solar pv plant quality assurance checkpoints v2

A report by Firstgreen Consulting Pvt Ltd

Solar PV Module Quality Assessment

List of Figure- ................................

List of Table- ................................

List of Graph- ................................

1. Check points and parameter on input side that is raw material with quality

checks and testing procedures:

a. It is import that the PV module is made of glass with anti reflective (ARC) coating (ARC):

b. Ensure that PV modules are free with the TCO corrosion:

c. Ensure the quality of EVA sheet:

d. Ensure that the Junction Box is of good quality:

e. Ensure that the Back sheet should have the UV protection and moisture protection

features: ................................................................

f. Front glass should have a very high transmitivity feature:

g. EVA Gel Content should be over 67%:

h. It is preferred to have a 3 Bus

2. Check points on manufacturing process and customer hold points

a. Wafer processing technology affect the PV module quality:

b. It is important the wafers used for cell manufacturing have high surface roughness:

c. Ensure that the manufacturer conducts Wet Leakage current test

d. Ensure that manufacturer has online facility to conduct the Photoluminescence

spectroscopy: ................................

e. Ensure that manufacturer has Thermal imaging cameras in it production process:

f. Production Technology of PV modules:

3. Check points and parameters on final product

a. Ensure that the Manufacturer conducted the Electro Luminescence (EL) Testing on each

module rather than on a sample size:

b. Module Tolerance should be minimum:

c. Ensure that the PV modules are PID Free PV Modules:

4. How to ensure that the Supplier is supplying the material which was tested and is

as per specification- ................................

Table of Content

................................................................................................................................

................................................................................................................................

................................................................................................................................

Check points and parameter on input side that is raw material with quality

checks and testing procedures:................................................................................................

It is import that the PV module is made of glass with anti reflective (ARC) coating (ARC):

Ensure that PV modules are free with the TCO corrosion: ................................

Ensure the quality of EVA sheet: ..........................................................................................

he Junction Box is of good quality: ................................................................

Ensure that the Back sheet should have the UV protection and moisture protection

................................................................................................

Front glass should have a very high transmitivity feature:................................

EVA Gel Content should be over 67%: ................................................................

It is preferred to have a 3 Bus-bar design: ................................................................

Check points on manufacturing process and customer hold points- ...........................

Wafer processing technology affect the PV module quality: ................................

It is important the wafers used for cell manufacturing have high surface roughness:

Ensure that the manufacturer conducts Wet Leakage current test ................................

Ensure that manufacturer has online facility to conduct the Photoluminescence

............................................................................................................................

Ensure that manufacturer has Thermal imaging cameras in it production process:

Production Technology of PV modules: ................................................................

Check points and parameters on final product- ................................................................

nsure that the Manufacturer conducted the Electro Luminescence (EL) Testing on each

module rather than on a sample size: ................................................................

odule Tolerance should be minimum: ................................................................

Ensure that the PV modules are PID Free PV Modules: ................................


...........................................................................................................................

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It is import that the PV module is made of glass with anti reflective (ARC) coating (ARC): 6

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Ensure that the Back sheet should have the UV protection and moisture protection

...................................... 8

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It is important the wafers used for cell manufacturing have high surface roughness: ..... 10

.................................. 10

Ensure that manufacturer has online facility to conduct the Photoluminescence

............................ 10

Ensure that manufacturer has Thermal imaging cameras in it production process: ........ 11

............................................. 11

.................................. 12

nsure that the Manufacturer conducted the Electro Luminescence (EL) Testing on each

...................................................... 12

............................................ 12

..................................................... 13


........................... 14

Ensure that the supplier company is certified by international certifications and fulfilling the

standards ................................

Conduct a manual check that when

quoted specification on the product.

Photovoltaic (PV) module factory insp

Ensure that the manufacturer is doing the following tests:

A general overview of the standard/certificates/codes for PV modules and its components

5. What are the performance guarantee tests after commissioning and methods to

ensure that vendor will ensure compliance

Plant layout evaluation– ................................

SCADA System Inspection– ................................

Mounting and Structure Inspection

PV Module and Array Inspection

Inverter Commissioning review

Grid Sub Station (GSS) Inspection

6. What are the performance bank guarantees taken from the suppliers and for how

many years- ................................

Defects liability guarantee from the Suppliers:

Warrantees from the PV Module Manufacturers are for 25 years

c) Linear performance guarantee:

7. How to ensure that the module is in line with SECI standards requirement (IEC

61215, IEC 61730 and IEC 61701)

8. How to ensure peak output wattage is more than 90 % in first ten years and more

than 80 % at the end of 25th year

a) Service certificate: ................................

b) Degradation factor/rate: ................................

c) Power Tolerance: ................................

Construction and Maintenance Practices

................................................................

Some Typical PV modules Field Failures

Examples of Field Failures ................................

supplier company is certified by international certifications and fulfilling the

................................................................................................................................

when the material was procured and comparing it with the

quoted specification on the product. ........................................................................................

Photovoltaic (PV) module factory inspection -................................................................

Ensure that the manufacturer is doing the following tests: ................................

A general overview of the standard/certificates/codes for PV modules and its components


ensure that vendor will ensure compliance ................................................................

................................................................................................

................................................................................................

Mounting and Structure Inspection- .........................................................................................

PV Module and Array Inspection– ............................................................................................

Inverter Commissioning review – ..............................................................................................

) Inspection- ............................................................................................


................................................................................................................................

Defects liability guarantee from the Suppliers: ................................................................

Warrantees from the PV Module Manufacturers are for 25 years ................................

Linear performance guarantee: .........................................................................................

at the module is in line with SECI standards requirement (IEC

61215, IEC 61730 and IEC 61701)- ...............................................................................................

to ensure peak output wattage is more than 90 % in first ten years and more

than 80 % at the end of 25th year ................................................................................................

................................................................................................

................................................................................................

................................................................................................

Construction and Maintenance Practices can also help in maintaining the longer module life:

................................................................................................

Some Typical PV modules Field Failures ................................................................

................................................................................................

supplier company is certified by international certifications and fulfilling the

.................................. 14

procured and comparing it with the

........................ 14

.......................................... 15

..................................................... 15

A general overview of the standard/certificates/codes for PV modules and its components . 16


.............................................. 17

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........................................ 17

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........................................... 21

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at the module is in line with SECI standards requirement (IEC

............................... 23


................................. 25

.............................................. 25

................................... 25

............................................... 25

can also help in maintaining the longer module life:

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9. What should be the liquidated damages for non performance of the module?

a) Product warranty-Ten Years Repair, Replacement or Refund

b) Performance warranty ................................

10. What should be insurance requirement to cover loss of profit?

All risk policy, including Loss of Income and Reduced yield cover

Insured and non-insured reduced yield

Third Party Liability insurance-

Appendix ................................................................

The following tests conducted by Jinco Solar in their production process

The following tests conducted by JA Solar in their production process

The following tests conducted by


List of Figure-

Figure 1: PV Module with & without anti

Figure 2: EVA Coating ................................

Figure 3: Junction Box Connection

Figure 4: Busbar Designs ................................

Figure 5: Solar Modules under Electro Luminescence test

Figure 6: Module Dimension ................................

Figure 7: Solar PV Module under PID Test (a) Normal PV Panel (b) Degraded PV Panel

Figure 8: Standard/Certificates/Codes for PV modules and its components

Figure 9: Common PV Module Failure & Damages

Figure 10: Some Additional PV Module Failure

List of Table-

Table 1: Some of the certification standards available for solar PV components

Table 2: Overview of IEC tests ................................

List of Graph-

Graph 1: Solar Panel Warranty Comparison

at should be the liquidated damages for non performance of the module?

Ten Years Repair, Replacement or Refund ................................

................................................................................................

10. What should be insurance requirement to cover loss of profit? ................................

All risk policy, including Loss of Income and Reduced yield cover – ................................

insured reduced yield ................................................................

- ................................................................................................

................................................................................................

