1
1.1
INTRODUCTION
ORGANIZATION
JOONIX ENERGY PVT LTD. started its photovoltaic operations in 1992. The company conceptualiz conceptualizes, es, manufacture manufacturess and designs designs Solar Photovoltaic Photovoltaic Systems, Systems, Solar Lanterns, Solar Solar Home Home Lighti Lighting ng Syste Systems, ms, Solar Solar Street Street Lighti Lighting ng Syste Systems, ms, LED Street Street Lighti Lighting ng Systems Systems and other systems systems for miscellaneous miscellaneous applications. applications. The company company has highly highly qualified, experienced and competent directors in this field. The company manufactures SPV SPV syst system emss whose whose clie client ntele ele incl includ udes es vario various us Gove Govern rnme ment nt Nodal Nodal Agenc Agencie iess and Government Departments. The Company designs and manufactures Solar Photovoltaic systems specially tailored to the customer’ customer’ss needs needs and demands. demands. Joonix Joonix Energy Energy Pvt Ltd is an ISO ISO 9001 certifie certified d organization dedicated to the highest levels of quality. The products of the company are evaluated evaluated at Solar Energy Center (Ministry (Ministry of New and Renewable Energy, Govt. of India). Joonix Energy Pvt Ltd is a full-service company offering unique solar PV products and complete complete energy solutions, solutions, from initial Consultati Consultation on to Project Project concievement, concievement, Project Development Development and Design, Design, Manufacturi Manufacturing, ng, Installat Installation ion and Maintenance. Maintenance. We strive strive hard to create products that provide solar energy at the lowest possible cost in the industry. These products are uniquely designed to install onto existing building infrastructures, without without penetrations penetrations and other major modificati modifications. ons. The Company manufacture manufacturess SPV
1
syst system emss and and suppl supplie iess the the same same to vari variou ouss Gove Govern rnme ment nt Nodal Nodal Agenc Agencie ies, s, Priv Privat atee Organization & Individuals.
1.1. 1.1.1 1
Quali uality ty Phil Philos osop ophy hy
At Joonix Energy Pvt ltd, our commitment to total quality extends to all layers of the organization organization,, empowering empowering every individual individual - from engineering, engineering, to manufacturi manufacturing, ng, to service and support - to anticipate and meet our customers' requirements. The result of this customer-driven quality philosophy is the relentless pursuit of innovation, not for its own sake, but for the continual improvement of our products and processes, and for the satisfaction and ultimate competitive advantage of our customers.
1.1.2 1.1.2
Appr Approv ovals als and and cert certifi ificat cation ionss
1)
ISO 9001 – 2000
2)
TCL TCL (TRA (TRANS NSPA PAC CAFIC AFIC CERT CERTIF IFIC ICAT ATIO IONS NS LTD) TD)
3)
NABC NABCB B ( NATI NATION ONAL AL ACCR ACCRED EDIA IATI TION ON BOAR BOARD D FOR BODI BODIES ES))
1.1.1
Products
➢
SOLAR HOME LIGHTING SYSTEM
Home lighting Systems Systems are powered powered by solar energy using solar solar cells that convert solar energy (sunlight) directly to electricity. The electricity is stored in batteries and used for the purpose of lighting whenever required. These systems are useful in non-electrified 2
rural areas and as reliable emergency lighting system for important domestic, commercial and industrial applications. The SPV systems have found important application in the dairy industry for lighting milk collection/ chilling centres mostly located in rural areas. The Solar Home Lighting system is a fixed installation designed for domestic application. The system comprises of Solar Solar PV Module (Solar (Solar Cells), Cells), charge controller controller,, battery battery and lighting system (lamps & fans).
➢
SOLAR LANTERN
A Solar lantern is a simple application of solar photovoltaic technology, which has found good acceptance in rural regions where the power supply is irregular and scarce. Even in the urban areas people prefer prefer a solar lantern as an alternative alternative during power cuts because of its simple mechanism. A solar Lantern is made of three main components - the solar PV panel, the storage battery and the lamp. The operation is very simple. The solar energy is converted to electrical energy by the SPV panel and stored in a sealed maintenance-free battery for later use during the night hours. A single charge can operate the lamp for about 4-5 hours.
➢
SOLAR STREET LIGHT
This system is designed for outdoor application in un-electrified remote rural areas. This system is an ideal application for campus and village street lighting. The system is provided with battery storage backup sufficient to operate the light for 10-11 hours daily.
3
The system is provided with automatic ON/OFF time switch for dusk to down operation and overcharge / deep discharge prevention cut-off with LED indicators. The solar street light system comprise of
•
74 Wp Solar PV Module
•
12 V, 75 Ah Tubular plate battery with battery box
•
Charge Controller cum inverter (20-35 kHz)
•
11 Watt CFL Lamp with fixtures
•
4 metre mild steel lamp post above ground level with weather proof paint and
mounting hardware. •
The SPV modules are reported to have a service life of 15-20 years. Tubular
Batteries provided with the solar street lighting system require lower maintenance; have longer life and give better performance as compared to pasted plate batteries used earlier. The systems systems electronic provide for over-charge and over-discha over-discharge rge cut-off cut-off essential essential for preventing battery and luminaries damages.
➢
LED STREET LIGHT
An LED street light (also called LED road lighting) is an integrated LED (Light Emitting Diode) light fixture that is used as street lighting. Because they are more energy efficient than other technologies used for street lighting, LED street lights can save on the cost of keeping streets well lit during the night.
4
An LED street light is an integrated light that uses LEDs as its light source. These are considered integrated lights because the luminaries and the fixture are not separate parts. In manufacturing, the LED light cluster is sealed on a panel and then assembled to the LED panel with a heat sink to become an integrated lighting fixture. A light-emitting-diode lamp is a solid-state lamp that uses light-emitting diodes (LEDs) as the source source of light. Since the light output of individual individual light-emitt light-emitting ing diodes is small compar compared ed to incande incandesce scent nt and compact compact fluore fluoresce scent nt lamps, lamps, multip multiple le diodes diodes are used used together. LED lamps can be made interchangeable with other types. Most LED lamps must also include internal circuits to operate from standard AC voltage. LED lamps offer long life and high efficiency, but initial costs are higher than that of fluorescent lamps.
➢
Solar Photovoltaic industry in India
Begu Begun n as far far back back as in the the mid mid 70’s 70’s sola solarr phot photov ovol olta taic ic prog progra ramm mmee of the the Government of India is one of the largest in the World. While the rest of the world has prog progre ress ssed ed trem tremen endou dousl sly y in prod product uctio ion n of basi basicc sili silico con n monoc monocry ryst stal alli line ne photolytic cells, in India the major players are Central Electronics Ltd, BHEL, REIL and the other manufacturers of SPV modules are in fact assemblers sourcing the cells and carrying out assembly. Where this segment of basic manufacturing has not shown much growth in India and is unlikely also in the near future due to high costs involved in manufacturing monocrystalline silicon cells from scratch, the market is growing for SPV applications based products with the active encouragement of the government.
