Embed Size (px)
Citation preview
powered byWebinar
Lou Trippel
First Solar
Mark HutchinsTristan Erion-Lorico Anil Kottantharayil
Quantify the impacts of
cell cracking in the field25 May 2020
4 PM – 5 PM10 AM – 11 AM 7.30 PM – 8.30 PM
| CEST, Berlin| EDT, New York| IST, India
Prakash Suratkar
PV Diagnostics
PVDiagnosticsPrivate and Confidential
Team of IIT Bombay graduates &
Industry Veterans
PV Diagnostics offers diagnostics and quality control solutions for solar power plants
2
Procurement 3rd party factory inspection of modules
Post TransportationEL image based quality check to identify transportation damages; Insurance support
Post InstallationPost commissioning study; PR Test; Technical supervision during installation
Diagnostics
Technical Due Diligence
Health check-up of the plant for risk assessment, performance prediction
We provide On-site testing and technical support through solar value chainAbout us
Health check-up of plant; performance improvement strategy
2500+ MWp of diagnostics
Experts in module tech, design and
operations
Focus on performance improvement
PVDiagnosticsPrivate and Confidential
Our portfolio: 2500+ MWp of diagnostics across country in 2 years
3
Clients On-board
PVDiagnosticsPrivate and Confidential
Higher degradation rates and defected modules emphasize on the need for such measures…
4Charts are based on actual measurements taken by the PVD team for multiple plants across the country in year 2017-18; Potential error of 2-3% due to onsite measurement
0% 2% 4% 6% 8% 10% 12% 14% 16% 18%
UP - 2 years old
Gujarat - 6 years old
MP - 5 years old
Rajasthan - 5 years old
0% 2% 4% 6% 8% 10% 12% 14% 16% 18%
Maharashtra - 2 years old
Maharashtra - 7 years old
Underperformance in plants across the country Module level defects indicate poor quality control
~30%
~22% ~7%
Modules with Cracks
Modules with PID
Modules with Soldering Defects
~30%
~1% ~3%
Modules with Cracks
Modules with PID
Modules with Soldering Defects
Uti
lity
Scal
eR
oo
fto
p p
lan
ts
PVDiagnosticsPrivate and Confidential
Types of Cracks-I
5
Partial Crack
Full Crack
PVDiagnosticsPrivate and Confidential
Type of cracks-II
6
Spider Crack
Compound Crack
PVDiagnosticsPrivate and Confidential
Thermal, EL and visual image of module with cracks
7
PVDiagnosticsPrivate and Confidential
Hotspot generation due to cracks
8
Example of crack leading to hotspot and burning
PVDiagnosticsPrivate and Confidential
Case StudiesKey observations and results
PVDiagnosticsPrivate and Confidential
Case Study 1 – Post transportation module inspection
10
Module with
cracks
• Plant size: 1 MW
• Location: Rajasthan
• Status: Client suspected that modules were damaged during transportation
• 18% modules had wafer defects and edge isolation
• 6% modules had severe edge isolation
• 7% modules had micro cracks
• 14% modules had partial, full, compound or point cracks
• Modules were identified to be replaced by the manufacturer
• Certain modules were identified to be kept under close monitoring as they could lead to hotspots which would be a reliability and safety concern
Plant details Defect categorization found in modules Results from the study
Wafer defects
Edge isolation
PVDiagnosticsPrivate and Confidential
Case study 2 – Post transportation and post installation damage analysis of modules
2.1%
8.5%
2.1%
22.1%
0.0%
5.0%
10.0%
15.0%
20.0%
25.0%
Soldering Issue Cracks
Modules with defect (%)
Post Transportation Post Installation
Inspection stage Sample sizeSoldering Issue Cracks
No. % No. %
Post Transportation 340 7 2.1% 29 8.5%
Post Installation 140 3 2.1% 31 22.1%
Plant Details
• 50 MWp plant in Tamil Nadu, study conducted for a 5 MW batch
Observations
• 3 modules were severely damaged post-transportation and rejected
• ~2.1% modules had slight solder contact issue, which can be taken up with module manufacturer
• 8 out of 34 (23.5%) corner modules in pallets were damaged. This implies that pallets placed next to the container walls were not packed properly
• ~8.5% modules had some form of cracks (partial, full, compound or point/spider crack) in post transportation study, but ~22% modules has cracks during post installation study
Recommendations
• We strongly recommend getting EL Images of selected sample from the module manufacturer to establish accountability
• Training of ground staff for better handling of modules
• Lot rejection criteria should be setup with the manufacturer based on module quality
PVDiagnosticsPrivate and Confidential
Key TakeAway
• In most of the solar plants in India cracks are observed in the modules and these cracks are of different severity. The percentage of cracks can be as high as 30%
• Cracks can develop during transportation and/or during commissioning. Therefore its important to study few select modules by taking its El image: a) after transportation b) after commissioning
• Its important to keep the track of cracks being developed over period of time by including periodic El imaging of the modules. This can be done as part of regular O& M practices
• Though clear relationship is not established, cracks with along other defects such as solder failure, PID can contribute to module degradation
12
