but not mechanical) timers can interfere with the electronic ballast in CFLs and can shorten their lifespan.^[66]

• Fire hazard: Inferior quality electronic components used in some CFLs can cause excessive heat or fire. In some cases the components are outright underrated for the task.^[67]

• Outdoor use: CFLs that are not designed for outdoor use may perform poorly in cold weather; CFLs are available with cold-weather ballasts, which may be rated to as low as -23°C (-10°F).^{[68][dead link]}Standard compact fluorescents will fail to operate at low temperatures. Light output drops at low temperatures.^[69]

• Differences among manufacturers: There are large differences among quality of light, cost, and turn-on time among different manufacturers, even for lamps that appear identical and have the same color temperature.

• Fluorescent lamps get dimmer over their lifetime,^[70] so what starts out as an adequate luminosity may become inadequate. In one test by the US Department of Energy of 'Energy Star' products in 2003-4, one quarter of tested CFLs no longer met their rated output after 40% of their rated service life.^[71][72]

[edit] Other CFL technologies

Another type of fluorescent lamp is the electrodeless fluorescent, known as a radiofluorescent lamp or fluorescent induction lamp. Unlike virtually all other conventional lamps that have hardwired electrical connections to transfer energy to the lamp core, the electrodeless fluorescent accomplishes this solely by electromagnetic induction. The induction is effected by means of a wire-wound ferrite core that projects upward into the bulb encased in an inverted U-shaped glass cover. The wire is energized with high frequency electricity often 2.65 or 13.6 MHz; this ionizes the mercury vapor, exciting the phosphor and producing light. Induction lamps also have greater efficiencies per watt, higher powers than CFLs and a lifetime currently between 15,000 and 100,000 hours.^[73] By 2007, several manufacturers have already introduced dimmable induction lamps, making their application even more flexible and accommodating.

Currently, this type of light source is struggling with a high cost of production, stability of the products produced in China, establishing an internationally recognized standard and problems with EMC^[74] and RFI. Induction lighting is excluded from Energy Star standard for 2007 by the EPA.

Another variation on existing CFL technologies are bulbs with an external nano-particle coating of titanium dioxide. Titanium dioxide is a photocatalyst, becoming ionized when exposed to UV light produced by the CFL. It is thereby capable of converting oxygen to ozone and water to hydroxyl radicals, which neutralize odors and kill bacteria, viruses, and mold spores.

The Cold Cathode Fluorescent Lamp (CCFL) is one of the newest forms of CFL. CCFLs use electrodes without a filament. The voltage of CCFLs is about 5 times higher than CFLs and the current is about 10 times lower. CCFLs have a diameter of about 3 millimeters. The lifetime of CCFLs is about 50,000 hours. The lumens-per-watt value is about half that of CFLs.

CCFLs were initially used for thin monitors and backlighting, but they are now also manufactured for use as lamps. The efficacy (lumens/watt) is actually lower than that of CFLs. Their advantages are that they are instant-on, like incandescents, they are compatible with timers, photocells and dimmers, and they have a long life of approximately 50,000 hours. CCFLs are a convenient transition technology for those who are not comfortable with the short lag time associated with the initial lighting of CFLs. They are also an effective and efficient replacement for lighting that is turned on and off frequently with little extended use (e.g. a bathroom or closet).

[edit] Efforts to encourage adoption

Due to the potential to reduce electric consumption and hence pollution, various organizations have undertaken measures to encourage the adoption of CFLs and other efficient lighting devices, with efforts ranging from publicity to encourage awareness and make CFLs more widely available to direct measures to provide CFLs to the public. Some electric utilities and local governments have subsidized CFLs or provided them free to customers as a means of reducing electric demand (and thereby delaying additional investments in generation).

More controversially, some governments are considering stronger measures to encourage adoption of CFLs or even entirely displace incandescents; some proposed efforts involve tax measures, while others have gone further by instituting bans on future production of incandescent light bulbs. Ireland has announced it intends in 2009 to be the first country to implement such a ban, but the proposal is yet to be subject to public consultation and EU approval. Norway has abandoned attempts to introduce a ban which it calls 'virtually irreconcilable' with EU market rules. It has opted for voluntary agreements. Elsewhere Australia has announced a plan to phase out the use of incandescent lamps by 2010 while Canada has also committed to phasing out incandescent lamps starting in 2012.

