study of solar panel and power generation

8/18/2019 Study of Solar Panel and Power Generation

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Solar Panel:-

Solar Panel is technically known PV panels or Photovoltaic panel. The term photovoltaic comingfrom two words i.e. photo means light and voltaic means electricity. It can convert from light

energy to electrical energy in terms of direct current (dc).But normal light can produce only

voltage and very less amount of current. But Sunlight produces oth voltage and current

efficiently due to presence of photon in sun light.

PV T!"#"$%&%'

Photovoltaic (PV) solar cells as they are often referred to are semiconductor devices that convert

sunlight into direct current (*#) electricity. 'roups of PV cells are electrically configured into

modules and arrays which can e used to charge atteries operate motors and to power anynumer of electrical loads. +ith the appropriate power conversion e,uipment PV systems can

produce alternating current (-#) compatile with any conventional appliances and operate

in parallel with and interconnected to the utility grid.

"IST% %/ P"%T%V%&T-I#

The first conventional photovoltaic cells were produced in the late 0123s and throughout the0143s were principally used to provide electrical power for earth5oriting satellites.

In the 0163s improvements in manufacturing performance and ,uality of PV modules helped to

reduce costs and opened up a numer of opportunities for powering remote terrestrialapplications including attery charging for navigational aids signals telecommunications

e,uipment and other critical low power needs. In the 0173s photovoltaic ecame a popular power source for consumer electronic devices

including calculators watches radios lanterns and other small attery charging applications.

/ollowing the energy crises of the 0163s significant efforts also egan to develop PV power

systems for residential and commercial uses oth for stand5alone remote power as well as for utility5connected applications. *uring the same period international applications for PV systems

to power rural health clinics refrigeration water pumping telecommunications and off5grid

households increased dramatically and remain a ma8or portion of the present world market for PV products. Today the industry9s production of PV modules is growing at appro:imately ;2

percent annually and ma8or programs in the


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Using solar panels is a very practical way to produce electricity for many applications. The obviouswould have to be off-grid living. Living off-grid means living in a location that is not serviced by themain electric utility grid. Remote homes and cabins benefit nicely from solar power systems. o longeris it necessary to pay huge fees for the installation of electric utility poles and cabling from the nearestmain grid access point. A solar electric system is potentially less e!pensive and can provide power for

upwards of three decades if properly maintained.

"esides the fact that solar panels make it possible to live off-grid, perhaps the greatest benefit thatyou would en#oy from the use of solar power is that it is both a clean and a renewable source of energy. $ith the advent of global climate change, it has become more important that we dowhatever we can to reduce the pressure on our atmosphere from the emission of greenhousegases.

%olar panels have no moving partsand re&uire little maintenance.They are ruggedly built and last for

decades when porperlymaintained.Last, but not least, of the benefits of solar panels andsolar power is that, once a systemhas paid for its initial installationcosts, the electricity it produces forthe remainder of the system'slifespan, which could be as much as()-*+ years depending on the&uality of the system, is absolutelyfree or grid-tie solar powersystem owners, the benefits beginfrom the moment the system comesonline, potentially eliminating

monthy electric bills or, and this isthe best part, actually earning thesystem's owner additional incomefrom the electric company.

The solar cells you would have seen on satellites, caculaters etc are photovoltaic cells or modulesmodules are a collection of solar cells electrically connected and #oined together in one frame/.0hotovoltaics, photo 1 light, voltaic 1 electricity/, convert the energy of sunlight directly intoelectricity. 2riginally e!pensive and only used in space, photovoltaics are now finding manyapplications on countless devices, buildings etc were ever remote or free and environmentallysustainable produced electricity is re&uired.

0hotovoltaic 03/ cells are made of special materials called semiconductors like silicon, which iscurrently the most commonly used. "asically, when light shines on the solar cell a percentage of thissolar energy is absorbed into the semiconductor material. This energy now inside the semiconductorknocks electrons loose allowing them to flow freely. 03 cells also all have one or more electric fields


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that force electrons freed by light absorption to flow in a certain direction. This flow of electrons is anelectrical current. 4etal contacts on the top and bottom of the 03 cell draw that current off to use topower e!ternal electrical products such as lights, calculators etc. This current ,combined with thecell's voltage which is a result of its built-in electric field or fields/,determines the power or wattage/that the solar cell can produce.

%olar panels collect clean renewable energy in the form of sunlight and convert that light intoelectricity which can then be used to provide power for electrical loads. %olar panels are comprised of several individual solar cells which are themselves composed of layers of silicon, phosphorous whichprovides the negative charge/, and boron which provides the positive charge/. %olar panels absorb thephotons and in doing so initiate an electric current. The resulting energy generated fromphotonsstriking the surface of the solar panel allows electrons to be knocked out of their atomic orbitsand released into the electric field generated by the solar cells.

An average home has more than enough roof area for the necessary number of solar panels to produceenough solar electricrity to supply all of its power needs. Assisted by an inverter, a device that convertsthe direct current or 56 current/, generated by a solar panel into alternating current or A6 current/,solar panel arrays can be si7ed to meet the most demanding electrical load re&uirements. The A6current can be used to power loads in your home or commercial building, your recreational vehicle or

your boat R384arine %olar 0anels/, your remote cabin or home, and remote traffic controls,telecommunications e&uipment, oil and gas flow monitoring, RTU, %6A5A, and much more.

How to test a Solar Panel?

4ost in the most people that need to set up solar panels at the roof of the properties consider that allthey must do is set up them, however they overlook about assessment them after which if a littlesomething won't perform ade&uately they must phone for that installers once again and using thismethod they reduce time and get stressed.

%olar panel assessment pertains to employing an amp meter at the panel. power is acknowledged forbeing measured in amperes. This factor may be accomplished with an amp meter. this kind of ae&uipment are heading to be connected towards bad and good terminals at the solar panel after which

the panel are heading to be sub#ected towards sunlight. 9n purchase to guard by yourself from in#uriesand protected the amp meter from any destruction you really should (st price the meter greatercompared to solar panel is. The amp meter will present you on its display :the brief circuit current'.This are heading to be the level of electric present-day that ( could assume out of your panels to give.2 program everything is established by how powerful was the sunshine so it can be indicted toconduct your solar panel assessment when there is ordinarily a complete sunshine outside.

"esides employing an amp meter you'll be in a position to decide the energy yield of your respectivesolar panel by employing an additional strategy that implies measuring the resistor's voltage. becauseof this solar panel assessment process you'll re&uire a electronic multi-meter that actions the 56voltage/ and numerous resistors. subse&uent to ac&uiring every one among the essentialmeasurements you'll be in a position to use this formulation for calculating the energyoutput; present-day e&uals 3oltage 8 Resistance. subse&uent to that ( could constitute a

overall performance graphic by


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plotting the energy output.


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%ight including sunlight is sometimes described as particles called &photons.& As

sunlight strikes a photo'oltaic cell photons mo'e into the cell.

hen a photon strikes an electron it dislodges it lea'ing an empty &hole&. #he

loose electron mo'es toward the top layer of the cell. As photons continue to enter

the cell electrons continue to be dislodged and mo'e upwards.

f an electrical path e*ists outside the cell between the top grid and the back plane

of the cell a +ow of electrons begins. %oose electrons mo'e out the top of the cell

and into the e*ternal electrical circuit. ,lectrons from further back in the circuit

mo'e up to ll the empty electron holes.

ost cells produce a 'oltage of about one-half 'olt regardless of the surface area of the cell. owe'er the larger the cell the more current it will produce.

#he resistance of the circuit of the cell will a/ect the current and 'oltage. #he

amount of a'ailable light a/ects current production. #he temperature of the cell

a/ects its 'oltage.

0egardless of si1e a typical silicon PV cell produces about 2.3 4 2.5 'olt 67 under

open-circuit no-load conditions. #he current (and power) output of a PV cell depends

on its e/iciency and si1e (surface area) and is proportional to the intensity of sunlight striking the surface of the cell. 8or e*ample under peak sunlight conditions

a typical commercial PV cell with a surface area of 952 cm:; ( watts.


