Life expectancy of photovoltaic solar panels

[Christophe]

Predict the life expectancy of solar panels

Solar panels are exposed to various environmental conditions, which degrade the material over the years. Researchers at the Fraunhofer Institute for Materials Mechanics (IWM) in Freiburg im Breisgau (Baden-Württemberg) have developed a method by which the effect of these influences can be calculated over the long term. This allows reliable predictions of panel life.

Although most panel manufacturers provide their customers with a warranty of up to 25 years, they themselves cannot reliably judge the expected life of the panels. To be authorized for operation, solar modules must indeed meet certain standards. For this, they are exposed to high temperatures or heavy mechanical loads in different experiments. "However, the results only indicate the robustness of a new specimen against extreme short-term loads. To determine the actual life, age-related effects such as material fatigue are on the contrary relevant, and they only occur over time, ”explains Alexander Fromm of the Fraunhofer Institute IWM.

Scientists at the IWM are working, within the framework of the project "Reliability of photovoltaic modules II" funded by the Federal Ministry of the Environment (BMU), on a new method for predicting the lifespan of solar modules. "With our two-pronged principle, we combine actual measurement data with digital simulation," explains Fromm. To do this, scientists are first studying in the field the impact of mechanical stress on the installation. Indeed, the weight of the snow, the temperature variations and the gusts of wind generate mechanical stresses or deformations in the panels. This leads in the long term to material fatigue. Plastic-based potting material and especially cell connectors (thin strips of copper with which solar cells are bonded together) are particularly sensitive.

In order to understand the factors that influence the material, the researchers equipped a complete solar module with sensors measuring, through the variations of resistance, the deformations on the surface of the components. Then, the mechanical stresses of the material could be calculated. During the evaluation, the scientists discovered that even a light wind is enough to generate a vibration in the module. This vibration is all the more pronounced as the ambient temperature is high. In addition, the oscillation frequency increases over time, because the plastic becomes, under the action of UV radiation, more rigid and brittle.

Subsequently, a detailed 3D simulation model was developed for the solar module. Based on the field measurement results, inferences using numerical calculations are made to explain how environmental influences impact the module components in the long term, and what mechanical stresses occur in the material. "For example, we found through simulation that UV-induced embrittlement plays a much larger role in material fatigue than we thought," says Fromm. In order to predict the life of a module, researchers combine field measurements with known characteristic strength values ​​of the corresponding materials. These figures illustrate from what degree of stress the material is likely to break or come loose.

The process is ready for use today. To create optimal and reliable predictions, however, developers need as detailed material data as possible, as well as information about the geometry of the module under test. "Our method does not offer a mass test, but on the contrary is tailored to each client," explains Fromm. Based on their calculations, the researchers can then not only draw conclusions about the expected service life, but also highlight potential for improvement in terms of geometry and material. Finally, these results make it possible to study the different materials and the mechanical stresses characteristic of each of them in the module.

http://www.bulletins-electroniques.com/ ... /74063.htm

Via: http://www.isolation-chauffage.com/nouv ... 2/#msg5342

[swallowtail]

good evening christophe

interesting approach, and very "conventional".

I can just say that I had PV that dated 1988 env, more than 25 years old and still produced, despite harsh living conditions: sea air, spray, violent wind, live, heat and equatorial pacific humidity, and destructive UV at these latitudes.

I think that by doing research and testing in collaboration with antities possessing old PV (individuals, companies, public bodies), we should quickly and easily obtain data allowing to appreciate a lifespan "in condition", more easily than through "computer modeling"?
But this on old material, (maybe + robust?) Not benefiting from the last evolutions of the materials !!

swallowtail

[moinsdewatt]

Sometimes it's not the end of life expectancy:

Fire on the roof of a large Apple building (in Arizona) that included solar panels, and partial collapse of the roof.
The investigation will look for if it is the solar installation which made start the fire.

Solar panels on Apple plant in Arizona catch fire

27 May 2015

Firefighters Responded to an emergency at Apple's facilities in Mesa, Arizona on Tuesday afternoon after a blaze broke out in an area of ​​solar panels fitted to the roof of the building.

According to local news reports, firefighters identified that the fire erupting on the 12-hecatare site was located only on a section of the roof overlooking a loading dock.

While around 50 people were forced to evacuate the building, 100's firefighters were able to get under control in about 30 minutes, though a portion of the roof collapsed.

News reports noted that fire investigators are trying to find out if The fire was a direct result of the solar panels located on the roof.

The facility features a lengthy history. First Solar was the original owner of the building, eventually selling it to Apple in 2012. Apple then leased to GT Advanced Technologies (GTAT) in order to use the space as a factory to manufacture sapphire screens for handheld devices.

Ultimately, the sapphire-screen factory plans never came to fruition, as GTAT eventually filed for bankruptcy last year. As a result, Apple shifted the building's purpose of a data center, touting its green credentials

http://www.pv-tech.org/news/solar_panel ... catch_fire


http://www.macrumors.com/2015/05/26/app ... ches-fire/

[elephant]

On the fire, not excluded: when we see the beautiful arches that we can draw .... and if the roof is made of bituminous materials ....

Over the lifetime: I think that if it was short, we would not have sent as much in space ... and when I see some of my plants in service for more than 30 years (24h / 24 service) ), I do not worry too much!

[daimebag]

Ben in space, you have no wind, no humidity, no atmosphere, so what's more normal ...

[Forhorse]

But you have UV (A, B and even C) in shambles, rays (X, gamma, and so on) the extreme temperatures etc ...
I doubt it is any more "cool" for the panels than on earth.

[izentrop]

But you have UV (A, B and even C) in shambles, rays (X, gamma, and so on) the extreme temperatures etc ...
I doubt it is any more "cool" for the panels than on earth.

Ionizing radiation in general, cosmic rays being the most energetic and fortunately filtered by the Earth's atmosphere http://www.astrosurf.com/luxorion/satel ... llance.htm

[Forhorse]

Otherwise mine died after 6 years of good and loyal service. The death is ... at a fall of 2m high, oops!
This is what happens when you say to yourself "I'll fix them later"

The bursting glass in a thousand pieces of a piece like that of a car windshield.
So someone knows what you do with an HS PV panel? they take them to the dump?

[moinsdewatt]

Otherwise mine died after 6 years of good and loyal service. The death is ... at a fall of 2m high, oops!
This is what happens when you say to yourself "I'll fix them later"

The bursting glass in a thousand pieces of a piece like that of a car windshield.
So someone knows what you do with an HS PV panel? they take them to the dump?

the adhoc organization is PVcycle.

read: http://www.pvcycle.org/wp-content/uploa ... _web_2.pdf

[Forhorse]

Super, the nearest collection point is at 65Km from home
In addition, as a bonus it is a dump, great chance that the caretaker knows nothing and push me to the entrance because I am not a resident of the area served.