5
Electricity and social development go hand in hand. Rural areas of India are so farflung that in some cases it is decided not to lay down conventional electricity lines due to the small populace to be served and high cost of laying lines. Conventional gensets are also not feasible due to recurring maintenance problems. The best solution under the circumstances is solar photovoltaic based systems to generate power, run irrigation pumping sets and home lighting and streetlights. In addition to offering subsidy on these products government is also offering training on PV technology, PV system designs and related fields. The programme of MNES comprises of promoting use of PV technology to provide lighting in villages in the form of : TABLE 1.1
Community lighting systems
Capacity usually 1KW to 2.5 KW
Portable solar lanterns
Small 10Wp SPV module connected to a 12V7AH battery lighting 7 W CFL lamp for 3 hours a day
Street lights
Built around a 75Wp SPV module charging a 100-130AH battery to run a 11W CFL lamp for dusk to daw dawn operation.
Fixed home lighting systems
Based
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on
35-50Wp
SPV
module,
powering powering two CFLs each of 9 or 11W to work 4-5 hours per day. Some systems also incorporate facility to run a small TV set or a fan from the power supply.
Water Pumping
Typically
1KW
DC
motor
based
pumping for shallow pumping.
1.2
WHY LED STREET LAMPS?
In today' today'ss world, world, the gradual gradual depletion depletion of energy energy and the gradual gradual deterior deteriorati ation on of environment has become a great challenge to us. LED is the most preferred green lighting source in the 21st century, which is the criterion of energy saving and environment protection protection.. Most of the countries in the world world have used the policy and rules to map out the spread plan and a revolution in the field of lighting industry is expected soon. In the past three years, we have invested tremendous amount of manpower and resources. Committed to develop new generation semiconductor LED lighting products. LED lamps need only 20% power as that of traditional bulbs and can generate 80 lm/w. These lamps have super long life up to 50,000 hours and 8 times the brightness than traditional light bulb. Now all this is no longer inconceivable, it has it has become a reality.
1.3
OBJECTIVES OF THE PROJECT
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The fundamental purpose of a Practice School is to prepare for employment in the chosen discipline at the conclusion of undergraduate studies. Study at university is enhanced by the opportunity to relate academic and professional aspects of engineering disciplines. 1.
To gain first-ha -hand experi erience nce of working as an engin gineering professional,
including the technical application of engineering methods. 2.
To work ork wi with othe otherr eng engiineer neeriing prof profes essi sion onal als. s.
3.
To expe experi rien ence ce the the dis disci cipl plin inee of of wor worki king ng in a pro profe fess ssio iona nall org organi aniza zati tion. on.
4.
To deve develo lop p techn echniical cal, inter nterpe perrsona sonall and and comm commun uniicati cation on skil kills, ls, bot both oral oral and
written. 5.
To obse observ rvee int inter erac acti tion onss of engi engine neer erss wit with h othe otherr pro profe fess ssio iona nall gro group ups. s.
6.
To obse observ rvee the the func functi tion onin ing g and and org organi aniza zati tion on of of bus busin ines esss and and comp compan anie ies. s.
7.
To get get expo expose sed d to engi engine neer erin ing g exper experie ienc ncee and know knowle ledg dgee which which is is requ requir ired ed in in
industry, where these are not taught in the lecture rooms. 8.
To appl apply y the the engi engine neer erin ing g know knowle ledg dgee taugh taughtt in the the lect lectur uree room roomss in real real indu indust stri rial al
situations. 9.
To use use the the exp exper erie ience nce gaine gained d from from the the Pra Pract ctic icee Scho School ol in in disc discus ussi sion onss held held in in the the
lecture rooms. 10. 10.
To get get a feel feel of the wor work env enviironm ronmen entt.
11.
To gain gain expe experie rience nce in writin writing g repo reports rts in engineer engineering ing works/ works/pro projec jects. ts.
8
12.
To get get expos exposed ed to to the the engi engine neer erss resp respon onsi sibi bili liti ties es and and eth ethic ics. s.
It is worth noting that many employers regard this period as a chance to assess new employees for future employment. Ability to take responsibility, make sound decisions and apply apply techn technic ical al skil skills ls will will be high highly ly rega regard rded ed.. Proj Projec ects ts can help help to eval evaluat uatee compan companie iess for for whic which h one one might might wish wish to work work,, or make make deci decisi sions ons about about fiel fields ds of engineering which one enjoys.
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2.1
LITERATURE REVIEW
ABOUT LEDs
A light-emitting diode (LED) is a semiconductor light semiconductor light source. LEDs are used as indicator lamps in many devices, and are increasingly used for lighting for lighting.. Introduced as a practical electronic component in 1962, early LEDs emitted low-intensity red light, but modern 9
versions are available across the visible, visible, ultraviolet and infrared wavelengths, with very high brightness. The LED is based on the semiconductor diode. diode. When a diode is forward biased (switched on), electrons are able to recombine with holes within the device, releasing energy in the form of photons. of photons. This effect is called electroluminescence and the color of the light (corresponding to the energy of the photon) is determined by the energy gap of the semiconductor. An LED is usually small in area (less than 1 mm2), and integrated optical components are used to shape its radiation pattern and assist in reflection. LEDs present many advantages over incandescent incandescent light sources including including lower energy consumption, consumption, longer lifetime longer lifetime,, improved robustness, smaller size, faster switching, and greater durability and reliabili reliability. ty. However, they are relatively relatively expensive and require require more precise current and heat management management than traditional light sources. Current LED products for general lighting are more expensive to buy than fluorescent lamp sources of comparable output.
2.1.1
Technology-Physics
Like a normal diode, the LED consists of a chip of semiconducting material doped with impurities to create a p-n junction. junction. As in other diodes, current flows easily from the pside, or anode or anode,, to the n-side, or cathode or cathode,, but not in the reverse direction. Charge-carriers — electrons electrons and holes —flow into the junction from electrodes with different voltages. When an electron meets a hole, it falls into a lower energy lower energy level, and releases energy in the form of a photon a photon..