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TP!S %/ PV #!&&S

#he four general types of photo'oltaic cells are?

• "ingle-crystal silicon.

• Polycrystalline silicon (also known as multicrystalline silicon).

• 0ibbon silicon.

• Amorphous silicon (abbre'iated as &a"i& also known as thin lm silicon).

Single-crystal silicon:

Most photovoltaic cells are single-crystal types. To make them, silicon

is purified, melted, and crystallized into ingots. The ingots are sliced into thin wafers to make

individual cells. The cells have a uniform color, usually blue or black.


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Polycrystalline silicon:

Polycrystalline cells are manufactured and operate in a similar manner. The difference is that

lower cost silicon is used. This usually results in slightly lower efficiency, but

polycrystalline cell manufacturers assert that the cost benefits outweigh the efficiency

losses. The surface of polycrystalline cells has a random pattern of crystal borders

instead of the solid color of single crystal cells.

Ribbon silicon:

@rowing a ribbon from the molten silicon instead of an ingot makes ribbon-

type photo'oltaic cells. #hese cells operate the same as single and polycrystal cells.

#he anti-re+ecti'e coating used on most ribbon silicon cells gi'es them a

prismatic rainbow appearance.


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Amorphous or thin film silicon:

#he pre'ious three types of silicon used for photo'oltaic cells ha'e a

distinct crystal structure. Amorphous silicon has no such structure. Amorphous

silicon is sometimes abbre'iated &a"i& and is also called thin lm silicon.

Amorphous silicon units are made by depositing 'ery thin layers of 'apori1ed silicon

in a 'acuum onto a support of glass plastic or metal.

P"%T%V%-&T-I# >%*


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7onsider && is the abbre'iation for current e*pressed in amps. &V& is used for

'oltage in 'olts and &0& is used for resistance in ohms.

A photo'oltaic module will produce its ma*imum current when there is essentially

no resistance in the circuit. #his would be a short circuit between its positi'e and

negati'e terminals.

#his ma*imum current is called the short circuit current abbre'iated (sc). hen the

module is shorted the 'oltage in the circuit is 1ero.7on'ersely the ma*imum

'oltage is produced when there is a break in the circuit. #his is called the open

circuit 'oltage abbre'iated V(oc). nder this condition the resistance is innitely

high and there is no current since the circuit is incomplete.

#hese two e*tremes in load resistance and the whole range of conditions in

between them are depicted on a graph called a -V (current-'oltage) cur'e. 7urrent

e*pressed in amps is on the 'ertical B-a*is. Voltage in 'olts is on the hori1ontal C-

a*is (8igure 9).

A typical current 'oltage cur'e

As you can see in 8igure 9 the short circuit current occurs on a point on the cur'e

where the 'oltage is 1ero. #he open circuit 'oltage occurs where the current is 1ero.

#he power a'ailable from a photo'oltaic module at any point along the cur'e is

e*pressed in watts. atts are calculated by multiplying the 'oltage times the

current (watts D 'olts * amps or D VA).

-t the short circuit current point the power output is Aero since the voltage is Aero.-t the opencircuit voltage point the power output is also Aero ut this time it is ecause the current is Aero.


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#here is a point on the &knee& of the cur'e where the ma*imum power output is

located. #his point on our e*ample cur'e is where the 'oltage is 9E 'olts and the

current is ;.3 amps. #herefore the ma*imum power in watts is 9E 'olts times ;.3

amps e$ualing =;.3 watts.

#he power e*pressed in watts at the ma*imum power point is described as peak

ma*imum or ideal among other terms. a*imum power is generally abbre'iated

as & (mp).& Various manufacturers call it ma*imum output power output peak

power rated power or other terms.

#he current-'oltage (-V) cur'e is based on the module being under standard

conditions of sunlight and module temperature. t assumes there is no shading on

the module.

"tandard sunlight conditions on a clear day are assumed to be 9222 watts of solar

energy per s$uare meter (9222 Fm;or lkFm;). #his is sometimes called &one

sun& or a &peak sun.& %ess than one sun will reduce the current output of the

module by a proportional amount. 8or e*ample if only one-half sun (322 Fm;) is

a'ailable the amount of output current is roughly cut in half (8igure ;)

A #ypical 7urrent-Voltage 7ur'e at Gne "un and Gne-half "un

8or ma*imum output the face of the photo'oltaic modules should be pointed asstraight toward the sun as possible.

Hecause photo'oltaic cells are electrical semiconductors partial shading of the

module will cause the shaded cells to heat up. #hey are now acting as ineIcient

conductors instead of electrical generators. Partial shading may ruin shaded cells.


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Partial module shading has a serious e/ect on module power output. 8or a typical

module completely shading only one cell can reduce the module output by as much

as >2J (8igure K). Gne or more damaged cells in a module can ha'e the same

e/ect as shading.

A #ypical 7urrent-Voltage 7ur'e for an nshaded odule and for a odule with Gne

"haded 7ell.

#his is why modules should be completely unshaded during operation. A shadow

across a module can almost stop electricity production. #hin lm modules are not as

a/ected by this problem but they should still be unshaded.

odule temperature a/ects the output 'oltage in'ersely. igher moduletemperatures will reduce the 'oltage by 2.2= to 2.9 'olts for e'ery one-7elsius

degree rise in temperature (2.2=VF27 to 2.9VF27). n 8ahrenheit degrees the

'oltage loss is from 2.2;; to 2.235 'olts per degree of temperature rise (8igure =).


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A #ypical 7urrent-Voltage 7ur'e for a odule at ;3 ฐ 7 (EE ฐ 8) and >3 ฐ7 (9>3 ฐ 8)

#his is why modules should not be installed +ush against a surface. Air should be

allowed to circulate behind the back of each module so itLs temperature does not

rise and reducing its output. An air space of =-5 inches is usually re$uired to pro'ide

proper 'entilation.

#he last signicant factor that determines the power output of a module is the

resistance of the system to which it is connected. f the module is charging a

battery it must supply a higher 'oltage than that of the battery.

f the battery is deeply discharged the battery 'oltage is fairly low. #he photo'oltaic

module can charge the battery with a low 'oltage shown as point M9 in 8igure 3. As

the battery reaches a full charge the module is forced to deli'er a higher 'oltage

shown as point M;. #he battery 'oltage dri'es module 'oltage.

Gperating Voltages 6uring a Hattery 7harging 7ycle

,'entually the re$uired 'oltage is higher than the 'oltage at the moduleLs

ma*imum power point. At this operating point the current production is lower than

the current at the ma*imum power point. #he moduleLs power output is also lower.

#o a lesser degree when the operating 'oltage is lower than that of the ma*imum

power point (point M9) the output power is lower than the ma*imum. "ince the

ability of the module to produce electricity is not being completely used whene'er it

is operating at a point fairly far from the ma*imum power point photo'oltaic

modules should be carefully matched to the system load and storage.


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sing a module with a ma*imum 'oltage which is too high should be a'oided

nearly as much as using one with a ma*imum 'oltage which is too low.

#he output 'oltage of a module depends on the number of cells connected in series.

#ypical modules use either K2 K; KK K5 or == cells wired in series.

#he modules with K2-K; cells are considered self-regulating modules. K5 cell

modules are the most common in the photo'oltaic industry. #heir slightly higher

'oltage rating 95.E 'olts allows the modules to o'ercome the reduction in output

'oltage when the modules are operating at high temperatures.

odules with KK - K5 cells also ha'e enough surplus 'oltage to e/ecti'ely charge

high antimony content deep cycle batteries. owe'er since these modules can

o'ercharge batteries they usually re$uire a charge controller. 8inally == cell

modules are a'ailable with a rated output 'oltage of ;2.K 'olts. #hese modules are

typically used only when a substantially higher 'oltage is re$uired.

As an e*ample if the module is sometimes forced to operate at high temperaturesit can still supply enough 'oltage to charge 9;-'olt battery.

