A new world efficiency record has been set for thin film silicon solar cells by EPFL’s Institute of Micro-engineering, reaching an impressive 10.7%. That is a significant increase in efficiency from the previous record of 10.1%. The new single-junction microcrystalline silicon solar cell had it’s record independently verified by the Fraunhofer Institute for Solar Energy Systems.
“Deep understanding has been gained these last years in material quality, efficient light-trapping and cell design, which in combination with careful process optimization led to this remarkable world-record efficiency,” says Simon Hänni, a PhD student at IMT Neuchâtel.
Impressively, the solar cell consists of just 2 micrometers of photovoltaic active material, which is a significant advantage, allowing it to be easily incorporated into larger modules. Standard wafer-based crystalline silicon photovoltaic technology currently uses absorber layers — “with a thickness of about 180 micrometers for module conversion efficiency of 15 to 20%, 10.7% efficiency was reached here with only 1.8 micrometers of silicon material, i.e. 100 times less material than for conventional technologies, and with cell fabrication temperature never exceeding 200°C,” Ecole Polytechnique Fédérale de Lausanne writes.
Using considerably less material will go a long way towards reducing the cost and weight of modules.
“The reported progress is of paramount importance for increasing further TF-Si PV devices efficiency and potential, as at least one microcrystalline silicon junction is systematically used in combination with an amorphous silicon junction to form multiple junction devices for a broader use of the solar spectrum,” Ecole Polytechnique Fédérale de Lausanne adds. “The reported record efficiency clearly indicates that the potential of TF-Si multi-junction devices can be extended to > 13.5% conversion efficiency with a minimum usage of abundant and non-toxic raw material at low costs.”
This announcement follows right behind other very exciting developments in the thin film solar industry, including the announcement that new thin film solar power is being sold for less than coal power in New Mexico.
Image Credit: © PVLab / EPFL