Thin-Film Solar Cell Approaches Efficiency Record
A Copper Zinc Tin Selenide (CZTSe) solar cell technology has achieved an efficiency of 9.7% and an open-circuit voltage of 0.41 volts, a bit less than the 0.5 volts that most silicon-based solar cells achieve. (Solar cells are generally connected in series, which multiplies their voltage by the number of cells in the series connection.)
The new solar cell technology is based on thin-film CZTS solar cells which were developed due to the abundance as well as the low cost (relatively speaking) of copper, zinc, tin, and sulfur.
In this case, the “S” stands for selenide, rather than sulfur. Selenide is a compound containing selenium.
“This is a big win for us. We’ve been working toward this milestone since 2011 when we first started our research on alternative materials for thin-film photovoltaics at imec/imomec,” said Marc Meuris, program manager Solliance of the alternative thin-film PV program. “Our efficiencies are the highest in Europe and approaching the world record for this type of thin-film solar cells, and we look forward to further advancing R&D to help bringing to market sustainable energy sources.”
CZTS cells provide the promise of generating solar power with the use of only abundant materials, they have even achieved up to 11.1% efficiency (by IBM), and they may even be printable. (IBM actually hit 9.6% efficiency in 2010.)
“The sputtering of the Cu, Zn, Sn layers was performed at Flamac (Gent), and the international glass manufacturer AGC delivered Molybdenum-on- glass substrates,” imec writes. “Imec’s thin-film solar cell activities at imomec (imec’s associated laboratory at the university of Hasselt) are integrated in the Solliance cross-border collaboration platform, and the research was partially supported by the Flemish ‘Strategisch Initiatief Materialen’ (SIM) SoPPoM program.”
Selenium is not as abundant as sulfur. However, research and development like this are still a step in the right direction.
This CTZSe cell technology will be presented at the Intersolar conference in San Francisco, imomec, in imec’s associated lab at the Hasselt University, and Solliance.