Pleasantly sustainable: green façades with coloured solar panels
Pleasantly sustainable: green façades with coloured solar panels

Pleasantly sustainable: green façades with coloured solar panels

You see them on old roofs and new roofs, on business premises and government buildings; solar panels are everywhere. But now that the Nearly Zero-energy Buildings (in Dutch: BENG-3 legislation requires new buildings to generate at least 40% of their own energy consumption, solar roof panels no longer offer an adequate solution. The innovative start-up Soluxa has combined necessity with aesthetics, resulting in coloured solar panels that can be used on building façades. Soluxa completed their first pilot project this summer which involved the installation of a solar façade on the Faculty of Science’s Huygens Building on the Radboud University campus. And their creativity did not go unnoticed: Soluxa was crowned the 2021 winner of the Jan Terlouw Ambition Prize! If you are curious about how Soluxa makes their panels and the benefits that these solar façades provide, read on to find out what founder Lourens van Dijk had to say.

The government’s objective is to generate as much energy as possible within built-up areas. When it comes to new builds, you are even obliged to generate almost half of your own energy. This got Lourens thinking about how he could contribute to making the built environment even more sustainable. During his PhD research in 2015, he investigated the use of light trapping techniques in solar panels. This gave him an idea: “Back then, I was already working on a new technique for coloured solar panels, which could not only be used to make buildings more sustainable, but would also contribute to their charm.” In 2018, Lourens consequently conducted a feasibility study with John Schermer’s Applied Materials Science research group at Radboud University. He was curious to find out just how efficient coloured solar panels were in comparison to the better-known black panels. He not only wanted to know whether there was a demand for coloured panels, but was also keen to find out whether it would be cost effective to build a business case.

Feasible and cost effective

His idea proved to be both feasible and cost effective. He decided to implement it as soon as possible and continued to develop the coating on the basis of nanotechnology and the development of the production process. “And that’s what we’re doing right now. One of the components of this phase is our pilot project, which involved the installation of a solar façade on the Huygens Building at the Radboud University campus. This will be our showcase; it will show potential customers what our product looks like and the types of colours that can be used. If it’s successful, we’d like to explore the option of making the entire Radboud University campus more sustainable, which would include the installation of a solar façade on the 88-metre-high Erasmus building. Now there’s a real challenge!”


Economical, efficient and attractive

Solar panels have become considerably cheaper in the last couple of years, which offers more scope in the application possibilities. In addition to efficiency, the appearance of a panel and its contribution to the face of the building or the environment is now also being taken into consideration. According to Lourens, the trick is to make the panel look colourful while retaining as much efficiency as possible. “At Soluxa, we achieve this by using the Vibrant colour technique. This is a coating that is used to colour conventional black solar panels. The technique is based on nanotechnology, which means that the colour can be adjusted as required.” The coloured panels have an efficiency of 80-98% compared to black panels and therefore offer the option of complying with the new BENG-3 legislation. This means that the panels are not only attractive, but also extremely efficient!

Peak load is obsolete

Solar façades have an additional advantage: they can help to prevent peak loads on an electricity grid. A peak load occurs around midday, because solar panels are normally south-facing. This overloads the grid, although it runs out of energy in the morning and evening when we’re actually using it. According to Lourens, there is a way to counteract this problem: “Solar façades that face east and west can help to prevent peak loads, because they actually catch the sun in both the morning and evening. If you combine these with roof panels, you can create a broad energy profile that is better suited to the usage profile. This means that you can get by with a smaller power plan or that you can feed the generated energy back into the grid without overloading the grid.”

Smart production

Some solar companies set up a completely new production line for manufacturing coloured solar panels. This can be relatively expensive, because requests can often be quite specific and the volume that is produced is not always so high. Soluxa has a simple solution to this problem: “We modify existing standard solar panels by applying a nano-coating so that the panels acquire the desired colour.” This process allows Soluxa them directly follow the improvements of solar panels. “This enables us to keep our product interesting and make it affordable, which is obviously a good business case for any company! At the moment, we’re only working on façade applications, but the possibilities are endless! For example, think of dykes, noise barriers and solar farms.”


High ambitions for the façades

Soluxa’s ambition is to install 500,000 m2 of solar façade in the Netherlands by 2025; which is still just an extremely small fraction of the total available façade area. According to Lourens, this is a realistic goal because, compared to traditional cladding, the additional costs that are associated with solar panels pay for themselves within a few years. “The initial investment in a solar façade is obviously greater, but it does ensure a return. Once companies realise that a solar façade is actually cheaper than traditional cladding, this market is going to really flourish. That means that it’s a smart option for new builds and façades that are in need of renovation.”

Soluxa’s current team is still small, but they are growing rapidly. They are currently working with a number of different partners and are also participating in the Startup in Residence programme in the province of Overijssel. It is through this programme that they will implement solar façades on both the Overijssel provincial government building and the municipal offices in Zwolle. “We continue to learn new things from every project that we carry out. Every building is different and each one requires a customised approach. We are currently streamlining this work process and, as a result, we’re producing wonderful examples that show that Soluxa can offer customised solutions for any building!”

Beneficial for nature conservation

Soluxa’s solution is both extremely sustainable and beneficial for wildlife conservation. Solar panels are becoming cheaper and cheaper, and this means that people are not only covering their entire roofs with panels, but that many solar parks are also being built. “Soluxa is present in the capillaries of the electricity network, close to the end user. This means that the grid does not need to be reinforced. In short: the more solar panels we make, the fewer the number of natural habitats that will be ‘lost’ to developments like solar parks. And that is an ideally sustainable win-win situation!”

This article appeared earlier, in Dutch, on Into Nijmegen. Photo of Lourens van Dijk at the Huygens building, Radboud University: Erik van 't Hullenaar via TechGelderland. Header photo via Soluxa.

Contact information

Organizational unit
Applied Materials Science
Sustainability, Innovation, Molecules and materials