A report by FIrstgreen Consulting Pvt Ltd

1. A report by Firstgreen Consulting Pvt Ltd
Solar PV Module Quality
Assessment

2. 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:................................
4. How to ensure that the Supplier is supplying the material which was tested and is
...........................................................................................................................
...........................................5
............................................5
...........................................5
Check points and parameter on input side that is raw material with quality
.........................................6
It is import that the PV module is made of glass with anti reflective (ARC) coating (ARC): 6
................................................... 6
.......................... 7
.................................. 7
Ensure that the Back sheet should have the UV protection and moisture protection
...................................... 8
.................................................. 8
.................................................. 9
........................................... 9
...........................10
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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
4. How to ensure that the Supplier is supplying the material which was tested and is
...........................14

3. 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
5. What are the performance guarantee tests after commissioning and methods to
ensure that vendor will ensure compliance................................................................
................................................................................................
................................................................................................
Mounting and Structure Inspection-.........................................................................................
PV Module and Array Inspection– ............................................................................................
Inverter Commissioning review –..............................................................................................
) Inspection- ............................................................................................
6. What are the performance bank guarantees taken from the suppliers and for how
................................................................................................................................
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
5. What are the performance guarantee tests after commissioning and methods to
..............................................17
........................................... 17
........................................ 17
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............................ 18
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6. What are the performance bank guarantees taken from the suppliers and for how
...........................................21
........................................ 21
.......................................... 21
......................... 22
at the module is in line with SECI standards requirement (IEC
...............................23
to ensure peak output wattage is more than 90 % in first ten years and more
.................................25
.............................................. 25
................................... 25
............................................... 25
can also help in maintaining the longer module life:
................................................... 25
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4. 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
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................................................................
Table 1: Some of the certification standards available for solar PV components
................................................................................................
Graph 1: Solar Panel Warranty Comparison................................................................................................................................
at should be the liquidated damages for non performance of the module?.......30
........................................... 30
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................................... 35
....................................... 36
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....................................................... 6
.................................................... 7
................................ 8
............................................... 9
......................... 12
........................................ 12
Figure 7: Solar PV Module under PID Test (a) Normal PV Panel (b) Degraded PV Panel........ 13
............................ 16
..................................... 28
.......................................... 29
Table 1: Some of the certification standards available for solar PV components..................... 14
...................................... 24
.....................................22

5. 1. Check points and parameter on input side that is raw material with quality
checks and testing procedures:
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.
Check points and parameter on input side that is raw material with quality
checks and testing procedures:
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
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
: 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
Check points and parameter on input side that is raw material with quality
and technology parameters which
reflective (ARC)
Use of ARC coating on the PV module glass reduces light
the solar cells. Typically
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
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

6. 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
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
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
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
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

7. 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
moisture protection, electrical insulation, and some degree of durability.
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
~300 um. Today, it is common for manufacturers to test beyond the 1000
hour damp heat requirement, thereby placing greater importance on the
nating adhesives. As the current demand for back
increased, the need for lower cost / higher durability options has intensified.
should have a very high transmitivity feature:
PV modules as a layer of protection against the elements. In Thin film
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
should have the UV protection and moisture
o provide UV and
moisture protection, electrical insulation, and some degree of durability.
Technology advances, coupled with changes in IEC standards, increased back-
nce was mandated to pass
sheet thickness of
~300 um. Today, it is common for manufacturers to test beyond the 1000
hour damp heat requirement, thereby placing greater importance on the
nating adhesives. As the current demand for back-sheets has
increased, the need for lower cost / higher durability options has intensified.
: Glass is used in
gainst the elements. In Thin film
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% of

8. 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
solar cells is taken by the busbar made of silver foil. A busbar on the module
surface area reduces its exposed area to the light, hence some of the PV
le 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 suppliers use the three busbar design
which increases the conductive area and increases the cell resistive power
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
solar cells is taken by the busbar made of silver foil. A busbar on the module
area to the light, hence some of the PV
le 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
ppliers use the three busbar design
which increases the conductive area and increases the cell resistive power
chances of generated current

