What are microcracks?
Microcracks are tiny hairline cracks in a solar cell that are invisible to the naked eye. Even though you cannot see them, and adverse effects are unlikely to be produced immediately, microcracks are broken solar cells held in place by the solar module laminate. After a time, the solar modules will be affected by various pressures such as bending and flexing, caused by external pressure and fluctuating temperatures. During the day, solar panels expand because of higher temperatures.
Small imperfections in the silicon cell can lead to larger microcracks.
The length of microcracks can vary; some span the whole cell, whereas others appear in only small sections. Microcracks not only lead to significant loss of yield in a solar panel, the performance of panels without microcracks in the same string is also likely to be affected, which consequently affects the lifetime of a solar PV system. When microcracks appear, the shortest path between any point of the cell to the nearest ribbon can be interrupted by the crack, ceasing the flow of electrons. When the electron flow stops, areas of the solar cells become inactive, and the power output suffers.
Potential impacts of microcracks
As the potential impact of microcracks pose quite a serious issue in the long run- it is essential for manufacturers to ensure a good quality control.
Solar cells are very fragile and unless they’re properly protected, microcracks can develop quickly. The chance of microcracks occurring in a glass-glass panel is nil, provided it leaves the factory without them. A manufacturer can verify this with an electroluminescence (EL) test, similar to an X-ray. Solarwatt’s high factory quality standards ensure that any solar panel with microcracks is rejected.
Microcracks in glass-glass panels are covered by Solarwatt’s FullCoverage all-risk insurance
With glass-foil panels, solar cells are much less protected. During transport, installation or, for example, a major hailstorm, microcracks can occur faster. Their effects, however, are not noticed until much later, due to reduced performance following continued deterioration. Microcracks are always outside guarantees provided by manufacturers. Microcracks in glass-glass panels are covered by Solarwatt’s FullCoverage all-risk insurance.