Another application for == cell modules is a system with an e*tremely long wire run

between the modules and the batteries or load. f the wire is not large enough it

will cause a signicant 'oltage drop. igher module 'oltage can o'ercome this

problem.

t should be noted that this approach is similar to putting a larger engine in a car

with locked brakes to make it mo'e faster. t is almost always more cost e/ecti'e to

use an ade$uate wire si1e rather than to o'ercome 'oltage drop problems with

more costly == cell modules.

P"%T%V%&T-I# --S

In many applications the power availale from one module is inade,uate for the load. Individual

modules can e connected in series parallel or oth to increase either output voltage or current.This also increases the output power. +hen modules are connected in parallel the current

increases. /or e:ample three modules which produce 02 volts and amps each connected in

parallel will produce 02 volts and 1 amps (/igure 4).


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#hree odules 7onnected in Parallel

f the system includes a battery storage system a re'erse +ow of current from the

batteries through the photo'oltaic array can occur at night. #his +ow will drainpower from the batteries.

A diode is used to stop this re'erse current +ow. 6iodes are electrical de'ices which

only allow current to +ow in one direction (8igure E). A blocking diode is shown in

the array in 8igure E.

.

Hasic Gperation of a 6iode

Hecause diodes create a 'oltage drop some systems use a controller which opens

the circuit instead of using a blocking diode.

f the same three modules are connected in series the output 'oltage will be =3

'olts and the current will be K amps.


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f one module in a series string fails it pro'ides so much resistance that other

modules in the string may not be able to operate either. A bypass path around the

disabled module will eliminate this problem (8igure >). #he bypass diode allows the

current from the other modules to +ow through in the &right& direction.

any modules are supplied with a bypass diode right at their electrical terminals.

%arger modules may consist of three groups of cells each with its own bypass

diode.

Huilt in bypass diodes are usually ade$uate unless the series string produces =>

'olts or higher or serious shading occurs regularly.

7ombinations of series and parallel connections are also used in arrays (8igure ). f

parallel groups of modules are connected in a series string large bypass diodes are

usually re$uired.

#hree odules 7onnected in "eries with a Hlocking 6iode and Hypass 6iodes


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#wel'e odules in a Parallel-"eries Array with Hypass 6iodes and solation 6iodes

TP!S %/ --S

Flat-plate stationary arrays

Stationary arrays are the most common. Some allow ad8ustments in their tilt angle from the

horiAontal. These changes can e made any numer of times throughout the year although theyare normally changed only twice a year. The modules in the array do not move throughout theday (/igure 03). -lthough a stationary array does not capture as much energy as a tracking array

that follows the sun across the sky and more modules may e re,uired there are no moving

parts to fail. This reliaility is why a stationary array is often used for remote or dangerouslocations.


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Ad!ustable Array #ilted for "ummer and inter "olar Angles

ortable arrays- portale array may e as small as a one s,uare foot module easily carried y one person to

recharge atteries for communications or flashlights. They can e mounted on vehicles to

maintain the engine attery during long periods of inactivity. &arger ones can e installed ontrailers or truck eds to provide a portale power supply for field operations (/igures 00)


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PV CELLS

A solar cell is a de'ice that con'erts the energy of sunlight directly into electricity

by the photo'oltaic e/ect. "ometimes the term solar cell is reser'ed for de'ices

intended specically to capture energy from sunlight such as solar panels and solarcells while the term photovoltaic cell is used when the light source is unspecied.

Assemblies of cells are used to make solar panels solar modules or photo'oltaic

arrays. Photovoltaic’s is the eld of technology and research related to the

application of solar cells in producing electricity for practical use. #he energy

generated this way is an e*ample of solar energy (also known as solar power ).

Photo'oltaic cells are manufactured by using di/erent materials with di/erent

process of making. ,ach type has itOs own ad'antages and disad'antages gi'ing

the end user a lot of choices so as to consider di/erent parameters.

TP!S %/ PV #!&&SC

#here are four types of photo'oltaic cells? multicrystalline silicon monocrystalline

silicon ribbon silicon and thin-lm.

>%$%#ST-&&I$! PV #!&&S

M!"#F!$T#%&"' %($)**

#he starting material is lumps of chemically pure polycrystalline silicon of a $uality

close to semiconductor-grade produced by the "iemens process. #he traditional

route for monocrystalline wafers is the 71ochralski process in which a single crystal

of up to about 932mm diameter is pulled from molten "i held in a large heated

$uart1 crucible. n the more recently de'eloped method "i is cast in a re-useable

graphite mould to produce blocks of multicrystalline silicon (cubes of o'er 2.3m

dimensions). hen sawn into bars and then wafers (!ust bigger than a compact

disc) using a wire saw the cleaned product is ready for cell manufacturing.

"ingle crystal or monocrystalline wafers are made using the 71ochralski process.

Czochralski process:


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igh-purity semiconductor-grade silicon (only a few parts per million of impurities)

is melted down in a crucible which is usually made of $uart1. 6opant impurity

atoms such as boron or phosphorus can be added to the molten intrinsic silicon in

precise amounts in order to dope the silicon thus changing it into n-type or p-type

e*trinsic silicon. #his in+uences the electronic properties of the silicon. A precisely

oriented seed crystal mounted on a rod is dipped into the molten silicon. #he seedcrystalLs rod is 'ery slowly pulled upwards and rotated at the same time. Hy

precisely controlling the temperature gradients rate of pulling and speed of

rotation it is possible to e*tract a large single-crystal cylindrical ingot from the

melt. n'estigating and 'isuali1ing the temperature and 'elocity elds during the

crystal growth process can a'oid occurrence of unwanted instabilities in the melt.

#his process is normally performed in an inert atmosphere such as argon and in an

inert chamber such as $uart1.

6ue to the eIciencies that can be gained by the adoption of common waferspecications the semiconductor industry has for some time used wafers with

standardi1ed dimensions. 7urrently high-end de'ice manufacturers use ;22 mm

and K22 mm diameter wafers. #he crystal ingots from which these wafers are sliced

can be up to ; meters in length weighing se'eral hundred kilograms. %arger wafers

allow impro'ements in manufacturing eIciency as more chips can be fabricated on

each wafer so there has been a steady dri'e to increase silicon wafer si1es. #he

ne*t step up =32 mm is currently scheduled for introduction in ;29;. "ilicon wafers

are typically about 2.;42.E3 mm thick and can be polished to a 'ery high +atness

for making integrated circuits or te*tured for making solar cells.

#he process begins when the chamber is heated up to appro*imately 9322 degrees7elsius to melt the silicon. hen the silicon is fully melted a small seed crystal

mounted on the end of a rotating shaft is slowly lowered until it !ust dips below the

surface of the red-hot molten silicon. #he shaft rotates counterclockwise and the

crucible rotates clockwise. #he rotating rod is then drawn upwards 'ery slowly

allowing a roughly cylindrical boule to be formed. #he boule can be from one to two

meters depending on the amount of silicon in the crucible.

n the early days of the technology the boles were smaller only a few inches wide.

ith increasing technology nowadays up to K22 mm (9;-inch)- wide boules can be

grown. #he width is controlled by precise control of the temperature the speeds of

rotation and how fast the seed holder is withdrawn. idths of =22 mm (95 inches)

are e*pected in the ne*t se'eral years. #his is one reason for the rapidly decreasing

cost of chips in recent years because more %" chips can be created from a single

wafer with the same number of fabrication process steps.


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#he electrical characteristics of the silicon are controlled by adding material like

phosphorus or boron to the silicon before it is melted. #he added material is called

dopant and the process is called doping.

hen silicon is grown by the 71ochralski method the melt is contained in a silica

($uart1) crucible. 6uring growth the walls of the crucible dissol'e into the melt and

71ochralski silicon therefore contains o*ygen at a typical concentration of 929> cmK.

G*ygen impurities can ha'e benecial e/ects. 7arefully chosen annealing

conditions can allow the formation of o*ygen precipitates. #hese ha'e the e/ect of

trapping unwanted transition metal impurities in a process known as gettering.