The following tests conducted by Jinco Solar in their production process ...............................

The following tests conducted by JA Solar in their production process ................................

The following tests conducted by C Sun in their production process ................................

The following tests conducted by Renesola in their production process ................................

Figure 1: PV Module with & without anti-reflecting coating ................................

................................................................................................

ure 3: Junction Box Connection ................................................................................................

................................................................................................

Figure 5: Solar Modules under Electro Luminescence test .........................................................

................................................................................................

Figure 7: Solar PV Module under PID Test (a) Normal PV Panel (b) Degraded PV Panel

Figure 8: Standard/Certificates/Codes for PV modules and its components ............................

Figure 9: Common PV Module Failure & Damages ................................................................

: Some Additional PV Module Failure ................................................................


................................................................................................

Graph 1: Solar Panel Warranty Comparison ................................................................................................................................

at should be the liquidated damages for non performance of the module? ....... 30

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Figure 7: Solar PV Module under PID Test (a) Normal PV Panel (b) Degraded PV Panel ........ 13

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Table 1: Some of the certification standards available for solar PV components ..................... 14

...................................... 24

..................................... 22

1. Check points and parameter on input side that is raw material with quality


Following are the key material, quality checks

affect the module quality:

a. It is import that the PV module is made of glass with a

coating (ARC): Use of ARC coating on the PV module glass reduces light

reflectance thus maximizing the light coupling to

about 4% of the incident solar radiation are reflected through a normal glass

and use of ARC coating on the PV module glass increases its generation by up

to 4%.

Figure 1: PV Module with & w

b. Ensure that PV modules are free with the TCO corrosion

should check for negative cell polarity vs. ground, Moisture ingress/ high Temperature. It is basically for Thin Film and Sodium ion glass is used to avoid TCO corrosion. To achieve maximum efficiency high resistive SiNx layers are used.



Following are the key material, quality checks and technology parameters which

affect the module quality:

It is import that the PV module is made of glass with anti r

Use of ARC coating on the PV module glass reduces light

reflectance thus maximizing the light coupling to the solar cells. Typically



: PV Module with & without anti-reflecting coating

Ensure that PV modules are free with the TCO corrosion

should check for negative cell polarity vs. ground, Moisture ingress/ high Temperature. It is basically for Thin Film and Sodium ion glass is used to

CO corrosion. To achieve maximum efficiency high resistive SiNx


and technology parameters which

reflective (ARC)

Use of ARC coating on the PV module glass reduces light

the solar cells. Typically



Ensure that PV modules are free with the TCO corrosion: In this we should check for negative cell polarity vs. ground, Moisture ingress/ high Temperature. It is basically for Thin Film and Sodium ion glass is used to

CO corrosion. To achieve maximum efficiency high resistive SiNx

c. Ensure the quality of EVA sheet

Ethylene Vinyl Acetate (

studied for their water vapor

properties. WVTR, at test conditionsupto85°C/100%relative humidity (RH),

and adhesion values are measured before and after filtered xenon arc lamp

ultraviolet (UV) exposure and damp heat exposure at 85°C/85%RH. Water

ingress is quantified by weight gain and embedded humidity sensors.

d. Ensure that the Junction Box

withstand to high temperature conditions.

somewhat hotter) is achievable locally at the cell and also at operating by

diode(s).

Ensure the quality of EVA sheet: It should not allow the water ingress.

Ethylene Vinyl Acetate (EVA) and an encapsulant replacement for EVA are

studied for their water vapor transmission rate (WVTR) and adhesion




ngress is quantified by weight gain and embedded humidity sensors.

Figure 2: EVA Coating

Junction Box is of good quality: The junction box should

withstand to high temperature conditions. The temperature of 150°C (or even

somewhat hotter) is achievable locally at the cell and also at operating by

It should not allow the water ingress.

replacement for EVA are

WVTR) and adhesion




ngress is quantified by weight gain and embedded humidity sensors.

The junction box should

of 150°C (or even

somewhat hotter) is achievable locally at the cell and also at operating by-pass

e. Ensure that the

protection features:

moisture protection, electrical insulation, and some degree of durability.

Technology advances, coupled with changes in IEC standards, increased back

sheet requirements. Electrical insulation performa

1000 VDC partial discharge, which meant a minimum back

~300 um. Today, it is common for manufacturers to test beyond the 1000

hour damp heat requirement, thereby placing greater importance on the

durability of laminating adhesives. As the current demand for back

increased, the need for lower cost / higher durability options has intensified.

f. Front glass should have a very high transmitivity feature

PV modules as a layer of protection a

technology glass also serves as the substrate upon which the PV material and

other chemicals are deposited. For a crystalline silicon module the glass

should have transmission > 91.4%, for amorphous silicon it should be 89

float glass.

Figure 3: Junction Box Connection

Ensure that the Back sheet should have the UV protection and moisture

tures: The role of the back-sheet is to provide UV and


Technology advances, coupled with changes in IEC standards, increased back

sheet requirements. Electrical insulation performance was mandated to pass

1000 VDC partial discharge, which meant a minimum back-sheet thickness of



nating adhesives. As the current demand for back


should have a very high transmitivity feature:

PV modules as a layer of protection against the elements. In Thin film



should have transmission > 91.4%, for amorphous silicon it should be 89

should have the UV protection and moisture

o provide UV and


Technology advances, coupled with changes in IEC standards, increased back-

nce was mandated to pass

sheet thickness of



nating adhesives. As the current demand for back-sheets has


: Glass is used in

gainst the elements. In Thin film



should have transmission > 91.4%, for amorphous silicon it should be 89% of

g. EVA Gel Content should be over 67%:

extraction in THF (Tetra

Pass Criteria:

• Good > 67%

• Critical < 67%

• Fail < 20%

(too fast processing) o

h. It is preferred to have a 3

solar cells is taken by the busbar made of silver foil. A busbar on the module

surface area reduces its

module suppliers have back contact material and conduct the electricity

generated through cells through back contact and makes the cells 100%

exposure to the solar radiations. Also most of the PV module suppliers have

typically two bus bars, and some of the su

which increases the conductive area and increases the cell resistive power

losses. The 3 busbar design also reduces the

getting lost because of the finger interruptions or breaks.

EVA Gel Content should be over 67%: Gel content determination by

extraction in THF (Tetra hydrofuran).

Good > 67%

Critical < 67%

Fail < 20% low Gel contents result from too short lamination cycles

(too fast processing) or bad raw material.

It is preferred to have a 3 Bus-bar design: Typically the electricity from the


surface area reduces its exposed area to the light, hence some of the PV

le suppliers have back contact material and conduct the electricity



typically two bus bars, and some of the suppliers use the three busbar design


The 3 busbar design also reduces the chances of generated current

getting lost because of the finger interruptions or breaks.

Figure 4: Busbar Designs

Gel content determination by

low Gel contents result from too short lamination cycles

Typically the electricity from the


area to the light, hence some of the PV

le suppliers have back contact material and conduct the electricity



ppliers use the three busbar design


chances of generated current

2. Check points on manufacturing process and customer hold points

Following are the check points for the manufacturing process and customer hold

points:-

a. Wafer processing technology affect the PV module quality:

purity polysilicon material used for the fabrication of crystalline silicon solar

cells is generally made by the Siemens method.

of the key production technologies for industrial crystalline silicon PV cells,

and improvements in wafer slicing technology have resulted in a reduction in

raw wafer thickness from 370 μm to 180 μm for Sharp industrial

polycrystalline. These days some new technologies are also being used such as

quantom diodes and photon

significantly.

b. It is important the wafers used for cell manufacturing have high surface

roughness: It is desirable to have high surface roughness of PV modules.

