Why Aviation Know-How Pushes PV-Modules to New Levels

The following article covers an interview with Mr. Matthias Schoft, managing director of DAS Energy GmbH, a joint venture of Alternative Energy Solutions and Diamond Aircraft Group. DAS Energy GmbH is an innovative, ambitious company based in Austria, which sparked international attention developing and producing non-glass photovoltaic modules.

DAS Energy GmbH is quite an interesting cross-industry joint venture between a world-leading airplane company and a company specialized in the photovoltaic service industry. What have been the major drivers to set-up this business constellation?
The motivation behind joining forces originated in the drive of both companies to innovate and bring new as well as ambitious ideas to the market. Throughout the shared know-how, DAS Energy was able to create a discerning idea: Instead of glass, DAS Energy uses glass-reinforced plastic in their modules, which is normally used in aircraft construction of Diamond Aircraft Industries. Of course, the investment in this new production was preceded by several years of research and the development marketable and innovative photovoltaic modules of this new type.

What is the superior value in module manufacturing when teaming-up with an aviation company?
Based on the extensive know how of the Diamond Aircraft group relating to compound materials and lightweight constructions, we were able to produce a flexible and very light module – weighting only 2,5 kg per square meter. This means that our modules weight half of other comparable flexible modules and about an eighth of a regular commercial photovoltaic module.
The weight and stability advantages of our modules mainly root in the selection of the core material comprised of glass-fiber and reinforced plastic called prepreg. The reinforced plastic layer is situated over and under the cells and is responsible for the flexibility and adds to the stability of the module.

Is it only the weight-effect, which allows your company to differentiate from competitors?
On the one hand I would say yes. Our light-weight modules allow for multiple application modes in modern architecture or mobile applications as caravans, boats, golf carts etc. On the other hand, we have the additional advantage that our modules have a higher power yield than regular photovoltaic modules. Due to no glass being used on top of the cells the heat dissipation on the front side of the cell is very efficient. The used material of the module is already very heat resistant and a special “Desert Module” is under development at the moment, which will be an upgrade of our standard module. Heat has the same negative effects on all crystalline modules resulting in less efficiency, but the technology behind the DAS Module prevents damage caused by heat. A further alternation of the “Desert Module” will be adaptions to harsh weather conditions. Making it “sandstorm resistant” will add an additional advantage compared to conventional modules, which cannot resist sandstorms frequently without suffering damage to their back sheets.

Which technological advances make DAS Energy modules better equipped to withstand negative environmental impacts?
Our product successfully passed the IEC tests including temperature tests with cycles from -40 to + 85°C.
The front foil of our module is called ETFE which stands for Ethylene tetrafluoroethylene. This material is widely used by architects and is a very dirt resistant material. An example where ETFE is used is the Allianz Arena Munich, home of the famous soccer club Bayern München. Due to the use of this high-tech-material, the modules can be installed on flat roofs with a very low inclination and DAS modules are “hail-resistant”.

Another issue we tackled, is the impact of irradiation, heat, and humidity over longer periods of time, which can lead to decreasing material performance.
DAS Energy uses the harshest tests available to simulate different weather and environmental conditions, for example the Xenon Test Chamber. This particular test was originally developed for the automotive industry to test the impact of irradiation on car paint. Different parameters like transparency, yellowing and glance are measured after the test chamber and are then compared to the original values. DAS Energy modules more than fulfill the requirements (50-60 years Central Europe and 10-12 years Florida.) even after much more test cycles than required. As a consequence we can insure a long-lasting and very productive product.

Having in mind that you are already roughing up the PV module market with your product, what is on your agenda for the mid-term? (2016/2017/2018)
In 2016 and 2017 the company plans to enter new markets focusing on Turkey, India, and the Middle East. Entering new markets includes the construction of new factories to act more locally. On the long run, our future vision is that as – within the bounds of the humanly possible – no building is planned, built, or renovated without an individual energy supply. Additionally, the increasingly mobile applications should also use the free energy of the sun.[/vc_column][/vc_row]