Additionally o*ygen impurities can impro'e the mechanical strength of silicon

wafers by immobili1ing any dislocations that may be introduced during de'ice

processing. t was e*perimentally shown in the 92s that the high o*ygen

concentration is also benecial for radiation hardness of silicon particle detectors

used in harsh radiation en'ironment. #herefore radiation detectors made of

71ochralski- and agnetic 71ochralski-silicon are considered to be promising

candidates for many future high-energy physics e*periments. t has also beenshown that presence of o*ygen in silicon increases impurity trapping during post-

implantation annealing processes.

owe'er o*ygen impurities can react with boron in an illuminated en'ironment

such as e*perienced by solar cells. #his results in the formation of electrically acti'e

boron4o*ygen comple* that detracts from cell performance. odule output drops by

appro*imately KJ during the rst few hours of light e*posure.

M#+T&$%*T!++&") $)++*

Techni,ues for the production of multicrystalline silicon are more simple and therefore cheaper

than those re,uired for single crystal material. "owever the material ,uality of multicrystallinematerial is lower than that of single crystalline material due to the presence of grain oundaries.

'rain oundaries introduce high localised regions of recomination due to the introduction of

e:tra defect energy levels into the and gap thus reducing the overall minority carrier lifetimefrom the material. In addition grain oundaries reduce solar cell performance y locking carrier

flows and providing shunting paths for current flow across the p-n 8unction.

Manufacturing rocess

The feedstock (made y purification of silicon or y alternative refining methods) is charged in asilicon nitride coated ,uartA crucile and heated until all the silicon is melted. "eat is then

e:tracted from the ottom of the crucile y moving the heat Aone up compared to the crucile

and ? or cooling the ottom of the crucile. %ften the crucile is lowered away from the heatAone and simultaneously the ottom is revealed to a cooling source.


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- temperature gradient is created in the melt and the solidification will start at the ottom and

crystals will grow upwards and grain oundaries will grow parallel to the solidificationdirection. To otain a directional solidification the solidification heat must e transported through

the steadily growing layer of solid silicon. It is necessary to maintain a net heat flu: over the

solid5li,uid interface and the temperature at the lower part of the crucile must e decreased

according to the increase in solid silicon thickness to maintain a steady growth rate. The growthrate is proportional to the temperature gradient difference etween the solid and the li,uid

silicon.

Impurity *istriution in *irectionally Solidified IngotsC

6ue to the fact that most elements are more soluble in li$uid than in solid silicon

impurities dissol'ed in the melt will segregate and the element concentration in the

ingot will in most cases increase upwards in the ingot following "cheilOs e$uation

when the melt solidies from the bottom and up.

The e:ponential distriution will create a heavily contaminated thin layer at the top of the

resulting ingot.

The Scheil e,uation assumes no diffusion in the solid state complete mi:ing in the li,uid stateand e,uilirium at the solid?li,uid interface. If convection is not sufficient to provide complete

mi:ing in the li,uid phase solute atoms are re8ected y the advancing solid at a greater rate than

they can diffuse into the ulk of the melt. - concentration gradient is thus developed ahead of thesolid. This enriched region will determine the rate of solute incorporation into the solid front.

This region is called a diffusion oundary layer. Scheil9s e,uation is still valid if an effective

distriution coefficient is used.

Forming of Precipitates:

Precipitates may form after saturation is met and Scheil9s e,uation will no longer e valid. The

amount of super saturation needed for precipitates to form will vary with the chemical

composition and the growth conditions in the system.

Diffusion of &mpuritiesC

In addition to the Scheil distriution the impurity distriution will depend on diffusion.Impurities will diffuse into the solidified silicon from the crucile walls and ottom as well as

from the coating. Back5diffusion can also occur as impurities diffuse from the heavily

contaminated top layer ack into the ulk material after solidification or from the oundarylayer during solidification. Both in5diffusion from the crucile and coating and ack5diffusion

are temperature dependent and the impurity distriution varies with varying temperature profile

during growth and the suse,uent cooling.

Boron ope! Silicon:

Boron is an acceptor in silicon and multicrystalline silicon ingots made y directional

solidification are often pre5doped with oron. - small amount of oron is added together with the

feedstock prior to melting and solidification. Boron is most commonly used ecause it is the


22/42

doping element with the distriution coefficient closest to 0 (k3 D 3.7). The distriution profile

will thus not vary as much with height as the other doping elements.

T/&" F&+M *(+!% $)++

- thin5film solar cell (T/S#) also called a thin5film photovoltaic cell (T/PV) is a solar cell that

is made y depositing one or more thin layers (thin film) of photovoltaic material on a sustrate.

The thickness range of such a layer is wide and varies from a few nanometers to tens of micrometers.

>any different photovoltaic materials are deposited with various deposition methods on a varietyof sustrates. Thin5film solar cells are usually categoriAed according to the photovoltaic material

usedC

• Amorphous silicon (a-"i) and other thin-lm silicon (#8-"i)

• 7admium #elluride (7d#e)

• 7opper indium gallium selenide (7" or 7@")

• 6ye-sensiti1ed solar cell (6"7) and other organic solar cells

Design and fabrication

The silicon is mainly deposited y chemical vapor deposition typically plasma5enhanced (P!5

#V*) from silane gas and hydrogen gas. %ther deposition techni,ues eing investigated include

sputtering and hot wire techni,ues.

The silicon is deposited on glass plastic or metal which has een coated with a layer of transparent conducting o:ide (T#%).

Polysilicon deposition or the process of depositing a layer of polycrystalline silicon on a

semiconductor wafer is achieved y pyrolyAing silane (Si"E) at 273 to 423 F#. This pyrolysis process releases hydrogen.

Polysilicon layers can e deposited using 033G silane at a pressure of ;2H03 Pa (3.; to 0.3Torr) or with ;3H3G silane (diluted in nitrogen) at the same total pressure. Both of these

processes can deposit polysilicon on 03H;33 wafers per run at a rate of 03H;3 nm?min and with

thickness uniformities of 2G. #ritical process variales for polysilicon deposition include

temperature pressure silane concentration and dopant concentration. +afer spacing and loadsiAe have een shown to have only minor effects on the deposition process. The rate of

polysilicon deposition increases rapidly with temperature since it follows -rrhenius ehavior

that is deposition rate D -Je:p(H,!a?kT) where , is electron charge and k is the BoltAmannconstant. The activation energy (!a) for polysilicon deposition is aout 0.6 eV. Based on this

e,uation the rate of polysilicon deposition increases as the deposition temperature increases.

There will e a minimum temperature however wherein the rate of deposition ecomes faster than the rate at which unreacted silane arrives at the surface. Beyond this temperature the

deposition rate can no longer increase with temperature since it is now eing hampered y lack


23/42

of silane from which the polysilicon will e generated. Such a reaction is then said to e Kmass5

transport5limited.K +hen a polysilicon deposition process ecomes mass5transport5limited thereaction rate ecomes dependent primarily on reactant concentration reactor geometry and gas

flow.

+hen the rate at which polysilicon deposition occurs is slower than the rate at which unreacted

silane arrives then it is said to e surface5reaction5limited. - deposition process that is surface5

reaction5limited is primarily dependent on reactant concentration and reaction temperature.*eposition processes must e surface5reaction5limited ecause they result in e:cellent thickness

uniformity and step coverage. - plot of the logarithm of the deposition rate against the reciprocal

of the asolute temperature in the surface5reaction5limited region results in a straight line whoseslope is e,ual to H,!a?k.

-t reduced pressure levels for V&SI manufacturing polysilicon deposition rate elow 262 F# is

too slow to e practical. -ove 423 F# poor deposition uniformity and e:cessive roughness will e encountered due to unwanted gas5phase reactions and silane depletion. Pressure can e varied

inside a low5pressure reactor either y changing the pumping speed or changing the inlet gas

flow into the reactor. If the inlet gas is composed of oth silane and nitrogen the inlet gas flowand hence the reactor pressure may e varied either y changing the nitrogen flow at constant

silane flow or changing oth the nitrogen and silane flow to change the total gas flow while

keeping the gas ratio constant.

Polysilicon doping if needed is also done during the deposition process usually y adding

phosphine arsine or diorane. -dding phosphine or arsine results in slower deposition while

adding diorane increases the deposition rate. The deposition thickness uniformity usuallydegrades when dopants are added during deposition.