These days texturing technology is used to maintain a surfac

wafers. Plasma technology is used in such a way that it does not smoothen the

surface as usual but produces a texture where the etch rate does not depend

on crystal orientation. This is true dry iso

regardless of wafer thickness. The surface roughness of wet

5 to 10 µm but only 0.5 to 1

roughness and topography produced by dry texturing can be controlled by the

composition of the process gas.

c. Ensure that the manufacturer conducts

leakage current test

appliances to test the electrical isolation of the housing. The test is carried out

by submersing the appliance into water with one lead attached to the electrical

leads of the appliance, and the

carried out on

for IEC61646 or IEC61625

d. Ensure that manufacturer has online facility to conduct the

Photoluminescence

used to characterize material properties of a sem

photovoltaic module. In particular, photoluminescence spectroscopy may be

used to characterize band gap, defect densities, and recombination

2. Check points on manufacturing process and customer hold points-


Wafer processing technology affect the PV module quality:


cells is generally made by the Siemens method. Wire-saw wafer slicing is one


d improvements in wafer slicing technology have resulted in a reduction in


These days some new technologies are also being used such as

quantom diodes and photon management which increases the cell efficiency

It is important the wafers used for cell manufacturing have high surface

It is desirable to have high surface roughness of PV modules.

These days texturing technology is used to maintain a surfac

. Plasma technology is used in such a way that it does not smoothen the


on crystal orientation. This is true dry iso-texturing on one side only,

wafer thickness. The surface roughness of wet-textured wafers is

µm but only 0.5 to 1 µm for dry-textured wafers. Moreover, the surface


composition of the process gas.

sure that the manufacturer conducts Wet Leakage current test

leakage current test is an electrical withstanding test carried out on

test the electrical isolation of the housing. The test is carried out


leads of the appliance, and the other lead connected to the water. It is often

arried out on photovoltaic modules in order to qualify them

IEC61625 certification.

Ensure that manufacturer has online facility to conduct the

Photoluminescence spectroscopy: Photoluminescence spectroscopy may be

used to characterize material properties of a semiconductor in a thin film




Wafer processing technology affect the PV module quality: The raw, high-


saw wafer slicing is one


d improvements in wafer slicing technology have resulted in a reduction in


These days some new technologies are also being used such as

increases the cell efficiency

It is important the wafers used for cell manufacturing have high surface

It is desirable to have high surface roughness of PV modules.

These days texturing technology is used to maintain a surface roughness on

. Plasma technology is used in such a way that it does not smoothen the


texturing on one side only,

textured wafers is

textured wafers. Moreover, the surface


Wet Leakage current test: The wet

is an electrical withstanding test carried out on electrical

test the electrical isolation of the housing. The test is carried out


to the water. It is often

modules in order to qualify them

Ensure that manufacturer has online facility to conduct the

Photoluminescence spectroscopy may be

iconductor in a thin film



mechanisms in the semiconductor. Unfortunately, existing photoluminescence

techniques are only useful when the semiconductor is at a temperature

between room temperature and absolute zero.

e. Ensure that manufacturer has

process: Quality assurance is of fundamental importance for solar panels. To

ensure that PV panels are defect free

cameras in their production process.

f. Production Technology of PV modules:

crystalline silicon solar cells with standard cell structures are in the r

18% for mono crystalline substrates and 15

new types of back-

(MWT) cells and emitter wrap through (EWT) cells have also been developed


only useful when the semiconductor is at a temperature

between room temperature and absolute zero.

Ensure that manufacturer has Thermal imaging cameras in it production

Quality assurance is of fundamental importance for solar panels. To

hat PV panels are defect free manufacturers install thermal imaging

production process.

Production Technology of PV modules: The efficiencies of typical commercial

crystalline silicon solar cells with standard cell structures are in the r

crystalline substrates and 15–17% for polycrystalline substrates

-contact polycrystalline cells, such as metal wrap through

(MWT) cells and emitter wrap through (EWT) cells have also been developed


only useful when the semiconductor is at a temperature

in it production

Quality assurance is of fundamental importance for solar panels. To

manufacturers install thermal imaging

The efficiencies of typical commercial

crystalline silicon solar cells with standard cell structures are in the range of 16–

17% for polycrystalline substrates

contact polycrystalline cells, such as metal wrap through

(MWT) cells and emitter wrap through (EWT) cells have also been developed.

3. Check points and parameters on final product

Check points for final product are

a. Ensure that the Manufacturer conduct

Testing on each module rather than on a sample size:

performed by most of the companies h

manufacturers are doing on random sampling basis, and some reputed

suppliers conduct this test on 100% of the PV modules passing through this

testing procedure. EL imaging techniques are well established and can identify

the defective modules or underperforming modules and park them separately

in a different lot. EL testing is performed just before the packing of the PV

modules in the whole process.

Figure 5: Solar Modules under Electro Luminescence tes

b. Module Tolerance

modules with a positive tolerance. Many PV module suppliers provides

modules with positive as well as negative tolerance

tolerance (10% range) or a

handle and will increase the module mismatch losses.

ts and parameters on final product-

for final product are as follows-

Ensure that the Manufacturer conducted the Electro Luminescence (EL)

Testing on each module rather than on a sample size:

performed by most of the companies however, some of the module




ctive modules or underperforming modules and park them separately


modules in the whole process.

: Solar Modules under Electro Luminescence test

Module Tolerance should be minimum: It is advisable to select the PV


modules with positive as well as negative tolerance of the range of

tolerance (10% range) or a -3%+3% (6%range) tolerance which is difficult to

handle and will increase the module mismatch losses.

Figure 6: Module Dimension

the Electro Luminescence (EL)

Testing on each module rather than on a sample size: EL testing is

owever, some of the module




ctive modules or underperforming modules and park them separately


It is advisable to select the PV


of the range of -5%+5%

ge) tolerance which is difficult to

c. Ensure that the PV modules are

Degradation is a new problem being observed

installations due to high

It is advised to select a PID free module which has been tested for the PID test

of typically a temperature of

DC and a time period of about 96 hours. Under these conditions if the module

has passed the PID test, then it can be acceptable to work satisfactory in the

Indian conditions.

(a)

Figure 7: Solar PV Module under PID Test

Ensure that the PV modules are PID Free PV Modules: Potential Induced

Degradation is a new problem being observed in the Indian PV modules

installations due to high temperature and high humidity operating conditions.


a temperature of 85 degrees Celsius, 85% relative humidity



(a) (b)

: Solar PV Module under PID Test (a) Normal PV Panel (b) Degraded PV Panel

Potential Induced

in the Indian PV modules

and high humidity operating conditions.


85 degrees Celsius, 85% relative humidity, 1000V



(a) Normal PV Panel (b) Degraded PV Panel

4. How to ensure that the Supplier is supplying the material which was

as per specification-

To ensure that the Supplier is supplying the mperfectly, there are two methods

Ensure that the supplier company is certified by international certifications and

fulfilling the standards

There Two international certification are more reliable in solar PV mare TÜV Rheinland and IECEE (IEC 61715, IEC 61730), other than of these ISO certification, CE certification, if the manufacturer is certified from them then it can be ensured for its specification and for its tests.inverters and batteries also.inspections are carried out by the certifying body to ensure ongoing compliance with the international standards.

Conduct a manual check that

with the quoted specification on the product.


Component

PV modules

Inverters

Balance of System(BoS) Combiner box Photovoltaic wire batteries

4. How to ensure that the Supplier is supplying the material which was

To ensure that the Supplier is supplying the material is as per specification and tested perfectly, there are two methods –

supplier company is certified by international certifications and

There Two international certification are more reliable in solar PV mTÜV Rheinland and IECEE (IEC 61715, IEC 61730), other than of these ISO

certification, CE certification, if the manufacturer is certified from them then it can be ensured for its specification and for its tests. TUV, IEC both give certificinverters and batteries also. Certificates are only accepted where periodic factory inspections are carried out by the certifying body to ensure ongoing compliance with the international standards.

that when the material was procured and comparing it

with the quoted specification on the product.