In the United States and Canada, the Energy Star program labels compact fluorescent lamps that meet a set of standards for starting time, life expectancy, color, and consistency of performance. The intent of the program is to reduce consumer concerns due to variable quality of products. ^[75]

[edit] Voluntary measures

In April 2008 British Gas announced it would give away 4 free CFLs to each of their 13 million customers, totalling 52,000,000 bulbs.

The Home Depot gave away 1,000,000 n:vision CFLs on Earth Day 2007.

IKEA in the UK gave 6 free CFLs to staff, and will replace them free when they run out in a 'bulb for life' campaign as part of World Environment Day. IKEA in Sweden has also handed out free CFLs to their customers.

Wal-Mart announced in September 2006 that it was starting a campaign to endorse CFLs. The store aims to sell one CFL to every one of their 100 million customers within the next year.^[76]

In Canada, there is an effort to get every household to change at least one lamp. Project Porchlight is mobilizing volunteers to deliver one free CFL door to door to every household in their own neighbourhoods. More than one million bulbs have been delivered since the first campaign in Ottawa in November, 2005. Project Porchlight is active in the provinces of Alberta, Ontario, Saskatchewan and British Columbia, in the Yukon Territory, and is launching state-wide programs in Vermont and New Jersey in 2008.

In other locations in Canada, local utilities regularly undertake 'energy audits' to customers to suggest ways to reduce consumption (and reducing investment requirements for the utilities); CFLs are often given away or provided at subsidized prices to raise awareness of the potential savings.

The Ontario Power Authority has a voluntary program providing immediate cash rebates via coupons for the purchase of CFLs. The campaign is driven by posters, ads and their web site Every Kilowatt Counts.

The US-based nonprofit Environmental Defense initiated a campaign in June 2006 called Make the Switch to encourage the public to switch from incandescent lamps to compact fluorescent lamps. It asked every household in the US to replace three 60-watt incandescent lamps with CFLs. Environmental Defense claims that if every household were to do this, the change could reduce pollution as much as taking 3.5 million cars off the road. In the Netherlands, Greenpeace is attempting to mobilize people to Change 1 million light bulbs to CFLs.

In February 2007, the 18seconds campaign was launched with leaders from business (Yahoo! and Walmart) and US Government (EPA and DOE) to increase awareness of energy efficient lamps as a way to slow global climate change . The coalition was named 18seconds to reflect the amount of time it takes for one person to change a lamp. To coincide with the launch of this campaign, Yahoo has created a Web site 18seconds.org that will track lamp sales and energy savings nationwide and encourage lamp switching competition among cities and states.^[77]

In South Africa, the main electricity supply company Eskom has launched a program to exchange incandescent lamps for CFLs for free. Its aim is to reduce the electrical demand at peak times. [2]

Recognizing that lower income households are less likely to lay out the significantly greater retail price for compact fluorescent lamps, which can cost 5 to 6 times the cost of an incandescent lamp, the non-profit organization Wattsaver [3] is accepting donations that will be used to give compact fluorescent lamps to these lower income households.

In New Zealand an organisation called Energy Mad^[78] was established in 2004. Energy Mad is promoting CFL adoption with a target of introducing five of their branded ecobulbs^[79] into 55% of New Zealand homes.^[80] They are using various promotions with retailers and discount coupons to attempt to achieve this. By utilizing these vouchers, users give Energy Mad the carbon credits due to the implied replacement of an incandescent lamp with the CFL.^[81]

In Australia a company ^[82] offers residents in selected municipalities free compact fluorescent lamps to replace their incandescent lightbulbs, including free installation. Residents have to sign over to them the carbon credits resulting from energy savings over the expected life of the compact fluorescent lamps.

In October 2007, electro distribution companies in Slovenia will give away 800,000 21W Osram CFL light bulbs (one to every household in Slovenia). Project initiator is Slovenian power plant holding - HSE Group.[4]

[edit] Government efforts to encourage adoption of CFLs

[edit]  Australia

On 20 February 2007, the Federal Government announced that by 2010, incandescent light bulbs would be banned in Australia, making it the first country in the world to announce such a ban.^[83][84] It is estimated that greenhouse gas emissions will be cut by 800,000 tonnes (Australia's current emission total is 564.7 million tonnes), a saving of approximate 0.14%. The Government has not announced any concurrent recycling program for old incandescent lamps.^[85] The South Australian government has published an energy saving calculator in order to help people calculate their individual benefits.

