Butterfly Solar Cell Technology in Germany

Butterfly solar technology – Researchers at the Karlsruhe Institute of Technology in Germany have managed to double the amount of energy solar panels convert to energy by studying the nanostructures of black butterfly wings.

How does it work?

Radwan Siddique at the Karlsruhe Institute of Technology was reading about butterfly wings whilst researching a technique for building 3d nanostructures. “I was so intrigued that I literally went to a lot of butterfly nurseries and gathered several butterflies,” Siddique told Seeker. “The black butterfly was one of them. I was putting them under SEM (a scanning electron microscope) and looking at the structures.” 

Although the openings on the black butterfly’s wings are less than a millionth of a metre wide, the latticed nanostructures they’re made of scatter light and are able to help the butterfly absorb more of the sun’s heat, helping the butterfly (a cold-blooded insect) regulate its body temperature and fly in cool weather. 

Butterfly Solar
Butterfly Solar – Scanning electron microscope image of bio-inspired nanoholes (source: seeker.com via Radwanul Siddique, KIT)

Butterfly Solar Cells – Production

According to Science Advances on October 18, when the findings were published, the “nanopatterned absorbers achieve a relative integrated absorption increase of 90% at a normal incident angle of light to as high as 200% at large incident angles, demonstrating the potential of black butterfly structures for light-harvesting purposes in thin-film solar cells.”

Siddique and his colleagues used a sheet of hydrogenated amorphous silicon in an attempt to copy the structure of the black butterfly wings. When they used a layer of polymer with circular indentations of different sizes, and transferred it to a silicon base, they were able to produce the solar power at a high efficiency using a thin film, as opposed to standard crystal based cells. Some potential uses for these thin-film solar cells could be the incorporation into solar windows or other structures that wouldn’t work well with the crystal-based solar cells. 

The cells are also quick and easy to create – “the way we produce the structure is so simple,” Siddique says, “We need just 5 minutes to 10 minutes to make the nanostructures on a six-inch wafer of silicon.” The butterfly creates these nanostructures by combining proteins to cause a chemical interaction. Siddique’s team created artificial versions of these proteins to manufacture their butterfly solar cells – which are cheap and scalable.

Still early days yet, but it’ll be exciting to see how ‘butterfly solar’ stacks up against other emerging solar tech such as perovskite solar cells

 

 

SONOB Installation on Dutch Highways (IIPV)

The Netherlands is expanding a test of solar panel sound barriers (SONOB) as part of a project replacing currently installed sound barriers. The usage of Infrastructure Integrated Photovoltaics (IIPV) (Also known as Building Integrated Photovoltaics (BIPV)) is being used in the Tesla Solar Roof, solar windows, and many more locations worldwide. 

SONOB Trial in Holland – Phase 2

SONOB Solar Highway Netherlands Heijmans Van Campen Bayards
SONOB Solar Highway in the Netherlands (source: vancampenbayards.com)

Electrek are reporting that, following a successful 2014 trial in Hertogenbosch of the technology, a new project will commence construction early next year. They plan to connect to the grid later in 2018. The 68 discrete sound barriers will be five metres high and four metres wide along a 400 metre stretch of highway. This will make Solar Highways the largest project in Europe using integrated solar cells in noise barriers to generate power whilst also stopping noise pollution in the surrounding neighbourhood. 

The project will be undertaken by Heijmans in conjunction with Rijkswaterstaat (Ministry of Infrastructure and the Environment), Energy research Centre of the Netherlands (ECN) and the Solar Energy Application Centre (SEAC) – and the location of it is next to the A50 at Uden. Heijmans will be collaborating on the construction with Scheuten, Van Campen Bayards and Libra Energy.

SONOB Technology

The 2014 project explored the efficiacy of two disparate methods – semi-transparent crystalline silicon-based solar noise barriers, and semi-transparent coloured plates which used solar concentrator technology. According to SEAC, after key learnings in the 2014 trials were utilised, a SONOB ‘living lab’ was installed in Den Bosch which adds extra functionality to improve soundproofing, scalability, noise barrier requirements, semi-transparency, and so on. 

The new barriers, facing north/south and east/west, are equipped with two Luminescent Solar Concentrators (LSC) with c-Si and GaAs cells and two panels with mono and bi-facial c-Si cells. The goal is to create a ‘breakthrough modular solar noise barrier concept’ that could be rolled out countrywide (and farther!). 

We’ll wait for results on this and also be sure to report on any new IIPV/BIPV installations coming up in the future to monitor how this exciting technology is progressing!