: Some of the certification standards available for solar PV components

Standards/certifications Certificates/Testing

Performance standards IEC 61215(crystalline)/-IEC 61646(Thin film)

Safety standards IEC 61730-1, 2Performance

IEC 61683 - IEC 62116 - IEC 61727

Safety IEC / EN 62109IEC / EN 62109

Performance and installation

UL 1741 UL-SU 4703 UL-SU 1973,UL 2580


aterial is as per specification and tested

supplier company is certified by international certifications and

There Two international certification are more reliable in solar PV module, which TÜV Rheinland and IECEE (IEC 61715, IEC 61730), other than of these ISO

certification, CE certification, if the manufacturer is certified from them then it can TUV, IEC both give certification for

Certificates are only accepted where periodic factory inspections are carried out by the certifying body to ensure ongoing compliance

procured and comparing it

: Some of the certification standards available for solar PV components

Certificates/Testing

IEC 61215(crystalline)/ IEC 61646(Thin film)

1, 2

IEC / EN 62109-1; IEC / EN 62109-2

SU 1973,UL 2580

Photovoltaic (PV) module factory inspection

During PV module factory inspection

• Existing quality management• Product and manufacturing documen• Workflows • Handling • Manufacturing process controls and in• Receiving, storage and traceability of parts• Packing and shipping of finished goods

Ensure that the manufacturer is doing the following tests

• Insulation test • Measurement of temperature coefficients• Measurement of NOCT • Performance at STC and NOCT• Performance at low irradiance• Outdoor exposure test • Hot-spot endurance test• UV preconditioning

Photovoltaic (PV) module factory inspection -

module factory inspection you should check the following:

Existing quality management Product and manufacturing documentation processes

Manufacturing process controls and in-line metrology Receiving, storage and traceability of parts Packing and shipping of finished goods

manufacturer is doing the following tests:

ment of temperature coefficients

Performance at STC and NOCT Performance at low irradiance

spot endurance test

A general overview of the standard/certificates/codes for PV modules and its

components

Figure 8: Standard/Certificates/Codes for PV modules and its components


: Standard/Certificates/Codes for PV modules and its components


: Standard/Certificates/Codes for PV modules and its components

5. What are the performance guarantee tests after commissioning an


There is no Indian code for the solar PV installation however there are international

codes and standards which needs to be followed to check the installation as a part of

the commissioning process. Installation of DC wiring

62446 which sets out the minimum requirements for PV system documentation,

commissioning tests, and inspection. The standard sets out the information and

documentation that should be provided as a part of final commissioning of the

project. If the PV project installation

ensures that the PV panels and electrical supply connections have been wired up

correctly, the electrical insulation is good, the protective earth connection is as it

should be, and there has been no damage

The testing of the commissioning needs to be done by any third party so that an

independent verification of the system performance can be done.

The testing of a solar plant can be done in a checklist manner to verify and asse

every component of the plant in a broader way, for this plant can be divided in several

parts based on their working characteristics

Plant layout evaluation–

It comprises the whole layout of the plant with the cabling connection. Here

assessment has its base on the some certain points, and result can be shown in

(Yes/No) manner with required comments. The points are

• Assessment of DC cable losses

• Is the wiring network is neat and clean

• Inter row shading observation

• Timing of shadow at the plant due to

• Shading through the boundary

SCADA System Inspection

It comprises of –

• Plant performance

• Weather monitoring make

• Make and parameters measured

5. What are the performance guarantee tests after commissioning an


Indian code for the solar PV installation however there are international


the commissioning process. Installation of DC wiring can be done as per the IEC

s out the minimum requirements for PV system documentation,



project. If the PV project installation follows the specified codes and standards, this



should be, and there has been no damage to cables during installation.


independent verification of the system performance can be done.

The testing of a solar plant can be done in a checklist manner to verify and asse


parts based on their working characteristics –


ts base on the some certain points, and result can be shown in

(Yes/No) manner with required comments. The points are –

Assessment of DC cable losses

Is the wiring network is neat and clean

Inter row shading observation

Timing of shadow at the plant due to different objects

Shading through the boundary

Inspection–

Plant performance

Weather monitoring make

Make and parameters measured


Indian code for the solar PV installation however there are international


can be done as per the IEC

s out the minimum requirements for PV system documentation,



follows the specified codes and standards, this



to cables during installation.


The testing of a solar plant can be done in a checklist manner to verify and assess



ts base on the some certain points, and result can be shown in

• Location of the weather monitoring station

• Integration of weather monitoring station with the

• Is the SCADA system regularly used for MIS plant performance

assessment.

• Are the reports available for the previous SCADA system data review.

• Generation at string level

• Generation at inverter level

• Generation at transformer level

• Generation at site meter level

• Voltage & current at string level and inverter level

• Temperature data recorded by SCADA during the plant operation time

• List of faults recorded by SCADA system during the plant operation

Mounting and Structure Inspection

It comprises –

• Observation of

• Galvanization quality and corrosion.

• Peripheral lighting scheme

• Overall comment on the plant workmanship

• Comments on structure supplier

• Comments on the steel bolts used in the structure

• Comments on welding joints used in the structure

• Comments on structure adequacy to resist the wind load

• Comments on structure alignment.

PV Module and Array Inspection

It comprises –

• Mismatch Table nos.

• Hotspots observed

• Output voltage and current at the string level

• Number of modules in series and parallel in one

• Number of PV modules and model number matches plans and spec

sheets

• Are modules different capacity in a single string

• String fuses or circuit breakers are DC

fuse rating

Location of the weather monitoring station

Integration of weather monitoring station with the SCADA system.

Is the SCADA system regularly used for MIS plant performance

Are the reports available for the previous SCADA system data review.

Generation at string level

Generation at inverter level

Generation at transformer level

at site meter level

Voltage & current at string level and inverter level

Temperature data recorded by SCADA during the plant operation time

List of faults recorded by SCADA system during the plant operation

Mounting and Structure Inspection-

Observation of thermal sagging.

Galvanization quality and corrosion.

Peripheral lighting scheme

Overall comment on the plant workmanship

Comments on structure supplier

Comments on the steel bolts used in the structure

Comments on welding joints used in the structure

ments on structure adequacy to resist the wind load

Comments on structure alignment.

Inspection–

Mismatch Table nos.

Hotspots observed

Output voltage and current at the string level

Number of modules in series and parallel in one string

Number of PV modules and model number matches plans and spec

Are modules different capacity in a single string

String fuses or circuit breakers are DC-rated and no larger than module

SCADA system.

Is the SCADA system regularly used for MIS plant performance

Are the reports available for the previous SCADA system data review.

Temperature data recorded by SCADA during the plant operation time

List of faults recorded by SCADA system during the plant operation

Number of PV modules and model number matches plans and spec

rated and no larger than module

• measurement of shading effect of voltage due to

array

• Check if any Cables are not having enough supports

• Check if the modules are prone to PID

• Comment on Lightning and surge protection scheme

Inverter Commissioning review

It comprises –

• Capacity and make of the inverter• Grounding • Inverter generation• Log Book records• Inverter is installed per the location drawing• Confirm inverter model number matches plans• Ventilation scheme of the inverter room• MPPT condition of the inverters• Over voltage and under voltage protection scheme• Transformer

� It comprises

• Capacity • Transformer Output• Arrangements during oil spillage and storage capacity• Check any oil leakage symptoms at the transformer• Check any loose connection at the cable lugs at transformer

Grid Sub Station (GSS) Inspection

It comprises –

• Capacity • Metering arrangements• Grid tripping details• Check the distance from the plant• check other connected feeders• Check the frequency pattern at the GSS level• Check the monthly reading system• Check a sample joint metering report

measurement of shading effect of voltage due to partial shading on the

Check if any Cables are not having enough supports

Check if the modules are prone to PID

Comment on Lightning and surge protection scheme

Commissioning review –

Capacity and make of the inverter

eration Log Book records Inverter is installed per the location drawing Confirm inverter model number matches plans Ventilation scheme of the inverter room MPPT condition of the inverters Over voltage and under voltage protection scheme Transformer –

mprises –

Transformer Output Arrangements during oil spillage and storage capacity Check any oil leakage symptoms at the transformer Check any loose connection at the cable lugs at transformer

Inspection-

ing arrangements Grid tripping details Check the distance from the plant check other connected feeders Check the frequency pattern at the GSS level Check the monthly reading system Check a sample joint metering report

partial shading on the

Check any loose connection at the cable lugs at transformer

� After assessing the plant at each com

tests will provide us the electricity generation of the plant at different points

like at output of solar PV panels, at combiner box and at inverter output points.

