Site IV.7

Health
COD
2015
Nominal Capacity
20 kWp
Yield since COD
1041 kWh/kWp
Possible Gain
12% to 18%
CAPEX, OPEX
2.5 ₹/Wp, 0.3 ₹/Wp/a

Abstract

The PV plant is affected by nearby shading from trees and roof structures. The electroluminescence investigation showed some micro cracks and isolated parts. Furthermore, the DC wiring is not installed correctly. It is recommended to (i) replace the broken modules, (ii) increase the cleaning frequency, (iii) replace modules exceeding the manufacturer’s guaranteed performance drop and (iv) fix shading problems. The estimated production boost caused by the retrofitting actions lies between 12-18%.

Image gallery

Main Findings

The system grounding is not installed securely.
String cables damaged by or in contact with sharp edges were spotted.
The cables of the irradiation sensor are not installed correctly.
The connectors of the string cables at the inverter are not correctly attached.
Some cables are insulated with duct tape.
Cable ties broke, hence the module cables and connectors are loosely hanging.
The bending radius of the string cables is respected only partially.
Some parts of the cables are exposed to UV radiation. And some cable ducts have already broken.
Some of the labels detach from the modules.
In some places, the string cables are combined in cable bundles that heat up.

Impact on Performance

Soiling

Soiling leads to a power loss of 2% on system level. Additionally several hot spots were discovered in the plant due to the soiling.

Estimated Loss
≈ 2%
Cell Cracks

Based on the amount of cracks and broken cells and corresponding inactive areas, the power loss is estimated to be 5% at the system level.

Estimated Loss
≈ 5%
Near Shading

Near shading is caused from nearby trees on the South side of the plant and installed antennas on the roof. The simulation of the system showed a shading loss of 5.9%.

Estimated Loss
≈ 5.9%
Total Estimated Energy Loss
≈ 12.9%

Proposed Solutions

All DC wiring should be maintained.
The cleaning frequency should be increased and the strong local contamination should be removed.
PV modules showing power drops above the warranty conditions should be replaced.
The shading caused by trees or roof structures should be mitigated.
Broken modules shall be immediately replaced.
Module product defects (detached labels) shall be monitored, whether the degradation continues (potential claim) or it has stabilized.
The grounding of the entire system should be checked.