The Solar Cells of Tomorrow Come in All Colours and Patterns

Ugly solar energy systems on roofs are to be a thing of the past. Tomorrow’s solar cells must be integrated in the roof or façade of the buildings so that they are not visible, and they will come in all colours and patterns.

solar cells

If you are considering installing solar cells on your roof—but you are holding back because you do not want a clumsy installation on your house—there is hope ahead. In fact, there are new solutions on the way.

In a new research project, DTU is joining forces with the Danish Technological Institute and a number of enterprises to test and refine a new type of solar cell modules, which are—among other features—to be colourable, so that they can be incorporated in and adapted to the appearance of the individual building.

“One of the things that we’re examining in the project is how the solar cell modules can be coloured without compromising their performance. Energy consumption in buildings accounts for nearly 40 per cent of the total energy consumption in Denmark, and integration of solar cells in building materials is therefore increasingly important in the target to become independent of fossil fuels by 2050,” explains Peter Poulsen from DTU Fotonik, who heads the research part of the new project.

New colouring method
Many different methods for colouring solar cells have already been tested—both in Denmark and internationally. The challenge is that the colouring easily risks reducing the capacity of the solar cells to capture sunlight.

“However, Danish Solar Energy Ltd. has now developed a method for manufacturing coloured solar cell modules. This method entails that the solar cells are installed behind a special transparent film, which hides the solar cells while having very little impact on their performance. The film has the advantage that it can be coloured in the desired colour. And this is the method which we’re now helping to refine through our research,” says Peter Poulsen.

When the project has been concluded, it should hopefully result in a new type of solar cell modules which can be adapted to the different requirements of most buildings and customers. To ensure aesthetic solutions, the project also involves architects.

“Imagine a company logo with built-in solar cells, so that the logo produces energy together with the rest of the roof without the solar cells being visible. This is what we would like to achieve. The aim is to be able to colour solar cells so that they are similar to tiles, slate, and patterns, and are adaptable to virtually all buildings,” says Peter Poulsen.

He adds that the project work also includes attempts to combine colourised solar cell modules with insulation, in which the solar cells are provided with insulation plates for prevention of energy loss.

New laboratory tests the solutions
The project solutions are tested in a new solar cell laboratory, which has just been built at DTU Risø Campus to give both researchers and industry access to develop, build, and test solar modules of all types and sizes.

“In Denmark, we cannot compete on making inexpensive solar cells. However, we can contribute to ensuring the technological solutions of tomorrow when it comes to building-integrated solutions. We have some strong companies and extensive know-how, which can put us at the forefront when we work together. And now we also have optimal conditions to test the solutions in our new state-of-the-art laboratory,” explains Peter Poulsen.

He expects that the new coloured solar cell modules in the project will be ready in 2020.