� According to the checklist result evaluate the fau

component, and show them in a generation

manner (Sankey diagram).

� List out the obvious reasons for losses at each component like temperature

degradation effect on the PV modules, temperature effect on i

� Then find the root cause on the basis of checked points of the plant and

obvious reasons for the losses.

After assessing the plant at each component when plant is fully operating, the



According to the checklist result evaluate the fault and losses at every

component, and show them in a generation-loss diagram in percentage (%)

manner (Sankey diagram).

List out the obvious reasons for losses at each component like temperature

degradation effect on the PV modules, temperature effect on inverter etc.

Then find the root cause on the basis of checked points of the plant and

obvious reasons for the losses.

ponent when plant is fully operating, the



lt and losses at every

loss diagram in percentage (%)

List out the obvious reasons for losses at each component like temperature

nverter etc.

Then find the root cause on the basis of checked points of the plant and

6. What are the performance bank guarantees taken from the suppliers

many years-

The EPC contractor is responsible for detailed engineering and design, procurement, and installation and commissioning activities. There is always a fixed timeframe specified for completing the each activity and the EPC contract should also specify the project completion date. In case of delays there should be a clear provision for the liquidated damages (LDs). EPC contracts containsof calculation of PR should be part of the EPC contract and a sample calculationthe monitoring plan should be attached in the EPC contract.

EPC contractor provides performance security to protectbank guarantee (5-10% of thethe desired power output as per the contract obligat

Defects liability guarantee from the Suppliers

The defect liability guarantee is generally for commissioning of the project. Defect guarantees are also separately specified for some of the critical components sucby the original equipment suppliers.

In the most cases, the Operation & Maintenance Agreement is signed with the same EPC Contractor, at least for 5 years and in some cases till the tenor of the loan. Durthis period the EPC Contractor guarantees generation. The amount and mechanism of guaranteeing generation is of immense importance to the Project Developer and the Lending Institution.

Warrantees from the PV Module Manufacturers are for 25 years

Manufacturer warrants for every PV

performance warranty:

• For 5 years as of the production date a performance of a PV

least 95 % of the nominal power indicated on the nameplate.

• For 12 years as of the production d

least 90 % of the nominal power indicated on the nameplate



• For 25 years as of the pr


6. What are the performance bank guarantees taken from the suppliers

tor is responsible for detailed engineering and design, procurement, and installation and commissioning activities. There is always a fixed timeframe specified for completing the each activity and the EPC contract should also specify the

date. In case of delays there should be a clear provision for the liquidated damages (LDs). EPC contracts contains PR guarantees clause, of calculation of PR should be part of the EPC contract and a sample calculation

ould be attached in the EPC contract.

EPC contractor provides performance security to protect developer in the form of a 10% of the EPC contract) if the plant performance does not meet

the desired power output as per the contract obligations, it can be liquidated.

guarantee from the Suppliers:

guarantee is generally for a period of 12 months post commissioning of the project. Defect guarantees are also separately specified for some of the critical components such as PV modules and inverters, for a longer period by the original equipment suppliers.

In the most cases, the Operation & Maintenance Agreement is signed with the same EPC Contractor, at least for 5 years and in some cases till the tenor of the loan. Durthis period the EPC Contractor guarantees generation. The amount and mechanism of guaranteeing generation is of immense importance to the Project Developer and the

antees from the PV Module Manufacturers are for 25 years

facturer warrants for every PV-module as a voluntary, independent

For 5 years as of the production date a performance of a PV

least 95 % of the nominal power indicated on the nameplate.








tor is responsible for detailed engineering and design, procurement, and installation and commissioning activities. There is always a fixed timeframe specified for completing the each activity and the EPC contract should also specify the

date. In case of delays there should be a clear provision for the PR guarantees clause, the method

of calculation of PR should be part of the EPC contract and a sample calculation and

developer in the form of a the plant performance does not meet

ions, it can be liquidated.

a period of 12 months post commissioning of the project. Defect guarantees are also separately specified for

h as PV modules and inverters, for a longer period

In the most cases, the Operation & Maintenance Agreement is signed with the same EPC Contractor, at least for 5 years and in some cases till the tenor of the loan. During this period the EPC Contractor guarantees generation. The amount and mechanism of guaranteeing generation is of immense importance to the Project Developer and the

-module as a voluntary, independent

For 5 years as of the production date a performance of a PV-module of at

ate a performance of a PV-module of at


oduction date a performance of a PV-module of at

c) Linear performance guarant

market come with a 25

guarantee). In most cases this means a guaranteed electrical production for 10

years at 90% of rated power output and 25 years at 80%.

JA Solar, First Solar, Canadian Solar, Sanyo, Sharp and most other solar panel manufacturers uses this standard model of degradation in their warranties. However, some manufacturers set themselves apart from the competition by offering better performance guarante

SunPower has recently updated their warranty (April 1st, 2013) and guarantees 95%

of rated power for the first 5 years, declining by no more than 0.4% per year the

following 20 years. This means SunPower guarantees 87% of rated power output at

25 years – by far the best warranty on the market.

Yingli Solar`s Panda solar panels guarantees 82% of rated power output at 25 years.

SolarWorld and Trina use linear performance guarantees (see graph below)

Graph

Linear performance guarantee: The majority of solar panels on today`s

market come with a 25-year long warranty (also known as a performance


years at 90% of rated power output and 25 years at 80%.

r, First Solar, Canadian Solar, Sanyo, Sharp and most other solar panel manufacturers uses this standard model of degradation in their warranties. However, some manufacturers set themselves apart from the competition by offering better performance guarantees:



This means SunPower guarantees 87% of rated power output at

by far the best warranty on the market.



Graph 1: Solar Panel Warranty Comparison

The majority of solar panels on today`s

year long warranty (also known as a performance


r, First Solar, Canadian Solar, Sanyo, Sharp and most other solar panel manufacturers uses this standard model of degradation in their warranties. However, some manufacturers set themselves apart from the competition by



This means SunPower guarantees 87% of rated power output at



• For achieving better performance during the operation period solar module

should be sorted based on different

provide power

impact that module mismatc

selecting a module.

preferable to one with 0% to 5%.

7. How to ensure that the module is in line with SECI standards

61215, IEC 61730 and IEC 61701

To ensure that the module is in l

have following procedure.

a) Ask the potential company to provide written proof that their module conform

to IEC 61215, IEC 61730

b) Diagnostic: Visual insp

ensuring that module is in line with SECI standards.

c) Apart from certification module performance can be ensured by

how many On-grid system they have installed and can talk to the project

owners about the performance of the solar module.

d) We can also know about the module performance by

many year the company is in the PV

A module design shall be judged to have passed the qualification test,and therefore to

be IEC type approved if each sample meet the following criteria:

a) The degradation of the maximum power output at standard conditions (STC)

does not exceed 5% after each test nor 8% after each test sequence;

b) The requirement of insulation and wet leakage test are met;

c) No major visible damage (breakage or cracks in cells or glass, detachment of

the embedding mass, etc.)

d) No sample has exhibited any open circuit or ground fault during the tests.

e) For IEC 61646 only (Thin film) : the measured maximum output power after

final light-soaking shall not be less than 90% of the minimum value specified

by the manufacturer.

For achieving better performance during the operation period solar module

should be sorted based on different tolerances. Major module manufacturer

provide power tolerance for their modules. Understanding the minimal

impact that module mismatch has on energy losses is also

selecting a module. For example a module with a 0% to 1% power

preferable to one with 0% to 5%.

to ensure that the module is in line with SECI standards requirement (IEC

61730 and IEC 61701)-

To ensure that the module is in line with SECI standards requirement at

have following procedure.