[edit]  Belgium

The Environment Minister Bruno Tobback is intent on banning incandescent light bulbs, and thinks the ban on incandescent light bulbs should be included in the list of measures under the Kyoto Protocol.^[86][87] Former energy Minister Kris Peeters supports this position as well.^[88]

[edit]  Canada

On 2007-04-18, the Ontario government's Minister of Energy Dwight Duncan announced that it was planning to ban the sale of inefficient lighting in 2012 to cut the local energy consumption.^[89][90] The Ontario Power Authority has a voluntary program providing immediate cash rebates via coupons for the purchase of CFLs. The campaign is driven by posters, ads and their web site Every Kilowatt Counts (this program ended on Nov 30, 2007).

Following the announcement, the province of Nova Scotia has also pondered a similar ban.^[91] However, Energy Minister Bill Dooks said he expects it would be 4 or 5 years before a ban is in place.

The territory of Nunavut is planning to ban incandescent lamps in May 2007.^[92]

Hydro-Québec offers mail-in rebates for many Energy Star appliances including the fluorescent lamp. They have a vigorous advertising campaign that includes radio, television and bus shelter billboard advertisements. They are currently offering up to $25 in mail-in rebates for their customers who buy the bulbs.^[93]

A week later, on 2007-04-25, the federal government's Environment Minister John Baird announced plans to ban the sale of incandescent lamps by 2012 all over Canada. According to the minister, Canada will save 3-4 billion CAD over the lifetime of the new bulbs.^[94][95]

[edit]  Ecuador

Since 2002 the Government of Ecuador through the project PROMEC www.promec.gov.ec has made efforts to introduce CFL technology for household use. In February 2007, the project of replace six millions of CFL in donation directly to the population with low incomes with no access to this technology began, and through this effort reduce 439000 tonCO2. It is expected that the distribution will happen before the end of 2008. The project has been designed to fulfill the requirement of the United Nations and qualified as Clean Development Mechanism project. Other initiative in this way is the energy efficiency projects in public buildings.www.meer.gov.ec

[edit]  European Union

The European Union has proposed a ban on incandescent light bulbs, planned to come into effect in the near future, but this will not affect existing incandescent bulbs, only the production of new bulbs.^[96] However, the proposal has yet to be approved by all member states or the European Parliament.

[edit]  Finland

On the 26 September 2007, Swedish People's Party MP Christina Gestrin, has posted a bill through the Eduskunta for banning incandescent light bulbs in Finland by 2011. It is estimated that the ban would save Finland around to 200,000 tonnes on carbon dioxide emissions.^[97]

[edit]  Germany

Germany's Environment Minister Sigmar Gabriel has urged the European Commission to ban inefficient light bulbs in the EU in the fight against global warming. The EU could reduce carbon dioxide emissions by 25 million tonnes a year if energy saving light bulbs such as CFLs were used in both the domestic and services sectors. .^[98]

[edit]  India

In India, Fluorescent lamps have been the de-facto standard for urban home illumination for decades. However, many lower middle class homes do not have the electrical wiring that is compatible with FL devices. Since low income households generally cannot afford to rewire their homes, they were compelled to use inefficient tungsten filament (incandescent) bulbs. In recent years, there has been a drive to popularize and implement CFLs in the country. CFLs are compatible with the incandescent bulb sockets and so can be retrofitted into homes with such sockets.Studies have been undertaken by the independent academics, as well as the Indian Administrative Service and the Indian Institute of Technology that recommend an aggressive implementation of the prescription for Education, Policy support, Standards, Demonstrations and Industry involvement for popularising CFLs.^[99][100]

[edit]  Ireland

On 6 December 2007, Ireland's Environment minister John Gormley, delivered his Carbon Budget in Dáil Éireann. Minister Gormley announced that the country would stop using incandescent bulbs by January 2009, making it the first country to implement such a ban. These changes will result in savings of 700,000 tonnes of carbon dioxide emissions from residential lighting and will result in Irish consumers saving over €185 million a year in electricity costs.^[101] However the proposal has yet to undergo public consultation and receive EU approval under market rules.

[edit]  Netherlands

The Netherlands is moving ahead with plans to ban incandescent light bulbs as well. The Environment minister Jacqueline Cramer wants a ban on incandescent light bulbs by 2011.^[102]

[edit]  New Zealand

In response to the Australian ban, New Zealand is considering similar measures. Climate Change Minister David Parker said, "The Australians are talking about looking at banning ordinary light bulbs in 3 years' time. I think by the time that is implemented in Australia - if it is - we will be doing something very similar."^[103]

[edit]  Pakistan

During Pakistan's 2007 summer season, when energy demand is at its peak, the government of Pakistan repeatedly asked the public to use fluorescent lamps (commonly known as energy savers in Pakistan). There were talks of making fluorescent lamps available on subsidised rates.

