79 MW Site

Anomalies Identified

13 Anomalies, 10,967 Modules Affected

Power Loss

3434 kW, 4.37% Affected 

Annual Financial Loss

$184,731 Lost if Anomalies Unresolved

Inspection Summary

This 79 MW PV system was inspected before the annual preemptive maintenance visits. A drone with a thermal camera was flown and photographed every panel in one day. This site was found to be heavily impacted by over 13 types of PV system anomalies, with over 10,000 offline modules. The largest and most impactful issue identified was the 50 inverter faults, amounting to over 4% of annual production loss.

On top of the 50 inverter faults, the inspection identified 8 offline strings which were estimated to reduce production capacity by 84 kW. There were also 64 module level issues and 594 sub-module level anomalies. These reduced the PV system’s production by 95 kW from the site’s full operating capacity.

The operations and maintenance team knew that the site was facing inverter issues due to internal monitoring signals, but the number and location of them were unclear. Upon the report being delivered, the vendor prioritized their onsite task to resolve the various inverter faults causing the 4% daily performance loss. The inspection report equipped them with the data needed to deploy the necessary number of technicians and resources to the affected areas of the PV system.

Anomaly Type Anomaly Amount Modules Affected Est. Affected DC (kW) Est. Affected DC (%) Est. Annual Impact (kWh) Est. Annual Impact ($)
284
284
241
241
3
3
$52
67
67
50
35
35
14
14
$81
8
261

Totals

702

10939

3434 kW

4.37%

7,389,385 kWh

$184,731

This findings table has been filtered to show high priority issues only.

13 MW Site

Anomalies Identified

1884 Anomalies, 2,400 Modules Affected

Power Loss

320 kW, 2.64% Affected 

Annual Financial Loss

$17,427 Lost if Anomalies Unresolved

Inspection Summary

This site was inspected because of underperformance based on recent monitoring signals. Using a drone and thermal imaging camera, the site was flown and data was been uploaded for automated processing to receive an inspection report. The findings uncovered 1,826 anomalies, falling into 9 categories, with 2,400 modules affected. The report identified and located 10 malfunctioning strings, 379 diode faults, and over 400 cases of vegetation across the plant. The annual loss of production from the anomalies identified would total more than 600,000 kWh. 

The PV System manager used the reports and the visual spectrum images from the inspection to assess all 400 cases of vegetation and were able to instruct their vegetation management vendor to the exact locations for removal. The manager also deployed field technicians to investigate the high number of modules affected by diode faults and remediate the 10 string anomalies impacting 0.5% of system performance. Along with this improvement, the PV System manager continued to utilize aerial preventative maintenance inspections regularly to maintain optimal site conditions.

Anomaly Type Anomaly Amount Modules Affected Est. Affected DC (kW) Est. Affected DC (%) Est. Annual Impact (kWh) Est. Annual Impact ($)
457
457
586
586
11
11
379
379
3
3
$50
26
350
10
190
412
412

Totals

1884

2388

320 kW

2.64%

697,301 kWh

$17,427

This findings table has been filtered to show high priority issues only.

5.9 MW Site

Anomalies Identified

442 Anomalies, 2,853 Modules Affected

Power Loss

378.21 kW, 6.56% Affected 

Annual Financial Loss

$17,447 Lost if Anomalies Unresolved

Inspection Summary

This 5.9 MW PV system was inspected as part of an annual preventative maintenance protocol. A drone was flown for three hours and provided the operations and maintenance team with sub-modular anomaly details through thermal and visual spectrum imagery. The inspection showed anomalies from the inverter level down to the cell level. The results uncovered 490 system anomalies, categorized into 16 anomaly types, and amounting to 2,853 affected modules. 

The owner’s operations and maintenance team used the deliverables to identify the most impactful and easily remediated anomalies within the site. The report also enabled them to set up a plan to resolve all non shading related anomalies within two weeks of the site inspection. Next, the new data was used to create a plan to resolve the onsite issues causing the shading and performance loss.

Anomaly Type Anomaly Amount Modules Affected Est. Affected DC (kW) Est. Affected DC (%) Est. Annual Impact (kWh) Est. Annual Impact ($)
37
37
52
324
12
12
$58
12
12
1
1
$9
68
68
257
3
54

Totals

442

2805

378.21 kW

6.56%

698,025 kWh

$17,447

This findings table has been filtered to show high priority issues only.

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