Ask the potential company to provide written proof that their module conform

61730 i.e. product should be registered and IEC certified.

Visual inspection can be done for damage and hotspots for

ensuring that module is in line with SECI standards.

Apart from certification module performance can be ensured by

grid system they have installed and can talk to the project

out the performance of the solar module.

We can also know about the module performance by knowing

many year the company is in the PV industry.


approved if each sample meet the following criteria:

The degradation of the maximum power output at standard conditions (STC)


The requirement of insulation and wet leakage test are met;

o major visible damage (breakage or cracks in cells or glass, detachment of

the embedding mass, etc.)

No sample has exhibited any open circuit or ground fault during the tests.

For IEC 61646 only (Thin film) : the measured maximum output power after

soaking shall not be less than 90% of the minimum value specified

by the manufacturer.

For achieving better performance during the operation period solar module

Major module manufacturer

for their modules. Understanding the minimal

also valuable when

a module with a 0% to 1% power tolerance

requirement (IEC

ine with SECI standards requirement at client end we

Ask the potential company to provide written proof that their module conform

product should be registered and IEC certified.

and hotspots for

Apart from certification module performance can be ensured by knowing that

grid system they have installed and can talk to the project

knowing that for how


The degradation of the maximum power output at standard conditions (STC)


o major visible damage (breakage or cracks in cells or glass, detachment of

No sample has exhibited any open circuit or ground fault during the tests.

For IEC 61646 only (Thin film) : the measured maximum output power after

soaking shall not be less than 90% of the minimum value specified

Code Qualification test Test description /Pass criteria

10.1 Visual Inspection according defined inspect10.2 Performance at

STC cell irradiance distribution according to IEC 60904

10.3 Insulation Test 1000 VDC + twice the open circuit voltage of the system at STC for1 min, le

10.4 Measurement of Temperature coefficients

Determination of the temperature coefficients of short circuit current Coefficients and open circuit voltage in a 40°C interval

10.5 Measurement of NOCT

Total solar iraccording to IEC 60904

10.6 Performance at NOCT

Cell temperature = NOCTirradiance distribution according to IEC 60904

10.7 Performance at low Irradiance

Cell temperature = 25°C,Spectral irradiance distribution according to IEC 60904

10.8 Outdoor Exposure Test

60 kWh/m² solar irradiation

10.9 Hot-Spot Endurance Test

5 one hour exposures to 1000 W/m² irradiance in worstspot condition

10.10 UV-Exposure according IEC UV-61345

7,5 kWh/m² UVradiation (280

10.11 Thermal Cycling 50 and 200 cycles

10.12 Humidity Freeze Test

10 cycles

10.13 Damp Heat 1000 h at +85°C, 85% RH

10.14 Robustness of Terminations

As in IEC 60068

10.15 Twist Test Deformation angle

10.16 Mechanical Load Test

Two cycles of 2400 Pa uniform load, applied for 1 h to front and back surfaces in turn

10.17 Hail Test 25 mm diameter ice ball at 23 m/s, directed at 11 impact locations

10.18* Light soaking Light exposure of 800 W/mwithin 2 %

10.19* Annealing Heat soak at 85 °C until Pmax is stable within 2 %

10.20* Wet leakage current test

Water spray of terminals and edge immersion with 500 V d.c. appli

* Tests only relevant for IEC 61646 qualification

Table 2: Overview of IEC tests

Test description /Pass criteria

according defined inspection list cell temperature = 25 °C, irradiance = 1000 W/m²,irradiance distribution according to IEC 60904-3 1000 VDC + twice the open circuit voltage of the system at STC for1 min, leakage current < 50 µA, isolation resistance >50 M at 500 VDC


Total solar irradiance = 800 W/m² , Spectral irradiance distribuaccording to IEC 60904-3, Wind speed = 1 m/s Cell temperature = NOCT, Irradiance = 800 W/m²,Spectral irradiance distribution according to IEC 60904-3 Cell temperature = 25°C,Irradiance = 200 W/m², Spectral irradiance distribution according to IEC 6090460 kWh/m² solar irradiation

5 one hour exposures to 1000 W/m² irradiance in worstspot condition

7,5 kWh/m² UV-radiation (280 - 320 nm and ≥15 kWh/mradiation (280 - 400 nm) at 60°C module temperature

50 and 200 cycles -40°C to +85°C

10 cycles -40°C to +85°C, 85% RH

1000 h at +85°C, 85% RH

As in IEC 60068-2-21

Deformation angle 1.2° over the module diagonal

Two cycles of 2400 Pa uniform load, applied for 1 h to front and back surfaces in turn 25 mm diameter ice ball at 23 m/s, directed at 11 impact locations

Light exposure of 800 W/m2 to 1000 W/m2, until Pmax is stable within 2 %

Heat soak at 85 °C until Pmax is stable within 2 %

Water spray of terminals and edge immersion with 500 V d.c. applied to determine leakage current

* Tests only relevant for IEC 61646 qualification

, spectral

1000 VDC + twice the open circuit voltage of the system at STC for1 akage current < 50 µA, isolation resistance >50 M at 500 VDC


Spectral irradiance distribution Spectral

Spectral irradiance distribution according to IEC 60904-3

5 one hour exposures to 1000 W/m² irradiance in worst-case hot-

≥15 kWh/m² 400 nm) at 60°C module temperature

Two cycles of 2400 Pa uniform load, applied for 1 h to front and

25 mm diameter ice ball at 23 m/s, directed at 11 impact locations

to 1000 W/m2, until Pmax is stable

Water spray of terminals and edge immersion with 500 V d.c.

8. How to ensure peak output wattage is more than 90 % in first ten years and more


To ensure that peak output wattage is more than

than 80% at the end of 25

a) Service certificate:

the PV Module will amount to at least 97% of effective output durin

year after purchase of the product and as of the second year after purchase of

the product, the effective output will decline annually by no more than 0.7%

for a period of 24 years, so that by the end of the 25th year after purchase an

actual output of at least 80.2% of effective output will be achieved. Now days

modules with linear performance guarantee are also available.

b) Degradation factor/

check for the degradation factor which is generally

c) Power Tolerance:

that the module should produce at least 171 W (200 W × 0.95 power tolerance

× 0.9) under STC for the first 10 years. For the next 10 years, the module

should produce at least 152 W (100 W × 0.95 power tolerance × 0.8).

Construction and Maintenance Practices

module life:

The guaranteed power output from a solar

adopting good construction and

a) Cleaning the solar modules at schedule on monthly,

in improved efficiency and hence the performance.

b) Hot spot prevention: To prevent the cells from hot spots bypass d

all standard modules nowadays.

diodes is functioning, the diode function should be checked on each new module

before it is shipped from the factory.

spots or low shunt resistances;

c) Preventing open circuits

even five) tabbing ribbons each soldered at multiple locations or

electrically bonded to the cell over a large area. This provi

protection against open circuiting.



To ensure that peak output wattage is more than 90% in first ten years and more

than 80% at the end of 25th year the clients has to ask/look for the following :

Service certificate: Now days companies guarantees that the actual output of

will amount to at least 97% of effective output durin




utput of at least 80.2% of effective output will be achieved. Now days

modules with linear performance guarantee are also available.

Degradation factor/rate: To ensure the above performance limits always

check for the degradation factor which is generally ranges as 0.25%

Tolerance: A 200 W module with a power tolerance of +/



ce at least 152 W (100 W × 0.95 power tolerance × 0.8).

Construction and Maintenance Practices can also help in maintaining the longer

power output from a solar PV module can also

ng good construction and maintenance practices as follows.

the solar modules at schedule on monthly, quarterly or annual basis help

in improved efficiency and hence the performance.