*epending upon the efficiency re,uired these dopants are removed using several techni,ues.

!M(%/(#* *&+&$(" $)++*

-morphous Silicon cells use layers of a5Si only a few micrometers thick attached to an

ine:pensive acking such as glass fle:ile plastic or stainless steel. This means that they use

less than 0G of the raw material (silicon) compared standard crystalline Silicon (c5Si) cellsleading to a significant cost saving.

"#$%F#C&%R'$( PR)CESSC

-morphous silicon is gradually degraded y e:posure to light y phenomena called theStaeler5+ronski !ffect (S+!). S+! affects the power output of a5Si modules y as much as

03G. This light induced degradation is reduced y depositing the layers of the cell using highhydrogen dilution and y making cominations (alloys) of different types of cells. Because of

S+! a5Si cells are rated in the stailiAed condition which occurs after aout 033 hourse:posure to light.


24/42

light to e asored. Thus an ultra5thin amorphous silicon film of less than 0Lm can e

produced and used for power generation. This film ecause it is not crystalline and is so thinwill not reak when it is fle:ed thus allowing it to e deposited on fle:ile sustrates. Because

of the fle:aility of the cell and the sustrates a5Si producers are ale to use automated @roll5to5

roll@ manufacturing processes in which the sustrate and deposited material move through the

production process as one continuous strip passing over several rolls in the process whichmaintain staility to the process as well as moving the product along its way.

-morphous silicon films are faricated using plasma vapor deposition techni,ues to apply silane

(Si"E) to the sustrate or other eneficial film allowing large5area solar cells to e faricated

much more easily than with conventional c5Si. Three amorphous silicon layers M p5layer i5layer and n5layer M are formed consecutively on the sustrate. This p5i5n 8unction corresponds

to the p?n 8unction of a c5Si solar cell. -morphous silicon can e deposited onto a many

sustrates Including glass and ceramics metals such as stainless steel and plastics.

Lo* temperat+re in!+ce! crystallization of amorpho+s silicon:

-morphous silicon can e transformed to crystalline silicon using well5understood and widely

implemented high5temperature annealing processes. This typical method is the typical method

used in industry ut re,uires high5temperature compatile materials such as special hightemperature glass that is e:pensive to produce. "owever there are many applications for which

this is an inherently unattractive production method. /le:ile solar cells have een a topic of

interest for less conspicuous5integrated power generation than solar power farms. These modulesmay e placed in areas where traditional cells would not e feasile such as wrapped around a

telephone pole or cell phone tower. In this application a photovoltaic material may e applied to

a fle:ile sustrate often a polymer. Such sustrates cannot survive the high temperatures

e:perienced during traditional annealing. Instead novel methods of crystalliAing the siliconwithout disturing the underlying sustrate have een studied e:tensively. -luminum5induced

crystalliAation (-I#) and local laser crystalliAation are common in the literature however not

e:tensively used in industry.

In oth of these methods amorphous silicon (a5Si or a5SiC ") is grown using traditional

techni,ues such as plasma5enhanced chemical vapor deposition (P!#V*). The crystalliAationmethods diverge during post5deposition processing.

In aluminum5induced crystalliAation a thin layer of aluminum (23 nm or less) is deposited y

physical vapor deposition onto the surface of the amorphous silicon. This stack of material isthen annealed at a relatively low temperature etween 0E3F# and ;33F# in a vacuum. The

aluminum that diffuses into the amorphous silicon is elieved to weaken the hydrogen onds present allowing crystal nucleation and growth. !:periments have shown that polycrystallinesilicon with grains on the order of 3.; H 3. Nm can e produced at temperatures as low as

023F#. The volume fraction of the film that is crystalliAed is dependent on the length of the

annealing process.

-luminum5induced crystalliAation produces polycrystalline silicon with suitale crystallographic

and electronic properties that make it a candidate for producing polycrystalline thin films for


25/42

photovoltaics. -I# can e used to generate crystalline silicon $an wires and other nano5scale

structures.

-nother method of achieving the same result is the use of a laser to heat the silicon locally

without heating the underlying sustrate eyond some upper temperature limit. -n e:cimer laser or alternatively green lasers such as a fre,uency5douled $dC-' laser is used to heat the

amorphous silicon supplying energy necessary to nucleate grain growth. The laser fluence must

e carefully controlled in order to induce crystalliAation without causing widespread melting.#rystalliAation of the film occurs as a very small portion of the silicon film is melted and allowed

to cool. Ideally the laser should melt the silicon film through its entire thickness ut not damage

the sustrate. Toward this end a layer of silicon dio:ide is sometimes added to act as a thermal arrier. This allows the use of sustrates that cannot e e:posed to the high temperatures of

standard annealing polymers for instance. Polymer5acked solar cells are of interest for

seamlessly integrated power production schemes that involve placing photovoltaics on everyday

surfaces.

- third method for crystalliAing amorphous silicon is the use of thermal plasma 8et. This strategy

is an attempt to alleviate some of the prolems associated with laser processing H namely thesmall region of crystalliAation and the high cost of the process on a production scale. The plasma

torch is a simple piece of e,uipment that is used to thermally anneal the amorphous silicon.

#ompared to the laser method this techni,ue is simpler and more cost effective.

Plasma torch annealing is attracti'e because the process parameters and

e$uipment dimension can be changed easily to yield 'arying le'els of performance.

A high le'el of crystalli1ation (tilt andle/ should be cleaned more often, as they will not self-clean as effectively as %olar 0anelmounted at a ()>tilt or greater.

9t is advisable to perform periodic inspection of the %olar 0anel for damage to glass, backskin, frameand support structure. 6heck electrical connections for loose connections and corrosion. 6heck if mounting support structure and modules are loose. 6heck connections of cables, connectors, and

grounding. 6hange %olar 0anel must be the same kind and type, if need. %olar 0anel can operateeffectively without ever being washed, although removal of dirt from the front glass can increaseoutput. The glass can be washed with a wet sponge or cloth, wear rubber gloves for electricalinsulation.


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Solar Panel Safety precautions

%olar 0anel installation and operation should be performed by &ualified personnel only. 6hildren shouldnot be allowed near the solar electric installation.

Avoid electrical ha7ards when installing, wiring, operating and maintaining the module. %olar 0anelproduce 56 electricity when e!posed to light and therefore can produce an electrical shock or burn.%olar 0anel produce voltage even when not connected to an electrical circuit or load. %olar 0anelproduce nearly full voltage when e!posed to as little as )? of full sunlight and both current and powerincrease with light intensity. 5o not touch live parts of cables and connectors. As an added precaution,use insulated tools and rubber gloves when working with %olar 0anel in sunlight.

all of %olar 0anel from high place will cause death, in#ury or damage. 5o not drop %olar 0anel or allowob#ects to fall on %olar 0anel, never leave a %olar 0anel unsupported or unsecured. 9f a module shouldfail, the glass can break a %olar 0anel with broken glass cannot be repaired and must not be used.

$hen installing or working with %olar 0anel or wiring, cover module face completely with opa&ue

material to halt production of electricity. %olar 0anel have no on8off switch. %olar 0anel when e!posedto sunlight generate high voltage and are dangerous, %olar 0anel can be rendered inoperative only byremoving them from sunlight, or by fully covering the front surface with opa&ue cloth, cardboard, orother completely opa&ue material, or by working with %olar 0anel face down on a smooth, flat surfacewhen installing or maintaining.

5o not artificially concentrate sunlight on the %olar 0anel.

%olar 0anel can produce higher output than the rated specifications. 9ndustry standard ratings are made at conditions of (+++$8 and *)Qcell temperature. Reflection from snow or water can increase sunlight and therefore boost current and power. 9n addition, coldertemperatures can substantially increase voltage and power.

%olar 0anel are intended for use in terrestrial applications only, thus e!cluding aerospace or maritimeconditions or use with sunlight concentration.

9t is recommended that the %olar 0anel remains packed in the bo! until time of installation.

$ork only under dry conditions, with a dry %olar 0anel and tools, since sparks may be produced, do notinstall %olar 0anel where flammable gases or vapors are present.

