Delamination is a loss of adhesion between the layers of a module, such as glass, encapsulant, cells and backsheet. Its main causes are poor raw materials, manufacturing problems and exposure to heat, UV and moisture in service. Transport and installation do not cause it. The air gaps reflect more light, which lowers module current and power. A large mismatch can switch on bypass diodes. Delamination also lets moisture in more quickly, which can lead to corrosion of metal contacts. Delamination near the edge or the junction box is a safety risk, because it can cause insulation faults, leakage currents or a loose junction box. It is usually easy to see during a visual inspection from the front. Thermography can find delamination that is not visible, and insulation testing only flags severe cases. Replace modules that have lost insulation resistance or electrical safety, or that have an active bypass diode. Monitor the rest with regular visual inspections and ground fault detection.
caused_byc1 drafted · lead Low-quality material
Raw material quality is named as a main origin; transport and installation are said not to cause delamination.
sec=3.1.2 h=0db875b1c7c0sec=1.2 h=00007ee51ba7c2 drafted · lead Manufacturing defect
Includes the manufacturing process, contamination such as poorly cleaned glass, and too-short lamination times.
sec=3.1.2 h=0db875b1c7c0sec=1.2 h=00007ee51ba7sec=6.1.1 h=bc3b4163c337sec=h60 h=6cc7189f11a4c3 drafted · lead Moisture exposure
sec=6.1.1 h=bc3b4163c337sec=2.3.2 h=5147bca98d09sec=h60 h=6cc7189f11a4c4 verified · fact High operating temperature
Debond growth speeds up sharply with higher temperature and humidity.
sec=6.1.1 h=bc3b4163c337sec=2.3.2 h=5147bca98d09verified by: joshuahamsaverified on: 2026-10-20
c5 drafted · lead UV exposure
sec=6.1.1 h=bc3b4163c337sec=2.3.2 h=5147bca98d09sec=h60 h=6cc7189f11a4c6 drafted · lead Mechanical stress
Residual thermal stresses at the interface and external mechanical loads on the module.
sec=2.3.2 h=5147bca98d09sec=h60 h=6cc7189f11a4affectsc7 drafted · lead Module front glass
sec=6.1.1 h=bc3b4163c337sec=2.3.2 h=5147bca98d09c8 drafted · lead Solar cell
The cell/EVA interface may be more prone to delamination than the EVA/glass interface.
sec=6.1.1 h=bc3b4163c337sec=2.3.2 h=5147bca98d09c9 verified · fact Encapsulant
sec=3.1.2 h=0db875b1c7c0sec=6.1.1 h=bc3b4163c337sec=2.3.2 h=5147bca98d09verified by: joshuahamsaverified on: 2026-10-20
sec=6.1.1 h=bc3b4163c337sec=2.3.2 h=5147bca98d09sec=h60 h=6cc7189f11a4verified by: joshuahamsaverified on: 2026-10-20
c11 drafted · lead Cell interconnect ribbon
sec=2.3.2 h=5147bca98d09c12 drafted · lead Junction box
Delamination near the junction box can loosen it.
sec=h6 h=9e4d1b1adbd8tbl=17.r3 h=b816426a98a2tbl=36.r3 h=b816426a98a2sec=h60 h=6cc7189f11a4presents_asc13 drafted · lead Visible delamination
sec=3.1.2 h=0db875b1c7c0sec=1.2 h=00007ee51ba7sec=6.1.1 h=bc3b4163c337c14 drafted · lead Backsheet bubbles or ripples
Backsheet delamination may look wavy, with bumps, bubbles, ripples or peeled layers.
sec=h60 h=6cc7189f11a4c15 drafted · lead Reduced short-circuit current
Extra reflection at the new air interfaces lowers current.
sec=2.3.2 h=5147bca98d09sec=6.1.1 h=bc3b4163c337c16 drafted · lead Reduced STC output power
sec=2.3.2 h=5147bca98d09c17 drafted · lead Bypassed substring
Severe current mismatch can activate bypass diodes.