To prevent the cells from hot spots bypass diodes are used in

all standard modules nowadays. To ensure that this safety feature of the bypass


before it is shipped from the factory. Proper screening to remove cells with ho

spots or low shunt resistances;

circuits: cells should be tabbed with multiple (two, three, four, or

even five) tabbing ribbons each soldered at multiple locations or

bonded to the cell over a large area. This provides redundancy and

protection against open circuiting.


90% in first ten years and more

year the clients has to ask/look for the following :

Now days companies guarantees that the actual output of

will amount to at least 97% of effective output during the first




utput of at least 80.2% of effective output will be achieved. Now days

To ensure the above performance limits always

ranges as 0.25%-0.7%.

A 200 W module with a power tolerance of +/-5% means



ce at least 152 W (100 W × 0.95 power tolerance × 0.8).

can also help in maintaining the longer

also be ensured by

or annual basis help

iodes are used in

To ensure that this safety feature of the bypass


Proper screening to remove cells with hot

cells should be tabbed with multiple (two, three, four, or

even five) tabbing ribbons each soldered at multiple locations or otherwise

des redundancy and

d) Preventing ground faults from

follow specific design rules that forbid the attachment of conductive mounting

hardware directly onto polymeric back

components of the electric circuit. Module framing should be mounted outside of the

active area, meeting the creep

voltage.

e) Replacing the broken glass

conditions such as poor packaging during transportation, during installation or by

hail and stone throwing.

Preventing ground faults from occurring: Module mounting systems should


hardware directly onto polymeric back-sheets behind solar cells and/or other


active area, meeting the creep age and clearance distances for the rated system

Replacing the broken glass: In most cases glass breaks are caused by

such as poor packaging during transportation, during installation or by

hail and stone throwing. Modules with broken glass should always be replaced.

Module mounting systems should


d solar cells and/or other


age and clearance distances for the rated system

are caused by external

such as poor packaging during transportation, during installation or by

Modules with broken glass should always be replaced.

Some Typical PV modules Field Failures

The commercial success of PV is based on lo

deployed PV modules. Today most PV modules are warranted for 25

maximum allowable degradation rate of 0.8%/year.

These modules are typically qualified/certified to:

• IEC 61215 for Crystalline Silicon Modul

• IEC 61646 for Thin Film Modules

• IEC 62108 for CPV Modules

These qualification tests do an excellent job

process flaws that could lead to premature field failures.

that have been observed f

• Broken cells

• Broken interconnects

• Corrosion of cells, metals and connectors

• Delamination/loss of adhesion between layers

• Loss of elastomeric properties of encapsulant or back

• Encapsulant discoloratio

• Solder bond failures

• Broken glass

• Glass corrosion

• Hot Spots

• Ground faults due to breakdown of insulation package

• Junction box and module connection failures

• Structural failures

• Bypass Diode failures

• Open circuiting leading to arcing

• Potential Induced De

PV modules Field Failures

The commercial success of PV is based on long term reliability and safety of the

deployed PV modules. Today most PV modules are warranted for 25

maximum allowable degradation rate of 0.8%/year.

These modules are typically qualified/certified to:

IEC 61215 for Crystalline Silicon Modules

IEC 61646 for Thin Film Modules

IEC 62108 for CPV Modules

These qualification tests do an excellent job of identifying design, materials and

process flaws that could lead to premature field failures. The various field failures

that have been observed for different types of PV modules are listed below.

Broken interconnects

Corrosion of cells, metals and connectors

Delamination/loss of adhesion between layers

Loss of elastomeric properties of encapsulant or back-sheet

Encapsulant discoloration

Solder bond failures

Ground faults due to breakdown of insulation package

Junction box and module connection failures

Structural failures

Bypass Diode failures

Open circuiting leading to arcing

Potential Induced Degradation

ng term reliability and safety of the

deployed PV modules. Today most PV modules are warranted for 25 years with a

design, materials and

The various field failures

or different types of PV modules are listed below.

Examples of Field Failures

(a)Broken interconnects

(c)Delamination Figure

Examples of Field Failures

(a)Broken interconnects (b)Broken cells

(c)Delamination (d)Hot Spots

Figure 9: Common PV Module Failure & Damages

Additional Field Failures for Thin Films

(a) Electrochemical corrosion

(c) Encapsulant Discoloration

Figure

Additional Field Failures for Thin Films

(a) Electrochemical corrosion (b) Broken glass corrosion

(c) Encapsulant Discoloration (d) Structural Failures

Figure 10: Some Additional PV Module Failure

(d) Structural Failures

9. What should be the liquidated damages for non performance of the module?

A solar manufacturer also provides

products in long term and short term basis. Gener

term warranties for their products. Some of the warranties provided by PV

manufacturer are:

a) Product warranty

A manufacturer warrants

respective PRODUCTION DATE to the END

PV-module is free of material defects.

In a warranty case manufacturer will either repair the defected PV

charge or replace the same by a functional PV

charge. In case that the respective PV

the company at the time of the warranty case, company retains the right to supply

a functionally identical PV

type. The remaining period of the original warranty period applies to newly

supplied PV-modules.

b) Performance warranty

PV manufacturers warrants for every PV


• For 5 years as of the production date

95 % of the nominal power indicated on the nameplate.



• For 18 years as of the





charge or replace the same by a functional PV

charge. In case that the respective PV

the company at the time of the

a functionally identical PV

should be the liquidated damages for non performance of the module?

A solar manufacturer also provides Warranty and Performance Guarantee for their

products in long term and short term basis. Generally PV manufacturers provide long


Product warranty-Ten Years Repair, Replacement or Refund

A manufacturer warrants for each PV-module for a period of 10 years as o

respective PRODUCTION DATE to the END-CUSTOMER that the respective

-module is free of material defects.


charge or replace the same by a functional PV-module of the same type, free of

charge. In case that the respective PV-module type is no longer manufactured by


a functionally identical PV-module of the same or higher capacity of a diffe


Performance warranty

warrants for every PV-module as a voluntary,


For 5 years as of the production date a performance of a PV-module of at least

95 % of the nominal power indicated on the nameplate.







e manufacturer will either repair the defected PV

charge or replace the same by a functional PV-module of the same type, free of

charge. In case that the respective PV-module type is no longer manufactured by


a functionally identical PV-module of the same or higher capacity of a different

should be the liquidated damages for non performance of the module?

Warranty and Performance Guarantee for their

ally PV manufacturers provide long


Ten Years Repair, Replacement or Refund

-module for a period of 10 years as of the

-CUSTOMER that the respective

In a warranty case manufacturer will either repair the defected PV-module free of

me type, free of

-module type is no longer manufactured by


-module of the same or higher capacity of a different


-module as a voluntary, independent

-module of at least


date a performance of a PV-module of at


e manufacturer will either repair the defected PV-module free of

-module of the same type, free of

-module type is no longer manufactured by

warranty case, company retains the right to supply

-module of the same or higher capacity of a different


supplied PV-modules.

Generally there are no LD clauses applicable on the module manufacturer. They

replace the PV modules in case the module

The PV module manufacturers do not offer the

the replacement period.

10. What should be insurance requirement to cover loss of

During the operation period the following insurances are taken by the [roject developer:

a) Theft and damage of equipment/projectb) Machinery Breakdownc) Force Majeure d) Risk

There are several insurance

due to non generation of the plant


This policy cover again

guarantee 90% of the performance of the PV plant.

insurer will compensate for the reduced yields, if the prognosticated energy

returns p.a. accordant with profit survey

about more than 10 %.

The insurer provides a 1 year cover for single installations and a 1 or 5 years

cover for installations covered by a policy.

A 5 year covers for single PV

acceptance by the insurer.



replace the PV modules in case the module defects are observed post installations.

The PV module manufacturers do not offer the LD for the loss of generation during

d.

should be insurance requirement to cover loss of profit?