10
The wavelength of the light emitted, and therefore its color, depends on the band gap energy of the materials materials forming forming the p-n junction. junction. In silicon or germanium diodes, the electrons electrons and holes recombine recombine by a non-radiat non-radiative ive transitio transition n which produces no optical optical emission, because these are indirect band gap materials. The materials used for the LED have a direct band gap with energies corresponding to near-infrared, visible or nearultraviolet light. LED development began with infrared and red devices made with gallium arsenide. arsenide. Advances Advances in materials science have made possible the production of devices with evershorter wavelengths, producing light in a variety of colors. LEDs are usually built on an n-type substrate, with an electrode attached to the p-type layer deposited on its surface. P-type substrates, while less common, occur as well. Many commercial LEDs, especially GaN/InGaN, also use sapphire substrate. Most materials used for LED production have very high refractive indices. indices. This means that that much much light light will will be reflec reflected ted back into into the materi material al at the material material/ai /airr surfac surfacee interface. Therefore Light extraction in LEDs is an important aspect of LED production, subject to much research and development.
2.1.2 2.1.2
Effici Eff icienc ency y and oper operati ationa onall param paramete eters rs
Typical indicator LEDs are designed to operate with no more than 30–60 milliwatts [mW] [mW] of electr electrica icall power. power. Around Around 1999, 1999, Philips Philips Lumileds Lumileds introduced introduced power LEDs capable of continuous use at one watt [W]. These LEDs used much larger semiconductor
11
die sizes to handle the large power inputs. Also, the semiconductor dies were mounted onto metal slugs to allow for heat removal from the LED die. One of the key advantages of LED-based lighting is its high efficiency, as measured by its light output per unit power input. White LEDs quickly matched and overtook the efficiency of standard incandescent lighting systems. In 2002, Lumileds made five-watt LEDs LEDs avai availa labl blee with with a luminous luminous efficacy efficacy of 18–22 18–22 lumens per per watt watt [lm/ [lm/W] W].. For For comparison, a conventional 60–100 W incandescent lightbulb produces around 15 lm/W, and standard fluorescent lights produce up to 100 lm/W. A recurring problem is that efficiency will fall dramatically for increased current. This effect is known as droop and effectively limits the light output of a given LED, increasing heating more than light output for increased current. In September 2003, a new type of blue LED was demonstrated by the company Cree, Inc. to provide 24 mW at 20 milliamperes [mA]. This produced a commercially packaged white light giving 65 lm/W at 20 mA, becoming the brightest white LED commercially available at the time, and more than four times as efficient as standard incandescents. In 2006 they demonstrated a prototype with a record white LED luminous efficacy of 131 lm/W at 20 mA. Also, Seoul Semiconductor has plans for 135 lm/W by 2007 and 145 lm/W by 2008, which would be approaching an order of magnitude improvement over standard incandescents and better even than standard fluorescents. Nichia Corporation has developed a white LED with luminous efficacy of 150 lm/W at a forward current of 20 mA. It should be noted that high-power (≥ 1 W) LEDs are necessary for practical general lighting applications. Typical operating currents for these devices begin at 350 mA. 12
Note that these efficiencies are for the LED chip only, held at low temperature in a lab. In a light lighting ing applic applicati ation, on, operati operating ng at higher higher temper temperatur aturee and with with drive drive circui circuitt losses losses,, efficiencie efficienciess are much lower. lower. United United States States Department Department of Energy (DOE) testing of commercial LED lamps designed to replace incandescent lamps or CFLs showed that average efficacy was still about 46 lm/W in 2009 (tested performance ranged from 17 lm/W to 79 lm/W). Cree issued a press release on February 3, 2010 about a laboratory prototype LED achieving 208 lumens per watt at room temperature. The correlated color temperature was reported to be 4579 K.
2.1. 2.1.3 3
Life Lifeti time me and and fail failur uree
Solid state devices such as LEDs are subject to very limited wear and tear if tear if operated at low currents and at low temperatures. Many of the LEDs produced in the 1970s and 1980s are still in service today. Typical lifetimes quoted are 25,000 to 100,000 hours but heat and current settings can extend or shorten this time significantly. The most common symptom of LED (and diode laser ) failure is the gradual lowering of light output and loss of efficiency. Sudden failures, although rare, can occur as well. Early red LEDs were notable for their short lifetime. With the development of high power LEDs the devices are subjected to higher junction temperatures and higher current densities than traditional devices. This causes stress on the material and may cause early light output degradation. To quantitatively classify lifetime in a standardized manner it has been suggested to use the terms L75 and L50 which is the time it will take a given
13
LED to reach 75% and 50% light output respectively. L50 is equivalent to the half-life of the LED. Like Like othe otherr ligh lighti ting ng devi device ces, s, LED LED perfo perform rman ance ce is temp temper erat atur uree depen dependen dent. t. Most Most manufacturers’ published ratings of LEDs are for an operating temperature of 25°C. LEDs used outdoors, such as traffic signals or in-pavement signal lights, and that are utilized in climates where the temperature within the luminaire gets very hot, could result in low signal intensities or even failure. LEDs LEDs mainta maintain in consist consistent ent light light output output even even in cold cold temper temperatu atures res,, unlike unlike tradit tradition ional al lighting methods. Consequently, LED technology may be a good replacement in areas such as supermarket freezer lighting and will last longer than other technologies. Because LEDs do not generate as much heat as incandescent bulbs, they are an energy-efficient technology to use in such applications such as freezers. On the other hand, because they do not generate much heat, ice and snow may build up on the LED luminaire in colder climates. This has been a problem plaguing airport runway lighting, although some research has been done to try to develop heat sink technologies in order to transfer heat to alternative areas of the luminaire.
2.1. 2.1.4 4
High High power ower LE LEDs Ds
High power LEDs from Philips Lumileds Lighting Company mounted on a 21 mm star shaped base metal core PCB. PCB. High power LEDs (HPLED) can be driven at currents from hundreds of mA to more than an ampere, compared with the tens of mA for other LEDs. Some can produce over a 14
thousand lumens. Since overheating is destructive, the HPLEDs must be mounted on a heat sink to allow for heat dissipation. If the heat from a HPLED is not removed, the device will burn out in seconds. A single HPLED can often replace an incandescent bulb in a flashlight, flashlight, or be set in an array to form a powerful LED lamp. lamp. Some well-known HPLEDs in this category are the Lumileds Rebel Led, Osram Opto Semiconductors Golden Dragon and Cree X-lamp. As of September 2009 some HPLEDs manufactured by Cree Inc. now exceed 105 lm/W (e.g. the XLamp XP-G LED chip emitting Cool White light) and are being sold in lamps intended to replace incandescent, halogen, and even fluorescent style lights as LEDs become more cost competitive. LEDs have been developed by Seoul Semiconductor that can operate on AC power without the need for a DC converter. For each half cycle part of the LED emits light and part is dark, and this is reversed during the next half cycle. The efficacy of this type of HPLED is typically 40 lm/W. A large number of LED elements in series may be able to operate directly from line voltage. In 2009 Seoul Semiconductor released a high DC voltage capable of being driven from AC power with a simple controlling circuit. The low power dissipation of these LEDs affords them more flexibly than the original AC LED design.