5o not drill holes into %olar 0anel frame as it will void warranty. %olar 0anel ate constructed frame as itwill void warranty.


27/42

@andled with care, if the front glass is broken or if the polymer backskin is tom, contact with anymodule surface or the frame can produce electrical shock. 0articularly when the %olar 0anel is wet,broken or damaged modules must be disposed of properly. 5o not disassemble, bend, impact by sharpob#ects, walk on, and throw or drop etc. keep back surface free from foreign ob#ects. Avoid sharpedges.

Use %olar 0anel for its intended function only follows all %olar 0anel manufacturers' instructions. 5o notdisassemble the module, or remove any part or label installed by the manufacturer. 5o not treat theback of the %olar 0anel with paint or adhesives.

9f not otherwise specified, it is recommended that re&uirements of the latest local, national or regionalelectrical codes be followed.

Retain this installation manual for future reference.

otes

The electrical characteristics are within ) percent of the indicated values of 9sc, 3oc, and 0ma! under standard test

conditions irradiance of (++m$8 *, A4 (.) spectrum, and a cell temperature of *)QBB>/.

_Under normal conditions, a photovoltaic %olar 0anel is likely to e!perience conditions that producemore current and8or voltage than reported at standard test conditions. Accordingly, the values of 9scand 3oc marked on this module should be multiplied by a factor of (.*) when determining componentvoltage ratings, conductor ampacities, fuse si7es, and si7e of controls connected to the 03 output.

How to install and wire Solar panel?

Solar panels can lower your energy costs and are rather easily installed, with a little construction andelectrical knowledge. @ere's how to do it.

%olar panels will be the aspect of the solar power product that in fact gathers the power from your sun.

The panels are developed up of photovoltaic tissue that transform thesun's power to immediate e!isting powerthat is often applied for heating system orto energy appliances. The power is thensent straight to an appliance or otherdevice, or is saved inside a power supplylender for long term use. 0anels commonlymeasure around (.) ft by three feet, andcan provide about B) watts of power if situated in total sun.

Typically the panels are installed around

the roof of the building. @owever, they isoften installed over a stand-alone rack if necessary. one of the most crucial thing toconsider is #ust how much sunshine thepanel are certain to get while in the area

you choose. %olar panels drop effectiveness easily in even a partially shaded location, so go with a areathat receives total sunshine for as prolonged as achievable each and every day. The panels ought to beoriented for the to the south if whatsoever possible. The *nd most effective preference would be todeal with the panels for the west or east, but you are heading to have to take advantage of additionalpanels in purchase to ac&uire identical level of energy. never ever deal with the panels for the north.


28/42

"e positive to ac&uire any important setting up permits #ust before setting up the panels. e!aminetogether with your community setting up or 7oning department to locate out what are the needs arewith your community. if you occur to don't have the permits #ust before the set up or don't total theset up in accordance with community setting up codes, you may likely be forced to tear out all of yourvery hard operate and commence again.

The panels ought to be tilted to attain the optimum level of sun. The stage of tilt is dependent aroundthe latitude at which they may be installed. 0anels set up at + to () degrees latitude really should havea very ()-degree tilt. 0anels set up at () to twenty five degrees latitude really should have a very tiltthat could be the very same since the latitude. or each and every supplemental ) degrees of latitudeas much as C+ degrees, include an added five degrees of tilt for the latitude. At latitudes of C+ degreesand above, include twenty degrees of tilt for the latitude. 4ounts ought to be inserted about CD inchesaside and ought to be situated straight on ma#or of the rafter, if whatsoever possible. 9f a rafter #ustisn't accessible with the mount site, the mount is often connected to some prevent of wooden insertedaround the underside for this roof. don't attach the mount straight for the plywood sheathing for thisroof. locate rafters using a stud finder. preserve the mounts inside a right line, utili7ing a laser beamsight or probably a chalk line. 5rill a hole using a pilot little bit to insure that which you don'tseparation the rafter. Then protected the bottom for this mounts for the roof, utili7ing stainless metallag bolts. Thread the submit for this mount into its base. make positive to spot roof flashing throughouteach and every mount to avoid leaks while in the roof. up coming fasten steel rails for the mounts withstainless metal bolts. total the racking product by connecting aluminum solar racks for the steel rails.4ake positive how the finished rack product will grant the solar panels being no much less than E to Finches away the roof. The panels will run additional effectively if there's sufficient airflow below andclose to them.

%olar panels may likely be preassembled in groups. This can make the set up less complicated and&uicker, as there are actually much less person models to cope with up around the roof. protected thesolar panels for the racking product while using restraining hardware provided while using panels. eachand every maker has their individual hardware, particularly constructed for his or her individual panels.analy7e the panels to produce positive that they may be anchored securely. 4ake positive how thetogether the solar panel and also the racking methods are effectively grounded in accordance whileusing community electric codes.

9nterconnect the solar panels by starting the #unction penalty area around the back again of each andevery panel and attaching the wires for the correct good and unfavorable terminal screws while in thebo!, getting clear of one-half inch of insulation from your finishes for this wires first. The wire willoperate involving panels as a result of the knockouts in each and every bo!. operate the wire from yourlast panel to some distinct array #unction bo!. The wire is then operate as a result of electric conduitfor the up coming electric aspect for this system, this type of since the cost controller. near all#unction bo!es.


29/42

called the crystal material, represent the natural shape of a regular polyhedron, with obvious edgesand corners with the plane, the atom is in accordance with its internal law must line up neatly, sowhen they break off the plane according to certain, such as salt, crystal and so on.

*. 5ifference between monocrystallie and polycrystallineG %ome of the crystal is composed of manysmall grains, if the arrangement between the grains are no rules, this is called polycrystalline crystal,

such as copper and iron. "ut there are also the crystal itself is a complete large grains, the crystal iscalled single crystal, crystal and crystal diamond.

E. 4onocrystalline silicon and polycrystalline silicon photovoltaic cells compareG 4onocrystallinesilicon cells with a cell conversion efficiency, good stability, but the cost is high. Low-costpolycrystalline silicon cells, the conversion efficiency slightly lower than the 67ochralski silicon solarcells and materials in a variety of defects such as grain boundaries, dislocations, micro-defects, andmaterial impurities carbon and o!ygen, as well as the stained process transition metals.

The first is the advent of solar cell silicon solar cells. %ilicon is very abundant on the earth, an elementalmost everywhere have the presence of silicon can be said to be used without silicon to make solarcells, indeed no shortage of raw materials. "ut it is not easy to e!tract, so people in the production of monocrystalline silicon solar cells, they also studied the polycrystalline silicon solar cells and

amorphous silicon solar cells, has commercial-scale production of solar panel, also did not #ump out of silicon series. 9n fact, the semiconductor materials for manufacture of solar cells a lot, along with thedevelopment of industrial materials, solar cells will be more and more varieties. Research and trialproduction has been the solar cell, in addition to silicon series, there are cadmium sulfide, galliumarsenide, copper indium selenium and many other types of solar cells, too numerous to mention, thefollowing are a few of the more common solar cells.

4onocrystalline silicon solar cells

4onocrystalline silicon solar cells is currently the fastest developing a solar cell, its composition andproduction technology has been finali7ed, the products have been widely used for space and groundfacilities. The high purity single crystal silicon solar cells as the raw material rod, HH.HHH? purity. 9norder to reduce production costs, and now solar terrestrial applications such as the use of solar-grade


30/42

silicon rods, material performance has been rela!ed. %ome semiconductor devices can also be used forprocessing materials and discard ends of silicon materials, solar cells made by re-drawing a dedicatedsilicon rods. The slice of silicon rods, generally +.E mm thick slices. $afer after forming, polishing,cleaning and other processes, made of silicon raw material to be processed. %olar cell processing chip,the first doping and diffusion in silicon, usually for the small amount of boron dopant, phosphorus,antimony and so on. 5iffusion is the control into the &uart7 furnace for high temperature diffusion. Andthen using screen printing will be printed with a good paste made of silicon gate line, after sintering,also made of the back electrode and a gate line in the face of anti-reflection coating source, toprevent a large number of photons reflected from a smooth silicon surface, thus, single-chip siliconsolar cells are produced. After single-chip random testing, according to the re&uired specifications canbe assembled into solar modules solar panels/, the method used in series and parallel to a certainoutput voltage and current, and finally with the framework and package materials package. Accordingto the system user can design different si7e solar module solar cell composed of a variety of s&uare,also known as the solar array. 6urrent silicon photoelectric conversion efficiency of solar cells is about()?, laboratory results have more than *+?. Also for the space station up to )+? or more solar panels.

