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“By 2030, we hope that every building will have an independent source of green electricity.”

An interview with Stephan Kube, Head of Marketing at Heliatek, a German start-up that has developed flexible, self-adhesive organic solar panels.
“By 2030, we hope that every building will have an independent source of green electricity.”
“By 2030, we hope that every building will have an independent source of green electricity.”

Can you introduce your company in a few words?

We are one of the leaders in organic photovoltaic technology and, above all, the only ones to have successfully developed flexible, self-adhesive solar panels that can be applied like a sticker to almost any type of surface. Our self-adhesive solar films are ultra-light, flexible, ultra-thin and can be easily applied to a variety of materials such as glass, metal and concrete. This means that our products can be installed just about anywhere, especially in places previously considered inaccessible to solar technologies.

Can you tell us more about your solution and explain how it differs from those of your competitors?

It's quite simple! We started from the principle that every building, but also street furniture like bus shelters, should be able to create energy. To achieve this, they simply need to be equipped with voltaic panels. However, this is not always possible because these "architectural objects" sometimes have shapes that are not suitable for the purpose. In addition, their structure is not always strong enough to support the weight of conventional solar panels, which can reach 25 kg per m², as they sometimes need to be equipped with cooling systems. Our technology makes it possible to remove all these obstacles since we have succeeded in depositing photovoltaic cells composed of carbon nano-molecules on a self-adhesive film composed of various polymers. This film must meet certain specific requirements: strength, UV protection, waterproofing, ease of cutting and integration into our manufacturing process, etc. In view of these characteristics, we turned essentially to polymers because they tick all the boxes.

I won't mention the nature of the polymers or the assembly processes, or the production tools we have developed, as these are all manufacturing secrets that are the subject of more than 300 patents. In the end, all the organic layers are only a few hundred nanometres thick and are protected by several plastic protective films. This sandwich results in a thin, flexible and light solar film that weighs around 1 kg per m².






What benefits does your technology offer?

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Our solar panels are made up of strips of flexible, self-adhesive plastic film of varying lengths. They can therefore be placed anywhere and on any surface. They are almost ready to use. I'm hardly exaggerating when I say that all you have to do is stick a strip on a bus shelter, for example, and connect it to a lamp to make it energy self-sufficient. Installation time is also a major asset. It takes approximately 2 minutes to apply a 5-metre strip. The most time-consuming part of the process involves cleaning the receiving surface thoroughly to ensure proper adhesion of our sticker and plotting out the markings. Finally, these films are translucent, so they can be applied to windows while still allowing light to pass through to maintain access to natural light.


Can you tell us about the most significant pilot projects you have carried out around the world?

These projects have allowed us to test our technology in real life in different climatic conditions and on different materials. This is how we have further improved our solutions. One example is a school in France, which was our first large-scale deployment in 2017, when we installed 530m² of photovoltaic film to cover almost 20% of the site's consumption. In Spain, our panels were installed on wind turbine masts. Finally, our solution is also of interest to warehouse managers because it is very easy to install them on metal façade cladding.
Since 2014, organic solar films have been successfully used in around 30 pilot installations in Germany, China, Singapore, France, Belgium and Egypt. The pilot projects have been carried out on building materials such as glass, concrete, aluminium and polymer membranes.

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Some people think of polymers as just polluting materials, but they are essential in your industry. What is your environmental policy?

What happens to your products when they reach the end of their life? Polymers or plastics are indeed part of our daily lives. We use them to produce solar films that produce green energy.
We believe that we are actively participating in the development of new clean and renewable energy sources that replace fossil fuels. With a carbon footprint of less than 10g CO2/kWh, our solar technology is one of the greenest of all solar technologies, as it does not require silicon. Thanks to polymers, in particular, the energy linked to production pays for itself in less than 6 months of use of our panels and we estimate that it takes less than 3 months to neutralise the carbon emitted. Then, after these 6 months, our solutions produce green energy for the 20-year lifespan of the panels. It goes without saying that our environmental balance sheet is largely positive since we are participating in the decarbonisation of electricity networks. Of course, we also include the use of polymers in this balance sheet.
For the end-of-life treatment of our panels, we are currently evaluating two options.



Of course, we are looking for ways to recycle them, but the chosen technique must be reasonable from both an ecological and economic point of view. Incineration is the other option and this one seems quite interesting to us. Indeed, the energy recovery could allow us to produce electricity again and would be neutral since the incineration of our products does not create toxic substances.


Moreover, our films do not contain any rare or precious materials. Incinerating them to recover energy would therefore make sense. For the time being, nothing has been decided as these two solutions for the end-of-life treatment of our films are still being tested.


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