2.1. 2.1.5 5
Cons Consid ider erat atio ions ns for for use use
Power sources The current/voltage characteristic of an LED is similar to other diodes, in that the current is dependent exponentially on the voltage (see Shockley diode equation). equation). This means that 15
a small small change in voltage voltage can lead to a large change in current. If the maximum voltage rating is exceeded by a small amount the current rating may be exceeded by a large amount, potentially damaging or destroying the LED. The typical solution is therefore to use constant current power supplies, or driving the LED at a voltage much below the maximum rating. Since most household power sources (batteries, mains) are not constant current current sources, sources, most LED fixtures fixtures must include a power converter. converter. However, the I/V curve curve of nitridenitride-bas based ed LEDs LEDs is quite steep above the knee and gives gives an If of a few milliamperes at a Vf of 3 V, making it possible to power a nitride-based LED from a 3 V battery such as a coin cell without the need for a current limiting resistor.
2.1. 2.1.6 6
Elec Electr tric ical al Pola Polari rity ty
As with all diodes, current flows easily from p-type to n-type material. However, no current flows and no light is produced if a small voltage is applied in the reverse direction. If the reverse voltage becomes large enough to exceed the breakdown the breakdown voltage, voltage, a large current flows and the LED may be damaged. If the reverse current is sufficiently limited to avoid damage, the reverse-conducting LED is a useful noise diode. diode.
2.1.7
Safety
The vast majority of devices containing LEDs are "safe under all conditions of normal use", and so are classified as "Class 1 LED product"/"LED Klasse 1". At present, only a few LEDs—extremely bright LEDs that also have a tightly focused viewing angle of 8° or less—could, in theory, cause temporary blindness, and so are classified as "Class 2".In 16
general, laser safety regulations—and the "Class 1", "Class 2", etc. system—also apply to LEDs.
2.1. .1.8
Advantages
•
Efficiency: LEDs produce more light per watt than incandescent bulbs. Their
efficiency is not affected by shape and size, unlike Fluorescent light bulbs or tubes.
•
Color: LEDs can emit light of an intended color without the use of the color filters
that traditional lighting methods require. This is more efficient and can lower initial costs.
•
Size: LEDs can be very small (smaller than 2 mm2) and are easily populated onto
printed circuit boards.
•
On/Off On/Off time: LEDs LEDs light light up very very quickl quickly. y. A typica typicall red indicato indicatorr LED will will
achieve full brightness in microseconds. LEDs used in communications devices can have even faster response times.
•
Cycling: LEDs are ideal for use in applications that are subject to frequent on-off
cycling, unlike fluorescent lamps that burn out more quickly when cycled frequently, or HID lamps that require a long time before restarting.
•
Dimming: LEDs can very easily be dimmed either by pulse-width by pulse-width modulation or
lowering the forward current.
•
Cool light: In contrast to most light sources, LEDs radiate very little heat in the
form of IR that can cause damage to sensitive objects or fabrics. Wasted energy is dispersed as heat through the base of the LED. 17
•
Slow failure: LEDs mostly fail by dimming over time, rather than the abrupt b urn-
out of incandescent bulbs.
•
Lifetime: LEDs can have a relatively long useful life. One report estimates 35,000
to 50,000 hours of useful life, though time to complete failure may be longer. Fluorescent tubes tubes typica typicall lly y are rated at about about 10,000 10,000 to 15,000 15,000 hours, hours, depending depending partly partly on the conditions of use, and incandescent light bulbs at 1,000–2,000 hours.
•
Shock resistance: LEDs, being solid state components, are difficult to damage
with external shock, unlike fluorescent and incandescent bulbs which are fragile.
•
Focus Focus:: The The soli solid d packa package ge of the the LED LED can can be desi designe gned d to focu focuss its its ligh light. t.
Incandescent and fluorescent sources often require an external reflector to collect light and direct it in a usable manner.
•
2.1.1 .1.1
Toxicity: LEDs do not contain mercury, mercury, unlike fluorescent lamps. lamps.
Disa Disad dvantag tages
•
Some Fluorescent lamps can be more efficient.
•
High initial price: LEDs are currently more expensive, price per lumen, on an
initial capital cost basis, than most conventional lighting technologies. The additional expense partially stems from the relatively low lumen output and the drive circuitry and power supplies needed.
•
Temper Temperatu ature re depende dependence: nce: LED perfor performan mance ce largel largely y depends depends on the ambien ambientt
temper temperatu ature re of the operat operating ing enviro environme nment. nt. Over-d Over-dri rivin ving g the LED in high high ambien ambientt 18
temperatures may result in overheating of the LED package, eventually leading to device failure. failure. Adequate Adequate heat-sinking is requir required ed to maintai maintain n long long life. life. This This is especi especiall ally y important when considering automotive, medical, and military applications where the device must operate over a large range of temperatures, and is required to have a low failure rate.
•
Voltage sensitivity: LEDs must be supplied with the voltage above the threshold
and a current below the rating. This can involve series resistors or current-regulated power supplies.
•
Light quality: Most cool-white cool-white LEDs have spectra that differ significantly from a
black body radiator like the sun or an incandescent light. The spike at 460 nm and dip at 500 nm can cause the color of objects to be perceived be perceived differently under cool-white LED illumination than sunlight or incandescent sources, due to metamerism, metamerism, red surfaces being rendered particularly badly by typical phosphor based cool-white LEDs. However, the color rendering properties of common fluorescent lamps are often inferior to what is now available in state-of-art white LEDs.
•
Area light source: LEDs do not approximate a “point source” of light, but rather a
lambertian distribution. So LEDs are difficult to use in applications requiring a spherical light field. LEDs are not capable of providing divergence below a few degrees. This is contrasted with lasers, which can produce beams with divergences of 0.2 degrees d egrees or less.