0olycrystalline silicon solar cells

4onocrystalline silicon solar cell production re&uires large amounts of high-purity silicon material, the

production of these materials, process comple!ity, power consumption drastically, the total cost of solar cell production has been over half, combined with the silicon rod was drawn cylindrical, slicedwafer production solar cells is to form a solar module surface low utili7ation rate. Thus, D+ years, someIuropean and American countries, the development into a polycrystalline silicon solar cells.0olycrystalline silicon solar cells using current materials, mostly a collection contains a lot of singlecrystal particles, or silicon materials from waste materials and metallurgical grade silicon melt molded.The process is to select a resistivity of (++ to E++ ohmsG 6m block of material or a polycrystallinesilicon material end to end, after crushing, with the (;) mi!ture of hydrofluoric acid and nitric acidcorrosion appropriate, and then spent neutral-ioni7ed water rinse and drying. Juart7 crucible installedpolysilicon materials, the addition of appropriate amount of boron in silicon, release the castingfurnace, heating and melting in a vacuum state. 4elted insulation should be about *+ minutes, andthen in#ected into the graphite mold, to be cooled slowly solidified, that have polysilicon ingot. Theingots can be cast cubes to be processed into s&uare slices film solar cells can improve materialutili7ation and easy assembly. 0olycrystalline silicon solar cells and solar cell production process is

similar to the photoelectric conversion efficiency of about (*?, slightly lower than the silicon solarcells, but the material is simple, to save power consumption, the total production costs low, so get alot of development. As the technology was improved, the current conversion efficiency of polycrystalline silicon can also be reached around (C?.

Amorphous silicon solar cells

Amorphous silicon solar cells appeared in (HBF with a new thin film solar cells, monocrystalline andpolycrystalline silicon solar cells it with the production method is completely different, very littlesilicon material consumption, lower power consumption, very attractive. 4ethod of manufacturing avariety of amorphous silicon solar cells, the most common is the glow discharge method, as well asreactive sputtering, chemical vapor deposition, electron beam evaporation and thermal decompositionof silane method. Klow discharge method is a 5an


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undoped i layer, and then deposited a layer of 0-type boron-doped amorphous silicon, and finally alayer of electron beam evaporation of antireflection coatings, and deposition of silver electrodes. Thisproduction process, a series of deposition chamber can be used in production form a continuousprocess to achieve mass production. 4eanwhile, the thin amorphous silicon solar cells can be made intolaminated type, or use to manufacture integrated circuits in a plane, with the appropriate masktechnology, a production of multiple batteries in series to obtain higher voltage . "ecause the average

crystalline silicon solar cells around a single voltage of +.) volts, and now the production of amorphoussilicon tandem solar cells in apan up to *.C volts. The current problem is that of amorphous siliconsolar cell conversion efficiency is low, the international advanced level of about (+?, and is not stableenough, often decline down conversion efficiency of the phenomenon, so not a lot of use for large-scale solar power, but mostly with in low light power, such as pocket electronic calculators, electronicwatches and clocks and copier and so on. ailure to overcome the drop in efficiency issues, theamorphous silicon solar cells will promote the great development of solar energy, because its low cost,light weight, easier application, it can be combined with the housing of the roof form independentpower of households.

9n the fierce sun, single crystal solar panels can be transformed more and more non-crystal-type solarenergy to electricity more than doubled, but unfortunately, the price of single crystal type of non-crystal-like than the two or three times more e!pensive, and in the case of non-cloudy 9nstead, the

crystal-type transistor can be almost as much to collect solar energy.

Solar Panel Mountin

or home solar arrays, we generally recommend mounting solar panels at the top of a sturdy pole. Thisis called a pole top mount. They are easy to install. They keep the panels off the ground and out of harm's way but are easy to ad#ust and to reach for snow removal.


32/42

A pole top mount can be either fi!ed, which means it holds the panel stationary, or it can move, ortrack, with the sun. A solar panel mount that allows the panel to move with the sun is called a tracker.i!ed Racks can include !round Mountin" #oof Mountin" Pole-Side Mountin" $oat%#& Mounts , aswell as Pole 'op Mountin. All trackers are mounted on poles, and so are technically pole top mounts.

The pole of a pole top mount must be anchored in the ground by digging a hole and filling it with

concrete. The si7e of hole in diameter is usually (D inches to * feet (D inches plus the diameter of thepole/. The depth of the hole must be (8* of the height of the pole above ground. 9f the pole will be Bfeet above ground, you have to dig a E (8* foot hole.

The placement of your solar panels, whatever kind of mounting system you are using, can make a hugedifference in the amount of electricity you are able to produce. "e very careful not to place yourpanels in an area that is shaded by trees or buildings or any other ob#ect. ote carefully that theshadow made by your house moves at least ** feet farther to the south in the winter. 9f you place yourpanels within that distance, you'll be very disappointed during those short winter days.

$e have three types solar panel mounting;

Pitch #oof mountin look neat, but are hard to reach to ad#ust the angle. $ill you want to walk across

your roof several times a year to ad#ust the angleG 5oes it snow oftenG $ill you have to walk across aslippery roof to sweep snow off the panelsG 9s the slope of the roof you want to use good for optimumsolar panel efficiency or will you need tilt legs to face your panels more perpendicular to the sunG

Pole Mountin are designed to hold ( to C modules and are mounted to the pole with either hoseclamps or U-bolts not provided/. The racks accommodate different si7ed poles and are ad#ustable foroptimal sun angle from () to F) degrees in (+-degree increments. 0ole si7e is determined by thenumber of modules to be mounted.

!round Mountin are probably the easiest way to mount solar panels. This mount resembles an A-frame. 9t safest to attach this structure to a cement slab so that it may be secured in place. Kroundmounts are designed to handle from ( to D solar modules. Kround mounts can be used to attach solarpanels to the ground, to a roof and or to a vertical surface. %ome ground mounts have tiltable, orad#ustable legsM others are fi!ed. 2ptional ad#ustable tilt legs are available for several of the styles of panels $holesale %olar sells.

: Pitch roof solar mountin

Rooftop_ solar mounting system apply for all kinds of pitch roof of any building. %olar panel can fastened

onto the top flute of our patented solar mounting rail. L-feet connects with the bottom of the rail, which mounted

firmly to the roof. 9nstall flashing over a layer of shingles to insure water resistance. A single wrench is enough for

the installation procedures. 5etailed installation manual ensure an easy and smooth installation.


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Specification:

• 5esign $ind Load; ))m8s or *++km8hour

• 5esign %now Load; (.)kn8m*• %teel structure; Anodi7ed Aluminum N %tainless %teel

• reference standard; A%8O ((B+.*

• 9nstallation site;0itch root

• Kuarantee; Ten years guarantee on parts

(.$e use L-feet for tin roof and hook for tile-roof to connect the rack structure with the rafters of theroof.

*.At the installation site we do not re&uire welding, and even have no need to drill a hole, #ust usingthe electrical locks and wrenches and other simple tools to complete the installation. This simplify thetraditional installation procedure, we will manage to preassemble the screws and nuts before shipmentto reduce on-site installation procedures and labor intensity. Iliminate the differences in degree of on-site professional installation and degree of impact on the &uality of the roof support system.

E.Utili7ation of the anodi7ed aluminum, stainless steel, anti-aging U3 process to ensure the longer lifespan of our solar technology and solar tracking.

