Swiss scientists’ transparent solar cells will be sweet for startups

As the European market for transparent solar panels grows, Swiss scientists have set a new efficiency record for the technology. This could pave the way for energy-generating windows that power our homes and appliances.

Also known as Grätzel cells, dye-sensitive solar cells (DSCs) are a type of low-cost solar cell that uses photosensitive dye to convert visible light into electricity.

Previous versions of DSCs relied on direct sunlight, but a team of researchers from the École Polytechnique Fédérale de Lausanne (EPFL) has found a way to create transparent photosensitizers. that can absorb light across the entire spectrum of visible light, both direct and ambient light.

Join AS in Valencia!

The heart of technology comes to the heart of the Mediterranean

The researchers developed a way to improve the combination of two newly designed photosensitizer dye molecules. They did this by creating a technique in which a monolayer of a hydroxamic acid derivative is pre-adsorbed onto the surface of nanocrystalline mesoporous titanium dioxide.

On top of the new photosensitizers that are able to harvesting light across the entire visible domain, the scientists have also improved the photovoltaic performance of the DSCs – which was a weak point of the technology compared to traditional solar cells.

To put that in numbers: the efficiency of the improved DSCs reached over 15% in direct sunlight and up to 30% in ambient light. For reference, commercial solar panels have an average efficiency between 15% to 22%.

In other words, if this technology can reach scale, we may soon see a transparent solar panel revolution in Europe.

How are DSCs already being used?

DSCs are not new technology, but the advances of the École Polytechnique Fédérale de Lausanne could provide a lifeline for sustainable buildings.

Dye-sensitive solar cells are not: only transparent, but also possible manufactured in multiple colors and at a low cost. Some are even used in skylights, greenhouses and glass facades.

For example, consider the SwissTech Congress Center — a site that became the first public building to install DSC technology in 2012.