2.1
LIGHTING
19
A street light, lamppost, street lamp, light standard, or lamp standard is a raised source of light on the edge of a road, which is turned on or lit at a certain time every night. Modern lamps may also have light-sensitive photocells to turn them on at dusk , off at dawn, dawn, or activate activate automatical automatically ly in dark weather dark weather . In older lighting this function would have been performed with the aid of a solar dial. dial. It is not uncommon for street lights to be on posts which have wires strung between them, such as on telephone poles or utility or utility poles. poles. Before incandescent lamps, gas lighting was employ employed ed in cities cities.. The earli earliest est lamps lamps required that a lamplighter tour the town at dusk, lighting each of the lamps, but later designs employed ignition devices that would automatically strike the flame when the gas supply was activated. The earliest of such street lamps were built in the Arab Empire, Empire, especially in Córdoba, Spain. Spain. The first modern street lamps, which used kerosene, were introduced in Lvov, Lvov, Poland in 1853. The first first electr electric ic street street light lighting ing employ employed ed arc lam lamps ps,, initially initially the 'Electric 'Electric candle', candle', 'Jablotchkoff candle' or 'Yablochkov or 'Yablochkov candle' developed by the Russian Pavel Yablochkov in 1875. This was a carbon arc lamp employing alternating current, which ensured that both electrodes were consumed at equal rates. Yablochkov candles were first used to light the Grands Magasins du Louvre, Louvre, Paris where 80 were deployed -- improvement which was one of the reasons why Paris earned its "City of Lights" nickname. Arc lights had two major disadvantages. First, they emit an intense and harsh light which, although useful at industrial sites like dockyards, was discomforting in ordinary city streets. Second, they are maintenance-intensive, as carbon electrodes burn away swiftly. With the development of cheap, reliable and bright incandescent light bulbs at the end of
20
the 19th century, they passed out of use for street lighting, but remained in industrial use longer. Incandescent lamps were primarily used for street lighting until the advent of highintensity discharge lamps. They were often operated in high-voltage series circuits. circuits. Series circuits were popular since the higher voltage in these circuits produced more light per watt consumed. Furthermore, before the invention of photoelectric controls, a single switch or clock could control all the lights in an entire district.
To avoid having the entire system go dark if a single lamp burned out, each street lamp was equipped with a device that ensured that the circuit would remain intact. Early series street lights were equipped with isolation transformers
[8]
that would allow current to pass
across across the transf transform ormer er whethe whetherr the bulb worked worked or not. not. Later Later the film cutout cutout was invented. The film cutout was a small disk of insulating film that separated two contacts connected to the two wires leading to the lamp. If the lamp failed (an open circuit), circuit), the current through the string became zero, causing the voltage of the circuit (thousands of volts) to be imposed across the insulating film, penetrating it (see Ohm's law). law). In this way, the failed lamp was bypassed and power restored to the rest of the district. The street light circuit contained an automatic voltage regulator, preventing the current from increasing as lamps burned out, preserving the life of the remaining lamps. When the failed lamp was replaced, a new piece of film was installed, once again separating the contacts in the cutout. This system was recognizable by the large porcelain insulator separating the lamp and reflector from the mounting arm. This was necessary because the
21
two contacts in the lamp's base may have operated at several thousand volts above ground/earth. Today, street lighting commonly uses high-intensity discharge lamps, lamps, often HPS high pressure sodium lamps. lamps. Such lamps provide the greatest amount of photopic photopic illumination for for the the leas leastt cons consum umpt ptio ion n of elec electr tric icit ity. y. Howe However ver when when scotopic scotopic// photopic photopic light calcul calculati ations ons are used, it can been been seen seen how inappropr inappropriat iatee HPS lamps lamps are for night night lighting. White light sources have been shown to double driver peripheral vision and increase driver brake reaction time at least 25%. When S/P light calculations are used, HPS lamp performance needs to be reduced by a minimum value of 75%. New street lighting technologies, such as LED or inductionlights, or inductionlights, emit a white light that provides high levels of scotopic lumens allowing street lights with lower wattages and lower photopic lumens to replace existing street lights. However, there have been no formal specifications written around Photopic/Scotopic adjustments for different types of light light source sources, s, causin causing g many many munici municipali palitie tiess and street street departm department entss to hold hold back back on implementation of these new technologies until the standards are updated. With the development of high efficiency and high power LEDs it has become possible to incorporate LEDs in lighting and illumination. Replacement light bulbs have been made as well as dedicated fixtures and LED lamps. lamps. LEDs are also being used now in airport and heliport lighting. LED airport fixtures currently include medium intensity runway lights, runway centerline lights and obstruction lighting.
2.2
LED STREET LIGHTS
22
•
An LED street street light (also called LED road lighting) lighting) is an integrated integrated LED (Light
Emitting Diode) light fixture that is used as street lighting. lighting. Because they are more energy efficient than other technologies used for street lighting, LED street lights can save on the cost of keeping streets well lit during the night.
•
An LED street light is an integrated light that uses LEDs as its light source. These
are considered integrated lights because the luminaries and the fixture are not separate parts. In manufacturing, the LED light cluster is sealed on a panel and then assembled to the LED panel with a heat sink to become an integrated lighting fixture.
•
A light-emitting-diode lamp is a solid-state lamp that uses light-emitting diodes
(LEDs) as the source of light. Since the light output of individual light-emitting diodes is small compared to incandescent and compact fluorescent lamps, multiple diodes are used together. LED lamps can be made interchangeable with other types. Most LED lamps must also include internal circuits to operate from standard AC voltage. LED lamps offer long life and high efficiency, but initial costs are higher than that of fluorescent lamps.
•
Light-emitting diode lamps have the characteristics of long life expectancy and
rela relati tivel vely y low low ener energy gy cons consum umpt ptio ion. n. The The LED LED sour source cess are are comp compac act, t, whic which h gives gives flexibility in designing lighting fixtures and good control over the distribution of light with small reflectors or lenses. LED lamps have no glass tubes to break, and their internal parts are rigidly supported, making them resistant to vibration and impact.
•
The primar primary y appeal appeal of LED street street lighti lighting ng is energy energy effici efficienc ency y compar compared ed to
incandescent bulbs of the same luminance. Research continues to improve the efficiency of newer models. One such advance can be found in a street light product created by Lighting Science Group. One model of LED street lights produced by this group is up to 23
60% more efficient than previous models, lasts for 12 years and allows for cost recovery through energy savings in only three years.
•
An LED street light based on a 901 milliwatt output LED can normally produce
the same amount of (or higher) luminance as a traditional light, but requires only half of the power consumption.
•
The lifespan of LED street lights is determined by its light output compared to its
original design specification. Once its brightness decreases by 70%, an LED street light is considered to be at the end of its life.
•
Most LED street lights have a lens on the LED panel, that is designed to cast its
light in a rectangular pattern, an advantage compared to traditional street lights, which typically have a reflector on the back side of a high-pressure sodium lamp.
•
LEDs LEDs have have a numb number er of usef useful ul prop proper erti ties es,, 3 of whic which h are are usef useful ul here here::
directionality, specific colour and efficiency.
•
In addition to the inherent efficiency of LEDs, street light can be made very
directional, casting light mostly along the roadway, with only a small amount down and none up. This This will will allow allow good good illum illuminat ination ion with with the least least light light genera generati tion, on, furthe further r reducing power consumption and saving more money.