9. 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-
Following are the check points for the manufacturing process and customer hold
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. Wire-saw wafer slicing is one
of the key production technologies for industrial crystalline silicon PV cells,
d improvements in wafer slicing technology have resulted in a reduction in
raw wafer thickness from 370 μm to 180 μm for Sharp industrial
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
surface as usual but produces a texture where the etch rate does not depend
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
roughness and topography produced by dry texturing can be controlled by the
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
by submersing the appliance into water with one lead attached to the electrical
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
photovoltaic module. In particular, photoluminescence spectroscopy may be
used to characterize band gap, defect densities, and recombination
Following are the check points for the manufacturing process and customer hold
Wafer processing technology affect the PV module quality: The raw, high-
purity polysilicon material used for the fabrication of crystalline silicon solar
saw wafer slicing is one
of the key production technologies for industrial crystalline silicon PV cells,
d improvements in wafer slicing technology have resulted in a reduction in
raw wafer thickness from 370 μm to 180 μm for Sharp industrial
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
surface as usual but produces a texture where the etch rate does not depend
texturing on one side only,
textured wafers is
textured wafers. Moreover, the surface
roughness and topography produced by dry texturing can be controlled by the
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
by submersing the appliance into water with one lead attached to the electrical
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
photovoltaic module. In particular, photoluminescence spectroscopy may be
used to characterize band gap, defect densities, and recombination

10. 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
mechanisms in the semiconductor. Unfortunately, existing photoluminescence
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
mechanisms in the semiconductor. Unfortunately, existing photoluminescence
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.

11. 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
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
ctive 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.
: Solar Modules under Electro Luminescence test
Module Tolerance should be minimum: It is advisable to select the PV
modules with a positive tolerance. Many PV module suppliers provides
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
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
ctive modules or underperforming modules and park them separately
in a different lot. EL testing is performed just before the packing of the PV
It is advisable to select the PV
modules with a positive tolerance. Many PV module suppliers provides
of the range of -5%+5%
ge) tolerance which is difficult to

12. 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.
It is advised to select a PID free module which has been tested for the PID test
a temperature of 85 degrees Celsius, 85% relative humidity
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
(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.
It is advised to select a PID free module which has been tested for the PID test
85 degrees Celsius, 85% relative humidity, 1000V
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
(a) Normal PV Panel (b) Degraded PV Panel

13. 4. How to ensure that the Supplier is supplying the material which was
as per specification-
To ensure that the Supplier is supplying the m
perfectly, 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 m
are 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.
Table 1: Some of the certification standards available for solar PV components
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 m
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. TUV, IEC both give certific
inverters 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, 2
Performance IEC 61683
- IEC 62116
- IEC 61727
Safety IEC / EN 62109
IEC / EN 62109
Performance and installation UL 1741
UL-SU 4703
UL-SU 1973,UL 2580
4. How to ensure that the Supplier is supplying the material which was tested and is
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

14. 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

15. 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
A general overview of the standard/certificates/codes for PV modules and its
: Standard/Certificates/Codes for PV modules and its components
A general overview of the standard/certificates/codes for PV modules and its
: Standard/Certificates/Codes for PV modules and its components

16. 5. What are the performance guarantee tests after commissioning an
ensure that vendor will ensure compliance
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
ensure that vendor will ensure compliance
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 can be done as per the IEC
s 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 follows the specified codes and standards, this
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 to cables during installation.
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 –
It comprises the whole layout of the plant with the cabling connection. Here
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
5. What are the performance guarantee tests after commissioning and methods to
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
can be done as per the IEC
s 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
follows the specified codes and standards, this
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
to cables during installation.
The testing of the commissioning needs to be done by any third party so that an
The testing of a solar plant can be done in a checklist manner to verify and assess
every component of the plant in a broader way, for this plant can be divided in several
It comprises the whole layout of the plant with the cabling connection. Here
ts base on the some certain points, and result can be shown in

17. • 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

18. • 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

19. 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
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 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
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.
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

20. 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 contains
of calculation of PR should be part of the EPC contract and a sample calculation
the monitoring plan should be attached in the EPC contract.
EPC contractor provides performance security to protect
bank guarantee (5-10% of the
the 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 suc
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. Dur
this 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 18 years as of the production date a performance of a PV
least 85 % of the nominal power indicated on the nameplate
• For 25 years as of the pr
least 80 % of the nominal power indicated on the nameplate
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. Dur
this 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.
For 12 years as of the production date a performance of a PV
least 90 % of the nominal power indicated on the nameplate
For 18 years as of the production date a performance of a PV
least 85 % of the nominal power indicated on the nameplate
For 25 years as of the production date a performance of a PV
least 80 % of the nominal power indicated on the nameplate
6. What are the performance bank guarantees taken from the suppliers and for how
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
For 18 years as of the production date a performance of a PV-module of at
oduction date a performance of a PV-module of at

21. 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
guarantee). In most cases this means a guaranteed electrical production for 10
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:
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
This means SunPower guarantees 87% of rated power output at
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 1: Solar Panel Warranty Comparison
The majority of solar panels on today`s
year long warranty (also known as a performance
guarantee). In most cases this means a guaranteed electrical production for 10
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
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
This means SunPower guarantees 87% of rated power output at
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)

