Eva Discoloration Solar Panels

For glass glass module constructions this eva discoloration is more spatially uniform.

Eva discoloration solar panels.

Ethylene vinyl acetate eva encapsulants for photovoltaic modules. The thermal ageing of an ethylene vinyl acetate eva polymer used as an adhesive and encapsulant in a photovoltaic module has been investigated. Pern center for performance engineering and reliability national renewable energy laboratory nrel 1617 cole blvd golden colorado 80401 usa. Discoloration is rarely observed in the eva between neighboring solar cells.

A new non destructive method has been proposed by researchers in india who say identifying early stage discoloration in eva encapsulants can help detect degradation in solar panels before power. Solar panel discolouration is an uncontrolled chemical reaction amongst materials. Eva is the abbreviation for ethylene vinyl acetate. Degradation and discoloration mechanisms and formulation modifications for improved photostability f.

Let s try to make it as simple as possible. However discolored eva encapsulant is reported to cause a loss of light transmission to the solar cells leading to loss in power production by up to 0 5 a year by average 28 or up to 1 a year in subtropical climates 160 and this loss can be as high as. To investigate the eva encapsulant photobleaching and discoloration solar cell laminates having different eva films uv transparent t uv cut c and combination of the two tc were tested. The eva is used to bond the silicon solar cells to the front glass and backing sheet and to protect the photovoltaic materials from the environment and mechanical damage.

The iit bombay group used an ultraviolet accelerated aging test during 34 days on three encapsulant samples. Essentially an acetic acid formation is the problem but not too blame. Discoloration itself may not be directly related to power performance of pv modules. We ll get to that part.

There are plenty of studies online that have fully confirmed that the acetic acid formation is the specific root cause for the discoloration of the eva encapsulate. Very much what appears to be a visual failure discolouration or browning occurs when there is a yellow or brown discolouration of the ethyl vinyl acetate eva a result of two main causes. In the solar industry the most common encapsulation is with cross linkable ethylene vinyl acetate eva. What are ethylene vinyl acetate eva films.

Bad effects of eva browning. With the help of a lamination machine the cells are laminated between films of eva in a vacuum which is under. Browning in pv modules can induce a power loss by up to 0 5 year.