•
In addition, by using separate red, green and blue elements, the colour can be
varied. By producing different colours at different times, colour vision can be helped while while protec protectin ting g night night vision vision.. At dawn/d dawn/dusk usk,, the lights lights product product a blue/g blue/gree reen n light light,, complementing the red glow of the low sun, helping colour vision. At night, the lights generate pink light, protecting night vision. Re d light on its own is too unnatural. u nnatural. 24
•
The LED Street Street light is embossed with transparent transparent glass and heavy metal which
has a high tensile strength.
2.3.1 Advantages of led streetlights
The operational life of current white LED lamps is 100,000 hours. This is 11 years of continuous operation, or 22 years of 50 per cent operation. The long operational life of an led led lamp lamp is a star stark k contr contras astt to the the aver averag agee life life of an inca incande ndesc scen entt bulb bulb,, which which is approximately 5000 hours. If the lighting device needs to be embedded into a very inacce inaccessi ssible ble place, place, using using LEDs LEDs would would virtua virtually lly elimin eliminate ate the need for routi routine ne bulb bulb replacement. Benefits Key advantages of quality LED street lights include:
•
Improved night visibility due to higher color rendering, higher color temperature
and increased illuminance uniformity.
•
Significantly longer lifespan
•
Lower energy consumption
•
Reduced maintenance costs
•
Instant-on with no run-up or re-strike delays
•
No mercury, lead or other known disposable hazards
25
•
Lower environmental footprint
•
An opportunity to implement programmable controls (e.g. bi-level lighting)
•
LED lights offer municipalities other cost advantages. Never will you have the
creepy flickering streetlamp with an LED light; there is no filament to burn out, reducing maintenance. LED lights are up to 10 times more efficient than incandescent lights because the heat in an LED is almost completely turned into light, not wasted as heat, so they last longer. Because LED lights are plastic rather than glass, they also are less likely to crack or shatter.
•
Instal Installi ling ng LED light lightss can be paired paired with with instal installin ling g comput computer er networ networks ks that that
respond to real-time conditions, changing the amount of streetlight as necessary. This allows cities to customize their lighting according to season, neighborhood safety, or storm conditions. To boot, the low energy cost of LED lighting makes it more feasible to fit streetlamps with mini solar cells themselves, taking them off the grid entirely
•
Regular streetlights are also the culprit of light pollution -- the glow that comes
from cities, so bright that it is observable by satellite. To the delight of astronomers everywhere, LED lights produce a more focused, spotlight-like beam. LED lights may also be coated with thin nanocrystals, nanocrystals, resulting in natural seeming light rather than fluorescent’s wash-out blue or sodium’s fuzzy yellow glow.
•
LED lights offer an array of other benefits. Because they don’t emit UV rays, they
don’t attract insects.
26
2.3.1.1Light pollution
In urban areas light pollution can hide the stars and interfere with astronomy. astronomy. In settings near astronomical telescopes and observatories, observatories, low pressure sodium lamps may be used. These lamps are advantageous over other lamps such as mercury and metal halide lamps beca becaus usee low low pres pressu sure re sodi sodium um lamp lampss emit emit lower lower inte intens nsit ity, y, monochromatic light. Observatories can filter the sodium wavelength out of their observations and virtually eliminate the interference from nearby urban lighting. The light pollution also disrupts the natural growing cycle of plants.
2.3.1Disadvantages
The major criticisms of LED street lighting are that it can actually cause accidents if misused, Dangers There are two optical phenomena that need to be recognized recogn ized in street light installations.
•
The loss of night of night vision because of the accommodation reflex of drivers' eyes is
the greatest danger. As drivers emerge from an unlighted area into a pool of light from a street light their pupils their pupils quickly constrict to adjust to the brighter light, but as they leave the pool of light the dilation of their pupils to adjust to the dimmer light is much slower, so they are driving with impaired vision. As a person gets older the eye's recovery speed gets slower, so driving time and distance under un der impaired vision increases.
•
Oncoming headlights are more visible against a black background than a grey
one. The contrast creates greater awareness of the oncoming vehicle. 27
•
Stray voltage is also a concern in many cities. Stray voltage can accidentally
electrify light poles and has the potential to injure or kill anyone who comes into contact with the pole. Some cities have employed the Electrified Cover Safeguard technology which sounds an alarm and flashes a light, to warn the public, when a pole becomes dangerously electrified. There are also physical dangers. Street light stanchions (poles) pose a collision risk to motorists. This can be reduced by designing them to break away when hit (frangible (frangible or collapsible supports), protecting them by guardrails, or marking the lower portions to increase increase their visibility visibility.. High winds or accumulated accumulated metal fatigue fatigue also occasionall occasionally y topple street lights.
2.1 2.1
COMP COMPAR ARIS ISON ON WIT WITH H DIFF DIFFER EREN ENT T TYPE TYPES S OF STR STREE EET T LIGH LIGHTS TS
FIG. 2.1
28
FIG.2.2
29
TABLE 2.1
30
TABLE 2.2
31
2.4. 2.4.1 1
Spec Sp ectr traa-ef effe fect ct fun funct ctio ion n
Man’s retina is a radiate receiver which is made up of subulate and bacilliform cells. Each cell has different character and function completely. The sensitization ability of bacilliform cells is much worse than the subulate cells, but they have different sensitivity to the light. light. When When illumi illuminate nate (dayt (daytime ime), ), subula subulate te cells cells operate operate on the vision vision,, when illuminate at dark, bacilliform cells operate on the vision, when illuminate at dark, bacilliform cells operate on the vision. To different wavelength spectrum, the sensitivity for man depends on the function of the wavelength called spectrum effect function.
32
Experiment shows, depend on the observation field is different; spectrum efficiency functi function on is differ different ent.. The intern internati ational onal lighti lighting ng commis commissio sion n (CIE) (CIE) determ determine ined d the spect spectru rum m effi effici cien ency cy funct functio ion n as pict pictur uree (one) (one),, form form pict pictur uree (one (one)) we can can see see th corresponding peak value wavelength of Photopic Vision V(λ) and Scotopic Vision V(λ)\ is different, the peak value of V(λ) is 555nm, while V(λ) is 507nm. FIG. 2.3
with the same distributing to the spectrum, the brightness is quite different between bright vision and dark vision. See picture (two), LED light dark vision is 2.35 times than the bright vision, while the dark vision is 0.94 times brighter than. Usually photics meterage equipment sense light in bright vision condition, while streetlight is effective at night (dark vision), so ht common illuminate date get to be revised. The revised coefficient of LED is 2.35, and the revised coefficient of sodium light is 0.94; so in the same condition, (the same meterage instrument), LED streetlight is 2.5 times brighter than sodium light. Accordi Accordingl ngly, y, to reach reach the same same bright brightnes ness, s, for LED street streetli light ght,, 40% illum illumina inatio tion n is needed of sodium light. 33
2.4. 2.4.2 2
Phot Photom omet etri ricc Comp Compar aris ison on
As far as eyes: LED streetlight is 2.5 times brighter than sodium light, in the same altitude. FIG. 2.4
2.1
PURPOSE
There are three distinct main uses of street lights, each requiring different types of lights and placement. Misuse of the different types of lights can make the situation worse by compromising visibility or safety.