22. • 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.
A module design shall be judged to have passed the qualification test,and therefore to
approved if each sample meet the following criteria:
The degradation of the maximum power output at standard conditions (STC)
does not exceed 5% after each test nor 8% after each test sequence;
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
A module design shall be judged to have passed the qualification test,and therefore to
The degradation of the maximum power output at standard conditions (STC)
does not exceed 5% after each test nor 8% after each test sequence;
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

23. Code Qualification test Test description /Pass criteria
10.1 Visual Inspection according defined inspect
10.2 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 ir
according to IEC 60904
10.6 Performance at
NOCT
Cell temperature = NOCT
irradiance 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 worst
spot condition
10.10 UV-Exposure
according IEC UV-
61345
7,5 kWh/m² UV
radiation (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/m
within 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
Determination of the temperature coefficients of short circuit
current Coefficients and open circuit voltage in a 40°C interval
Total solar irradiance = 800 W/m² , Spectral irradiance distribu
according 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 60904
60 kWh/m² solar irradiation
5 one hour exposures to 1000 W/m² irradiance in worst
spot condition
7,5 kWh/m² UV-radiation (280 - 320 nm and ≥15 kWh/m
radiation (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
Determination of the temperature coefficients of short circuit
current Coefficients and open circuit voltage in a 40°C interval
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.

24. 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
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 peak output wattage is more than 90 % in first ten years and more
than 80 % at the end of 25th year
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
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
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 +/
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
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
diodes is functioning, the diode function should be checked on each new module
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.
to ensure peak output wattage is more than 90 % in first ten years and more
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
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
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
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
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
diodes is functioning, the diode function should be checked on each new module
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

25. 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
follow specific design rules that forbid the attachment of conductive mounting
hardware directly onto polymeric back-sheets behind solar cells and/or other
components of the electric circuit. Module framing should be mounted outside of the
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
follow specific design rules that forbid the attachment of conductive mounting
d solar cells and/or other
components of the electric circuit. Module framing should be mounted outside of the
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.

26. 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.

27. 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

28. 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

29. 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
performance warranty:
• For 5 years as of the production date
95 % of the nominal power indicated on the nameplate.
• For 12 years as of the production date a performance of a PV
least 90 % of the nominal power indicated on the nameplate
• For 18 years as of the
least 85 % of the nominal power indicated on the nameplate
• For 25 years as of the production date a performance of a PV
least 80 % of the nominal power indicated on the nameplate
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
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
term warranties for their products. Some of the warranties provided by PV
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.
In a warranty case 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
the company at the time of the warranty case, company retains the right to supply
a functionally identical PV-module of the same or higher capacity of a diffe
type. The remaining period of the original warranty period applies to newly
Performance warranty
warrants for every PV-module as a voluntary,
performance warranty:
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.
For 12 years as of the production date a performance of a PV
least 90 % of the nominal power indicated on the nameplate
For 18 years as of the production date a performance of a PV
least 85 % of the nominal power indicated on the nameplate
For 25 years as of the production date a performance of a PV
least 80 % 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
the company at the time of the warranty case, company retains the right to supply
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
term warranties for their products. Some of the warranties provided by PV
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
the company at the time of the warranty case, company retains the right to supply
-module of the same or higher capacity of a different
type. The remaining period of the original warranty period applies to newly
-module as a voluntary, independent
-module of at least
For 12 years as of the production date a performance of a PV-module of at
date a performance of a PV-module of at
For 25 years as of the production 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

30. type. The remaining period of the original warranty period applies to newly
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/project
b) Machinery Breakdown
c) Force Majeure
d) Risk
There are several insurance
due to non generation of the plant
All risk policy, including Loss of Income and Reduced yield cover
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.
type. The remaining period of the original warranty period applies to newly
Generally there are no LD clauses applicable on the module manufacturer. They
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:
All risk policy, including Loss of Income and Reduced yield cover
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
insurer will compensate for the reduced yields, if the prognosticated energy
p.a. accordant with profit survey or profit expertise has fallen short
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.
for single PV-installation only on request and after u
acceptance by the insurer.
type. The remaining period of the original warranty period applies to newly
Generally there are no LD clauses applicable on the module manufacturer. They
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
insurer will compensate for the reduced yields, if the prognosticated energy
or profit expertise has fallen short
The insurer provides a 1 year cover for single installations and a 1 or 5 years
installation only on request and after upfront

31. 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

32. during execution of the contract. Example of claim case
plant 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