sec=3.1.2 h=0db875b1c7c0sec=1.2 h=00007ee51ba7sec=2.3.2 h=5147bca98d09detected_byc18 drafted · lead Visual inspection
sec=3.1.2 h=0db875b1c7c0sec=1.2 h=00007ee51ba7tbl=11.r2 h=3d6e72f20727sec=6.1.1 h=bc3b4163c337c19 drafted · lead Insulation resistance testing
Hints at severe delamination only; not suitable for early detection.
sec=3.1.2 h=0db875b1c7c0sec=1.2 h=00007ee51ba7tbl=11.r2 h=3d6e72f20727c20 verified · fact Infrared thermography
Pulse and lock-in thermography can find delamination that is not visible.
sec=6.1.1 h=bc3b4163c337sec=2.3.2 h=5147bca98d09verified by: joshuahamsaverified on: 2026-10-20
c21 drafted · lead Scanning acoustic microscopy
sec=2.3.2 h=5147bca98d09c22 drafted · lead Ultrasonic scanning
sec=6.1.1 h=bc3b4163c337c23 drafted · lead X-ray tomography
sec=6.1.1 h=bc3b4163c337leads_toc24 drafted · lead Severe Metallization Corrosion
sec=6.1.1 h=bc3b4163c337sec=h6 h=ab4b4f0e5fd4sec=2.3.2 h=5147bca98d09review note: support check: partial - Delamination leads to corrosion of metallic components, but 'severe' metallization corrosion is not specifically stated.
c25 drafted · lead Loss of electrical insulation
sec=3.1.2 h=0db875b1c7c0sec=1.2 h=00007ee51ba7sec=h6 h=9e4d1b1adbd8sec=6.1.1 h=bc3b4163c337sec=h60 h=6cc7189f11a4c26 drafted · lead Leakage current
Most likely when delamination forms a continuous path from the circuit to the module edge.
sec=3.1.2 h=0db875b1c7c0sec=1.2 h=00007ee51ba7c27 drafted · lead Junction Box Failure
sec=h6 h=9e4d1b1adbd8tbl=17.r3 h=b816426a98a2tbl=36.r3 h=b816426a98a2sec=h6 h=9e4d1b1adbd8sec=h60 h=6cc7189f11a4verified by: joshuahamsaverified on: 2026-10-20
mitigated_byc29 drafted · lead Module replacement
Replace modules that lose electrical safety or insulation resistance, or that have an active bypass diode.
sec=3.1.2 h=0db875b1c7c0sec=1.2 h=00007ee51ba7c30 drafted · lead Close monitoring
Watch modules with minor delamination using regular visual inspections and ground fault detection.
sec=3.1.2 h=0db875b1c7c0sec=1.2 h=00007ee51ba7c31 drafted · lead Certified product selection
sec=3.1.2 h=0db875b1c7c0sec=1.2 h=00007ee51ba7typical_power_lossc32 drafted · lead nominal 20 PERCENT
Conditions: Field-deployed EFG-Si module, first 3 years of deployment, with delamination, moisture ingress and contact corrosion (reported as nearly 20%)
sec=2.3.2 h=5147bca98d09review note: support check: partial - Nearly 20% Pmax drop in first 3 years of an EFG-Si module is stated, but it's a single case and 'typical' is not stated.; possible conflict with c34 (same source; check the conditions)
c34 verified · fact nominal 11.5 PERCENT
Conditions: PV system after 12 years of exposure, with loss attributed mainly to cell/encapsulant delamination
sec=2.3.2 h=5147bca98d09verified by: joshuahamsaverified on: 2026-10-20review note: possible conflict with c32 (same source; check the conditions)
current_dropc33 drafted · lead nominal 5 PERCENT
Conditions: Isc drop of the same EFG-Si module over its first 3 years of deployment (reported as about 5%)
sec=2.3.2 h=5147bca98d09related_to c10leads_to c19leads_to c27leads_to c14caused_by c5caused_by c12caused_by c8leads_to c23leads_to c22caused_by c5