The newly elected government headed by Mr. Yousuf Raza Gilani (Prime minister) announced its first 100 days plan, and instructed to arrange 10 million pcs of energy saver bulbs at lowest possible price. Which shall give immediate relief against 2200 MW power deficit causing load sheding throughout the country.

^[104]

[edit]  United Kingdom

In the UK, Dr Matt Prescott of Banthebulb.org first proposed a ban in February 2005 and has since lobbied Parliament to tax, phase out and ban domestic incandescent lamps, a measure that has generated controversy. Recently, the light bulb manufacturer Philips has also set up a web site called aSimpleSwitch.com in support of a ban of high energy incandescent light bulb, but the continued use of high efficiency incandescents and halogens; other commentators oppose any proposed ban.^[105] The Government itself focuses its efforts to improve household energy efficiency through its establishment and funding of the Energy Saving Trust.

The Co-op have also stopped selling incandescent lamps in 50 pilot stores, with a view to withdrawing them completely in the future. They have also reduced the prices of their CFLs to make them more attractive in the short term.^[106]

On the 27 September 2007, the government announced plans to phase out the sale of incandescent light bulbs by 2011. Retailers will not replace 150 watt bulbs from January 2008, 100 watt bulbs from January 2009, 40 watt bulbs in 2010, and all remaining high power bulbs by 2011. These plans are voluntary, however they have wide support from retailers such as Currys, Habitat, Woolworths, Co-op, Asda, Morrisons, Sainsbury's and Tesco. This initiative has been criticised by environmental groups such as Greenpeace, and other political parties, who think mandatory measures should be introduced.

Current building regulations also require some of the light fittings in new houses to be specially designed to only take CFLs. These fittings have a 2 or 4-pin socket, instead of the usual bayonet or screw fitting.

[edit]  United States of America

In January 2007, California State Assembly member Lloyd E. Levine (D-Van Nuys) announced that he would introduce the 'How Many Legislators does it take to Change a Light Bulb Act' (a reference to light bulb jokes), which would ban the sale of incandescent light bulbs in California starting in 2012.^[107] That bill is now dead, though a competing bill by California State Assembly member Jared Huffman (D-Santa Rosa) was signed by Governor Schwarzenegger on 12 October.^[108]

A few days later, Connecticut state Representative Mary M. Mushinsky (D-Wallingford) proposed a similar ban for the state of Connecticut.^[109][110]

On 8 February 2007, New Jersey Assemblyman Larry Chatzidakis introduced a bill that calls for the state to switch to fluorescent lighting in government buildings over the next three years. "The light bulb was invented a long time ago and a lot of things have changed since then," said Chatzidakis. "I obviously respect the memory of Thomas Edison, but what we're looking at here is using less energy."^[111]

On 1 October 2007, West Virginia Governor Joe Manchin named 1 October 'Change a Light, Change the World Day', while giving a speech at West Virginia University. The university on the same day launched a massive program called WECAN, or West Virginia University Conservation Awareness Now. On launch day, there was a light bulb exchange in conjunction with Osram Sylvania at the university student union giving a compact fluorescent bulb for each regular incandescent bulb turned in.^[112]

On 19 December 2007, United States President George W. Bush signed the Energy Independence and Security Act of 2007. Among other provisions, that law sets efficiency standards for electric lights that will see the incandescent light bulb phased off the US market beginning in 2012.^[113]

[edit] See also

• Luminous efficacy
• Energy efficiency
• Banning of incandescent lightbulbs

[edit] Notes and references

[edit] External links

Wikimedia Commons has media related to:

Compact fluorescent lamp

• US government Energy Star's page on fluorescent bulbs
• LampRecycle.org - for information on recycling spent mercury-containing lamps
• Typical Lumen Outputs and Energy Costs for Outdoor Lighting
• Spectra of Fluorescent Light Bulbs
• www.smartfuelchoices.com - Information on energy saving alternatives
• Snopes Urban Legends Archive, regarding mercury exposure from a broken CFL
• New Light Bulbs in Plain English 3 minute explanatory video
• Light Bulbs from Great Lakes Green Initiative. Differentiates various types of bulbs; considers mercury and recycling issues.
• Email sent to European Parliamentarians: About the negative health effects of low energy light bulbs / CFLs
• Aircycle.com - A company specializing in the recycling of environmentally hazardous CFLs

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