33. Appendix
Below are the some of the companies along with the certified tests which are done in that
company.
The following tests conducted by
1. Insulation test
2. Performance at STC and NOCT
3. Performance at low irradiance
4. Outdoor exposure test
5. Hot-spot endurance test
6. UV preconditioning
7. Thermal cycling test
8. Humidity freeze test
9. Damp heat test
10. Robustness of termination test
11. Wet leakage current test
12. Mechanical load test
13. Hail test
14. Bypass diode thermal test
15. Bonding Path Resistance Test
16. Wet Insulation-Resistance Test
17. Terminal Torque Test
18. Impact Test
19. Water Spray Test
20. Accelerated Aging Test
21. Humidity Test
22. Corrosive Atmosphere Test
23. Partial discharge-test MST 15lic Coatin
24. PID Test
25. FTIR spectrometer
26. UV/Visible spectrometer
27. Spectral Ellipsometry
28. LID test.
Appendix
Below are the some of the companies along with the certified tests which are done in that
conducted by Jinco Solar in their production process
Performance at STC and NOCT
Performance at low irradiance
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
Below are the some of the companies along with the certified tests which are done in that
in their production process

34. The following tests conducted by
1. Insulation test
2. Measurement of temperature coefficients
3. Measurement of NOCT
4. Performance at STC and NOCT
5. Performance at low irradiance
6. Outdoor exposure test
7. Hot-spot endurance test
8. UV preconditioning
9. Thermal cycling test
10. Humidity freeze test
11. Damp heat test
12. Robustness of termination test
13. Wet leakage current test
14. Mechanical load test
15. Hail test
16. Bypass diode thermal test
17. Bonding Path Resistance Test
18. Wet Insulation-Resistance Test
19. Terminal Torque Test
20. Impact Test
21. Water Spray Test
22. Accelerated Aging Test
23. Humidity Test
24. Corrosive Atmosphere Test
25. Partial discharge-test MST 15lic Coating Thickness Test
26. PID Test
27. FTIR spectrometer
28. UV/Visible spectrometer
29. Spectral Ellipsometry
30. LID test.
conducted by JA Solar in their production process
Measurement of temperature coefficients
Performance at STC and NOCT
Performance at low irradiance
spot endurance test
Robustness of termination test
Wet leakage current test
rmal test
Bonding Path Resistance Test
Resistance Test
Corrosive Atmosphere Test
test MST 15lic Coating Thickness Test
UV/Visible spectrometer
in their production process

35. The following tests conducted by
1. Insulation test
2. Measurement of temperature coefficients
3. Measurement of NOCT
4. Performance at STC and NOCT
5. Performance at low irradiance
6. Outdoor exposure test
7. Hot-spot endurance test
8. UV preconditioning
9. Thermal cycling test
10. Humidity freeze test
11. Damp heat test
12. Robustness of termination test
13. Wet leakage current test
14. Mechanical load test
15. Hail test
16. Bypass diode thermal test
17. Bonding Path Resistance Test
18. Wet Insulation-Resistance Test
19. Terminal Torque Test
20. Impact Test
21. Water Spray Test
22. Accelerated Aging Test
23. Humidity Test
24. Corrosive Atmosphere Test
25. PID Test
26. FTIR spectrometer
27. Spectral Ellipsometry
28. LID test.
conducted by C Sun in their production process
Measurement of temperature coefficients
Performance at STC and NOCT
Performance at low irradiance
spot endurance test
Robustness of termination test
Wet leakage current test
Bypass diode thermal test
Bonding Path Resistance Test
Resistance Test
Corrosive Atmosphere Test
in their production process

36. The following tests conducted by
1. Insulation test
2. Measurement of temperature coefficients
3. Measurement of NOCT
4. Performance at STC and NOCT
5. Performance at low irradiance
6. UV preconditioning
7. Thermal cycling test
8. Humidity freeze test
9. Damp heat test
10. Wet leakage current test
11. Mechanical load test
12. Bypass diode thermal test
13. Bonding Path Resistance Test
14. Wet Insulation-Resistance Test
15. Terminal Torque Test
16. Impact Test
17. Water Spray Test
18. Accelerated Aging Test
19. Humidity Test
20. FTIR spectrometer
21. UV/Visible spectrometer
22. Photoluminescence spectrometer
23. Spectral Ellipsometry
24. LID test.
conducted by Renesola in their production process
Measurement of temperature coefficients
Performance at STC and NOCT
Performance at low irradiance
Wet leakage current test
Bypass diode thermal test
Bonding Path Resistance Test
Resistance Test
UV/Visible spectrometer
Photoluminescence spectrometer
in their production process