34
2.5.1Beacon lights
A modest steady light at the intersection of two roads is an aid to navigation because it helps a driver see the location of a side road as they come closer to it and they can adjust their braking and know exactly where to turn if they intend to leave the main road or see vehicles or pedestrians. A beacon light's function is to say "here I am" and even a dim light provides enough contrast against the dark night to serve the purpose. To prevent the dangers caused caused by a car driving driving through a pool of light, a beacon light must never shine onto the main road, and not brightly onto the side road. In residential areas, this is usually the only appropriate lighting, and it has the bonus side effect of providing spill lighting onto onto any sidewa sidewalk lk there there for the benefit benefit of pedest pedestria rians. ns. On Inters Interstat tatee highway highwayss this this purpose is commonly served by placing reflectors at the sides of the road.
2.5.2Roadway lights
Street lights are not normally intended to illuminate the driving route (headlights (headlights are preferred), but to reveal signs and hazards outside of the headlights' beam. Because of the dangers discussed above, roadway lights are properly used sparingly and only when a particular situation justifies increasing the risk. This usually involves an intersection with several turning movements and much signage, situations where drivers must take in much information quickly that is not in the headlights' beam. In these situations (A freeway junction or exit ramp) the intersection may be lit so that drivers can quickly see all haza hazard rds, s, and and a well well desi design gned ed plan plan will will have have grad gradua uall lly y incr increa easi sing ng ligh lighti ting ng for for approximately a quarter of a minute before the intersection and gradually decreasing lighting after it. The main stretches of highways remain unlighted to preserve the driver's 35
night vision and increase the visibility of oncoming headlights. If there is a sharp curve where headlights will not illuminate the road, a light on the outside of the curve is often justified. If it is desired to light a roadway (perhaps due to heavy and fast multilane traffic), to avoid the dangers of casual placement of street lights it should not be lit intermittently, as this requires repeated eye readjustment which implies eyestrain and temporary blindness when entering and leaving light pools. In this case the system is designed to eliminate the need for headlights. This is usually achieved with bright lights placed on high poles at close regular intervals so that there is consistent light along the route. The lighting goes from curb to curb. Resea Researc rch h a few few year yearss ago sugg sugges este ted d that that by comp compar aris ison on to other other count countri ries es,, more more pedestrians are hit by motor vehicles at night in Britain. The theory behind this was that Britain almost exclusively, used low pressure sodium street lighting, (LPS); unlike the rest rest of the the worl world d that that use use merc mercur ury y vapou vapourr gas gas disc dischar harge ge ligh lighti ting. ng. This This was was most most noticeable when flying in from Europe at night and seeing a warm orange glow when approaching Britain. LPS lighting, being monochromatic, shows pedestrians as shadowy forms, unlike other forms of street lighting. In recognition of this, pedestrian crossings are now lit by additional "white" lighting, and sodium lighting is being replaced by modern types.
36
2.5.3Security lighting
FIG. 2.5 A sodium vapour light. light. This type is often used as security lighting. Security lighting is similar to high-intensity lighting on a busy major street, with no pools po ols of light and dark, but with the lighted area extending onto people's property, at least to their front door. This requires a different type of fixture and lens. The increased glare experie experience nced d by driver driverss going going throug through h the area might might be consid considere ered d a tradetrade-off off for increased increased security. security. This is what would normally normally be used along sidewalks sidewalks in dense areas of cities. Often unappreciated is that the light from a full moon is brighter than most security lighting.
37
3
3.1 3.1
RESEARCH METHODOLOGY
ILLU ILLUMI MINA NANC NCE E DIST DISTRI RIBU BUTI TION ON AT AT DIFF DIFFER EREN ENT T HEIG HEIGHT HTS S
FIG. 3.1
38
3.2 3.2
INTE INTEG GRATED ATED HIGH IGH POWE POWER R LE LED D STREE TREETL TLIG IGH HT INST INSTAL ALLA LAT TION ION
METHOD ➢
FIG 3.2 168W Figure
Integrated High Power LED streetlight Power Supply Cavity Structure and Connection Diagram FIG. 3.3
39
FIG. 3.4 Five common Formats to install streetlight
➢
FIG. 3.5 28W installation Method
40
FIG. 3.6 Anatomical Drawings
41
3.3 3.3
TROU TROUBL BLES ESHO HOOT OTIN ING G MET METHO HODS DS AND AND MAI MAINT NTEN ENAN ANCE CE
TABLE 3.1
FIG. 3.7
42
FIG. 3.8
FIG 3.9
43
3.4
SPECIFICATIONS
Top of Form
/Exporters_S /Exporters_Suppl uppl
12327 12327
Current
380 mA
LUX
12000 Lumens
Watt Consumption
38 Watts
At Height of
9 Meter
Voltage Range
60 v to 450 v
Application
Street Lights
Advantages LED lighting is totally new concept in power saving products, which consumes very low power is a true replacement of normal energy saving lighting products. It saves 50% more power than T5 or T8 tube type energy saving lightings. In first glan glance ce the the pric pricee seem seemss high higher er,, but but life life span span of this this ligh lighti ting ng syst system em is approxi approximat mately ely 50 times times higher higher than than the normal normal filam filament ent lighti lightings ngs.It .It is very very economical than other conventional or energy efficiency lighting systems. The feature of LED lighting is solid state in nature, vibration resistant & shock proof.
44
3.5
DUTY CYCLE:
The LED street lighting system is designed to be automatically switch ON at dusk, operate throughout the night and automatically switch OFF at the dawn. It is under the average daily insolation of 5 KWh /sq.m. on a horizontal surface.
3.6 3.6
LED STREET LIGHTS, EASY ASY SET-UP -UP AND AND MINIMU IMUM RUNNING
COSTS
LED High Power streetlights, named "Clarion" are new kids in town, ready to replace the existing high wattage light sources. As the name signifies "Loud and Clear", these lights are far superior than their existing counterparts and got the attitude to carry it for longer period of time. Street Lights are everywhere and if replaced with LED street lights could produce significant energy savings on a very large scale. The fixture casting is constructed of die-cast Aluminum, coated with special powder coating treatment resulting in a long lasting fixture. Flexible and adaptable to existing street lamp poles & existing electrical systems, LED Street Lights can be used at any scale and height.