During the operation period the following insurances are taken by the [roject

Theft and damage of equipment/project Machinery Breakdown

There are several insurance products which helps to recover the loss due to profit

due to non generation of the plant:


his policy cover against reduced yields including Lack of Sun Cover , insure and

guarantee 90% of the performance of the PV plant. According to this policy the


p.a. accordant with profit survey or profit expertise has fallen short

about more than 10 %.


cover for installations covered by a policy.

for single PV-installation only on request and after u

acceptance by the insurer.



are observed post installations.

LD for the loss of generation during

During the operation period the following insurances are taken by the [roject

helps to recover the loss due to profit

All risk policy, including Loss of Income and Reduced yield cover –

st reduced yields including Lack of Sun Cover , insure and

According to this policy the


or profit expertise has fallen short


installation only on request and after upfront

Insured and non-insured reduced yield

a) Insured reduced yield Insurer will compensate reduced yield by:

• a reduced global ultraviolet radiation in comparison with profit

survey,

• shortcomings of components,

• inner operation

components.

• above-average or excessive wear and tear and

contamination/pollution of components

b) Non-Insured reduced yields Insurer does not compensate reduced yield

without concern to operating causes by:

• Incorrect handling by the carrier of the plant;

• Arbitrary changes at the insured object by the carrier of the plant;

• Failure of the injection counter;

• Power supply interruption;

• Checks and maintenance works;

• Permanent shadow, disregarded in the profit

(a) External disasters, Production Loss, Insurance backed warranty for solar

panels- 20 years and inverters 7.5 years.

• Insured is the photovoltaic plant described in the insurance contract and all

parts which belong to the PV plant, in particular also

• Fences, cabling

• Devices which are for the purpose of infeed such as transformers, network

infeed stations and underground cables

• Foundations, load-

• Operational buildings and containers on the plant

• Transmission equipment for monitori

Third Party Liability insurance

Liability insurance purchased by an investor from an insurer for protection against the claims of another third party.Third Party Liability covering loss of human life, engineers and workmen and also covering the risks of damage to the thirdparty/material/equipment/properties

insured reduced yield

Insured reduced yield Insurer will compensate reduced yield by:

a reduced global ultraviolet radiation in comparison with profit

survey,

shortcomings of components,

inner operation damages of photovoltaic modules and electronic

components.

average or excessive wear and tear and

contamination/pollution of components

Insured reduced yields Insurer does not compensate reduced yield

without concern to operating causes by:

correct handling by the carrier of the plant;

Arbitrary changes at the insured object by the carrier of the plant;

Failure of the injection counter;

Power supply interruption;

Checks and maintenance works;

Permanent shadow, disregarded in the profit survey.

External disasters, Production Loss, Insurance backed warranty for solar

20 years and inverters 7.5 years.

Insured is the photovoltaic plant described in the insurance contract and all

parts which belong to the PV plant, in particular also:

Devices which are for the purpose of infeed such as transformers, network

infeed stations and underground cables

-bearing constructions

Operational buildings and containers on the plant

Transmission equipment for monitoring.

Third Party Liability insurance-

Liability insurance purchased by an investor from an insurer for protection against the claims of another third party. The Bidder shall also take insurance for Third Party Liability covering loss of human life, engineers and workmen and also covering the risks of damage to the thirdparty/material/equipment/properties

Insured reduced yield Insurer will compensate reduced yield by:

a reduced global ultraviolet radiation in comparison with profit

damages of photovoltaic modules and electronic

average or excessive wear and tear and

Insured reduced yields Insurer does not compensate reduced yield

Arbitrary changes at the insured object by the carrier of the plant;

survey.

External disasters, Production Loss, Insurance backed warranty for solar

Insured is the photovoltaic plant described in the insurance contract and all

Devices which are for the purpose of infeed such as transformers, network

Liability insurance purchased by an investor from an insurer for protection The Bidder shall also take insurance for

Third Party Liability covering loss of human life, engineers and workmen and also covering the risks of damage to the thirdparty/material/equipment/properties

during execution of the contract. Example of claim caseplant blows away and hits a third party property or a person.

during execution of the contract. Example of claim case: If a module from your PV plant blows away and hits a third party property or a person.

: If a module from your PV

Appendix

Below are the some of the companies along with the certified tests which are done in that

company.


1. Insulation test 2. Performance at STC and NOCT3. Performance at low irradiance4. Outdoor exposure test 5. Hot-spot endurance test6. UV preconditioning 7. Thermal cycling test 8. Humidity freeze test 9. Damp heat test 10. Robustness of termination test11. Wet leakage current test12. Mechanical load test 13. Hail test 14. Bypass diode thermal test15. Bonding Path Resistance Test16. Wet Insulation-Resistance Test17. Terminal Torque Test 18. Impact Test 19. Water Spray Test 20. Accelerated Aging Test 21. Humidity Test 22. Corrosive Atmosphere Test23. Partial discharge-test MST 15lic Coatin24. PID Test 25. FTIR spectrometer 26. UV/Visible spectrometer27. Spectral Ellipsometry 28. LID test.

Appendix


conducted by Jinco Solar in their production process


spot endurance test

Robustness of termination test Wet leakage current test

Bypass diode thermal test Bonding Path Resistance Test

Resistance Test

Corrosive Atmosphere Test test MST 15lic Coating Thickness Test

UV/Visible spectrometer


in their production process


1. Insulation test 2. Measurement of temperature coefficients3. Measurement of NOCT 4. Performance at STC and NOCT5. Performance at low irradiance6. Outdoor exposure test 7. Hot-spot endurance test8. UV preconditioning 9. Thermal cycling test 10. Humidity freeze test 11. Damp heat test 12. Robustness of termination test13. Wet leakage current test14. Mechanical load test 15. Hail test 16. Bypass diode thermal test17. Bonding Path Resistance Test18. Wet Insulation-Resistance Test19. Terminal Torque Test 20. Impact Test 21. Water Spray Test 22. Accelerated Aging Test 23. Humidity Test 24. Corrosive Atmosphere Test25. Partial discharge-test MST 15lic Coating Thickness Test26. PID Test 27. FTIR spectrometer 28. UV/Visible spectrometer29. Spectral Ellipsometry 30. LID test.

conducted by JA Solar in their production process

Measurement of temperature coefficients


spot endurance test


rmal test Bonding Path Resistance Test

Resistance Test

Corrosive Atmosphere Test test MST 15lic Coating Thickness Test

UV/Visible spectrometer



1. Insulation test 2. Measurement of temperature coefficients3. Measurement of NOCT 4. Performance at STC and NOCT5. Performance at low irradiance6. Outdoor exposure test 7. Hot-spot endurance test8. UV preconditioning 9. Thermal cycling test 10. Humidity freeze test 11. Damp heat test 12. Robustness of termination test13. Wet leakage current test14. Mechanical load test 15. Hail test 16. Bypass diode thermal test17. Bonding Path Resistance Test18. Wet Insulation-Resistance Test19. Terminal Torque Test 20. Impact Test 21. Water Spray Test 22. Accelerated Aging Test 23. Humidity Test 24. Corrosive Atmosphere Test25. PID Test 26. FTIR spectrometer 27. Spectral Ellipsometry 28. LID test.

conducted by C Sun in their production process



spot endurance test



Resistance Test

Corrosive Atmosphere Test



1. Insulation test 2. Measurement of temperature coefficients3. Measurement of NOCT 4. Performance at STC and NOCT5. Performance at low irradiance6. UV preconditioning 7. Thermal cycling test 8. Humidity freeze test 9. Damp heat test 10. Wet leakage current test11. Mechanical load test 12. Bypass diode thermal test13. Bonding Path Resistance Test14. Wet Insulation-Resistance Test15. Terminal Torque Test 16. Impact Test 17. Water Spray Test 18. Accelerated Aging Test 19. Humidity Test 20. FTIR spectrometer 21. UV/Visible spectrometer22. Photoluminescence spectrometer23. Spectral Ellipsometry 24. LID test.

conducted by Renesola in their production process



Wet leakage current test


Resistance Test

UV/Visible spectrometer Photoluminescence spectrometer


solar pv plant quality assurance checkpoints v2

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