Transparent solar cells: Will windows generate electricity?
The solar cell consists of inexpensive materials like zinc oxide and nickel oxide for the n and p layer, respectively. Its architecture facilitates large-area applications; for instance, it could be deposited on glass areas. “Hitherto, no transparent diode material was available that at the same time was suited for solar cells”, said professor Marius Grundmann who oversees the research team.
The transparent solar cell absorbs exclusively light in the ultraviolet part of the light spectrum to generate electricity. This can be regarded as a drawback since only a small portion of the spectrum is utilised. This factor translates into a very low energetic efficiency. However, based on the used part of the spectrum, the efficiency is not so bad – about 3 percent, explained Grundmann. “This is actually rather high, compared to the efficiency of available UV-sensitive cells”, he said.
For the time being, the researchers are utilising the solar cell to power an electric circuit that fittingly is also made of transparent materials. In the medium term, the team plans to optimise the efficiency and try out a variety of alternative cost-effective semiconducting materials.
The technology scales well, Grundmann said. Some optimisation provided, it would possible to produce coated objects (glass plates) the size of a sheet of writing paper. “Such a size is within reach”, he added. Under industrial production conditions, which however are several years away, even larger carrier plates would be possible.
Further information: https://research.uni-leipzig.de/hlp/