3.6.1 Specifications
Operating Voltage : 220 Volt A.C. +/-15% 45
TABLE 3.2
3.6.2
Technic Tec hnical al require requiremen mentt of led led for villag villagee street street lighti lighting: ng:
These minimum technical specifications are for replacing the existing street lights in villages with LEDs.
TABLE 3.3
46
3.7
SOLAR LE LED ST STREET L LIIGHTING
Solar street street lighting lighting system is ideal for street lighting in remote remote villages. villages. The system system is provided with battery storage backup sufficient to operate the light for 10-11 hours daily. The system is provided with automatic ON/OFF time switch for dusk to dawn operation and overcharge / deep discharge prevention cut-off with LED indicators. 47
The SPV modules are reported to have a service life of 15-20 years. Tubular Batteries provided with the solar street lighting system require lower maintenance; have longer life and give better performance.
FIG. 3.10
FIG. 3.11
Approximate cost The approximate cost for the most common specification is around Rs 24,000. It varies based on models. Advantages
•
No requirement of electricity
•
Easy to install
•
Simple to operate and low maintenance cost
•
Eco friendly
48
•
This system is designed for outdoor application in un-electrified remote rural
areas. This system is an ideal application for campus and village street lighting. The system is provided with battery storage backup sufficient to operate the light for 10-11 hours daily. The system is provided with automatic ON/OFF time switch for dusk to down operation and overcharge / deep discharge prevention cut-off with LED indicators.
•
TABLE 3.4 Different Versions of Solar LED Street Lighting System
FIG.3.12 Light output comparison
49
3.7 3.7
TECH TE CHNI NICA CAL L INF INFOR ORMA MATI TION ON FOR FOR MAI MAIN N COM COMPO PONE NENT NTS S
• The Solar Module is manufactured with high efficiency solar cells assembled
and lami lamina nate ted d at high high temp temper erat atur uree on a tough toughen ened ed and and temp temper ered ed glas glasss with with high high transparency. The module typically has a lifespan of over 30- 50 years.
• The Regulator is a battery charge regulator with a microprocessor that gives
optimal functioning of the street light. Battery charge control with various charge regimes (cyclical, buffer and equalizing charge) in order to guarantee the maximum production and most efficient storage of energy from the solar module. Discharge control ensures optimum performance of the battery, switch off of the lamp if the battery reach a state 75% discharge.
• Light sensor for the automatic switch on and off the lamps after sunset and
automatic switch off at sunrise.
"PLUS" function which serves as an automatic increase of lighting time of the
lamp in accordance with the amount of energy that the battery has stored. This very important function allows adaptation of the period of lighting, dependent on the actual amount of energy captured by the solar module and stored stored in the battery during during the day. After the standard minimum period of 6 hours programmed, the microprocessor will verify the actual state of charge of the battery and, should it still have energy, it will keep the lamp on for the rest of the night.
• The regulator has a maximum capacity of 10 Amperes and is equipped with a
fuse to protect it from short circuit. It is designed to perform at extreme temperature and 50
humidity conditions and includes a temperature compensation device. It has signals for state of battery charge and eventual fails of the system, and ensures the optimal battery lifetime under all environmental and operational conditions.
• The DC/AC ballast serves the SOX lamp, transforming an input current at 12
Volts DC into an AC output of stabilized current at high frequency, suitable to power a large light bulb and typically able to guarantee a durability of over 25000 hours. This ballast can be positioned inside the lamp casing.
• The lamp is made of SOX 18W, 26W, 35W bulb, with a luminous flow of 2700
lumens, 3700 lumens, 5200 lumens. Typically the lamp is installed at about 6 meters from ground and its light generates an 18-20 meter diameter cone of light.
FIG.3.13
51
In general, the specifications of the parts are
•
74 Watt Solar PV Module
•
12 V, 75 Ah Tubular battery with battery box
•
Charge Controller cum inverter (20-35 kHz)
•
11 Watt CFL Lamp with fixtures
•
4 metre mild steel lamp post above ground level with weather proof paint and
mounting hardware.
4
4.1
CIRCUIT DIAGRAM
WORKING MODEL
FIG. 4.1
52
4.2
COMPONENT LIST
R1
-
100K
R2
-
22
C9 C10 C11 L1 L2 D1 D2 D3 D4 M1 IC
53
-
470 µF 1 µF 222 µF 1.2mH 1.2mH IN4007 X 4 4148 4148 TK431 IRF 840 UC 3842A
R3
-
100K
R4
-
22
R5
-
56
R6
-
5 .6 K
R7
-
47
R8
-
3 .3
R9
-
47K
R1 0
-
1K
R1 1
-
.68
R1 2
-
1K
R1 3
-
16K
R1 4
-
2. 2 K
R1 5
-
39K
C1
-
.1µF/275VAC
C2
-
22 µF/450VAC
C3
-
47 µ F/50VAC
C4
-
47 µF
54
C5
-
531 µF
C6
-
104 µF
C7
-
470 µF
C8
-
104 µF
4.3
SPECIFICATIONS
INPUT VOLTAGE
-
170-250V
LIGHT SOURCE
-
1W LED
NUMBER OF LEDs
-
4
LED TOTAL POWER
-
4W
CURRENT
-
380mA
LUX
-
400 lumen
EFFICIENCY
-
>85%
FREQUENCY
-
50 Hz
POWER FACTOR
-
>.95
WORK TEMPRATURE
-
-30 degree to +50 degree
55
LIFESPAN
-
>50,000 hours
FIG 4.2
56
57
FIG. 4.3 FIG.4.4
5 CONCLUSIONS
58
The challenging aim of providing light in rural areas can be achieved by producing energy locally. Photovoltaic systems offer the possibility of exploiting an energy source available everywhere
while at the same time respecting the environment. The storage
of the energy into batteries overcomes the intrinsic discontinuity of the solar energy. The use of LEDs, ever-growing in lighting solutions, seems the most appropriate choice for energy saving thanks to their high luminous efficiency. Moreover, the availability of different different LED drivers, drivers, with buck or boost configuration configuration,, provides provides flexibilit flexibility y in lighting lighting systems design and high efficient power conversion solutions.
6 BIBLIOGRA GRAPHY www.ledlighting-manufacturer.com/.../LED-news-Benefits-of-LED-streetlights featured.matternetwork.com/.../led-streetlights-a-bright-idea.cfm www.ledlightsorient.com/street-lights www.sptrading.co.in/led-street-lights. www.tradeindia.com/manufacturers/.../led-street-lights www.joliet-led-streetlight www.ecogeek.org/content/view/
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