_: !round Solar Panel Mountin:

Kround %olar 0anel 4ounting is suitable for flat roofs of various structures or for the ground. 2ne endof the cross-beam is connected firmly with the ground structure by base bracket and he!-bolts and theanother end is connected to the support leg forming a stable and strong tripod structure. Theconnecting foot is made up of stainless steel to enhance the load bearing capacity. %tainless steel itself has a good physical and chemical mechanical performance, service life can reach more than E+ years.


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Specification:

5esign $ind Load ))m8s or *++km8hour

5esign %now Load (.)kn8m*

%teel structure; Anodi7ed Aluminum N %tainless %teelReference standard; A%8O ((B+.*9nstallation site; lat roop or KroundKuarantee; Ten years guarantee on parts

_ : Pole Solar Panel Mountin

0ole system is designed for up to (.)kw panel mounting system, with the wind load up to *++km8h.This panel mounting system is suited for large photovoltaic system installation in all wind 7ones. Thissolar mounting system can ad#ust the tilt angle according to the re&uirement of the installation place.There is no need to welding in the complete installation process. According to our manual instruction,you can install the solar modules easily, &uickly, securely and cost efficiently.


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Specification:

5esign $ind Load ))m8s

5esign %now Load (.)kn8m*

%teel structure @ot dipped galvani7ed steel N Anodi7ed Aluminum

Reference standard A%8O ((B+.*

Tracker type i!ed

Tilt angle +>P F+>Kuarantee Ten years guarantee on parts

(. 6onvenient___and_

&uick_ installation. The use of bolted connections eliminates drilling and welding

process automatically reducing the operating time.

*. 4ounting rack structure uses hot dip galvani7ed steel parts which gives a good e!ternalappearancesilvery white/ and also has good corrosion resistance.Under natural conditions, it can beused for *+-E+ years.


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E. "atteries components are made up of aluminum alloy treated with anode o!idation process whichmakes the appearance of smooth and bright. %ince this material is same as panel frame, it candecrease metal corrosion phenomena mutually.

C @olding component bolts ,screws/ are made of stainless steel bolts, stainless steel itself has a good

physical and chemical mechanical properties, its service life span can reach more than E+ years.

!round Solar Panel Mountin System

Kround Solar Panel Mountin %ystem or %afe9nstallation $ork

This manual contains critical information regardingelectrical and mechanical installation and safety

information which you should know before startinginstallation.

6AUT92% RIKAR59K 9%TALLAT92 2KRA6I%2LAR

O%top working duringunder storms, typhoons,hurricanes, earth&uakes, volcanic eruptionsand other adverse weather and natural disaster

situations.Oever step or sit on the glass surface of a solar module. The glass may break, resulting in shock orbodily in#ury. The module may also stop generating power.O0lease strictly abide by height safety regulation in high-attitude operation

O0lease strictly abide by live working safety norms in line operationO0lease strictly abide by heat work safety regulation in heat work operationOAlways use the specified tools. The solar modules or mounts may fall if the installation is notstrong enough, for e!ample when parts are not tightened sufficiently.O0lease strictly in accordance with the re&uirements of this manual for installation.

O9nstallation %tepsOi! the pole as demonstrated. 9nstall the main beam by QE+ 0in. 9nstall the ad#ustable part byQ*+pin0icture C/ 2ne end attached to pole, the other end attached to main beam.

O0lace the supporting beam on the main beam, fi! it with 4D he! screws.

O9nstall the C+C+ con#unctions. $ith 4D screw go in through the hole on the supporting beam. 9nstallall the con#unctions in this way. eep all the con#unction face one side

O0lace the rails on the supporting beam. The rail is attached to the con#unction.

ote Rails connected by splice kit.

O0lace the first module of the bottom row. %lide the end clamp tightly against the solar panel andfasten it.


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ote The rail should leave a space of *)mm-E+mm

O%lide the ne!t module against the installed module_.asten the mid clamp. 9nstall other modules and

clamps in this way. eep module even.

The angel could be ad#ustable by the ad#ustable parts by changing its position to the main beam.

Pole 'op Solar Panel Mountin System

0ole Top Solar Panel Mountin %ystem

This manual contains critical informationregarding electrical and mechanical installationand safety information which you should knowbefore starting installation.


O%top work during stormy weather. %olarmodules can be caught in the wind, causingyou to fall.Oever step or sit on the glass surface of

a solar panel. The glass may break, resulting in shock or bodily in#ury. The module may also stopgenerating power.OAlways use the supplied parts to attach the solar modules and mounts. Use of weaker parts, suchas screws that are too short, is dangerous and may cause the solar modules or mounts to fall.OAlways use the specified tools. The solar modules or mounts may fall if the installation is not

strong enough, for e!ample when parts are not tightened sufficiently.O5o not modify or cut parts. 5oing so is dangerous. %afety cannot be guaranteed.O0roduct should be installed and maintained by &ualified personnel. eep unauthori7ed personnelaway from solar modules

9nstallation %teps

O5etermine the position of leg positions in the beginning.

OThe distance between each leg pair L( e&uals to the length of %upporting 0ipe

O9nstallation of the angle iron onto the legs.

O0ut %upporting 0ipe onto the front leg8rear leg, i!ed it with U-bolts.

Oirstly put rails on the supporting pipe.

Oote; the position of the rails.

O 9nstallation of the splice to connect multiple rails together. %lide the splice on the rear side of the


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pre-assembled rails. asten the first bolt firmly. Then slide the ne!t rail into the splice.

O9nstallation of the rails. i! the rail with U bolt kit.

O9nstall all the rails onto the supporting pipe.

O0lace the first module of the bottom row. %lide the end clamp tightly against the module and fastenit. 9nstall the end clamp and mid clamps.


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O9nstall all the panels. inished.

Pitched #oof #ac(in Solar Panel Mountin System )nstallation Manual

or %afe 0itched Roof Racking Solar Panel Mountin %ystem 9nstallation $ork

This manual contains critical informationregarding electrical and mechanicalinstallation and safety information whichyou should know before startinginstallation.


O%top work during stormy weather. Solarpanel can be caught in the wind, causingyou to fall.Oever step or sit on the glass surface of a solar module. The glass may break,resulting in shock or bodily in#ury. The

module may also stop generating power.OAlways use the supplied parts to attach the solar modules and mounts. Use of weaker parts, suchas screws that are too short, is dangerous and may cause the solar modules or mounts to fall.OAlways use the specified tools. The solar modules or mounts may fall if the installation is not

strong enough, for e!ample when parts are not tightened sufficiently.O5o not modify or cut parts. 5oing so is dangerous. %afety cannot be guaranteed.O0roduct should be installed and maintained by &ualified personnel. eep unauthori7ed personnelaway from solar modules

029T% T2 6@I6

O5etermine the wind loads for the installation site. 6heck with your local building and safetydepartment for the specific re&uirements. 4ake certain that the roof structure can support thelive and dead loads resulting from the installation of the 03 array.O9nstall solar modules facing south, if possible. 9nstallations facing east and west are also possible,although the amount of power generated will be lower.

9nstallation %teps

O5etermine the position of the roof hooks according to your design.

OThe roof hook must not press against the roof tile. 0lace it flat. 9f necessary, shim the roof hook withwood.

9f necessary, use an angle grinder or hammer to cut a concavity in the tile that covers the roof hook atthe point where the roof hook comes through. 6aution 4ust not use fi!ed roof hook as a ladder, as

O9nstallation of the clamps

OThe edge of solar panel to the rail distance; *)mm-E+mm


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this e!treme point load could damage the tile below.

O9nstallation of the rails on roof hooks.


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9nstallation of the splice to connect multiple rails together. %lide the splice on the rear side of the pre-assembled rails. asten the first bolt firmly. Then slide the ne!t rail into the splice. $hen comestogether, fasten the other bolt. The connection is finished. An e!pansion gap at the rail #oints issuggested. Leave a gap about a finger width.

O0lace the first module of the bottom row. %lide the end clamp tightly against the module and fasten

it. 9nstall the end clamp and mid clamps.

O6lamp 9nstallation

O%lide the ne!t module against the installed module. asten the mid clamp. 9nstall other modulesand clamps in this way. eep module even.

9n 2ur 0ro#ect $e connect 0anel in both series and parallel.


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study of solar panel and power generation

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