Tandem - Page 11

Researchers at the Indian Institute of Technology Bombay have reported NIR-transparent perovskite solar cells (PSCs) with the stable triple cation perovskite as the photo-absorber and subsequent integration with a Si solar cell in a 4T tandem device. The scientists said that the cell provides outstanding stability in the dark, as well as continuous heating conditions.

The top perovskite cell incorporates a room-temperature sputtered transparent conducting electrode (TCE) as a rear electrode. It has an n–i–p structure and utilizes an anti-reflecting coating, an electron transport layer (ETL) made of tin(IV) oxide (SnO₂), a perovskite layer, a molybdenum oxide (MoOx) layer, and a spiro-OMeTAD hole transport layer (HTL). The MoOx buffer layer protects the perovskite photo-absorber and charge transport layers from any sputter damage.

Researchers at the Ningbo Institute of Materials Technology and Engineering (NIMTE) of the Chinese Academy of Sciences (CAS), University of Macau and Celanese (China) Holding have developed a long-alkyl- chain anionic surfactant (LAS) additive that can significantly improve the long-term operational stability of perovskite/silicon tandem solar cells.

Traditional methods to improve the stability of perovskite solar cells include encapsulation, crystallization engineering, and defect passivation. Similar to “stress corrosion” in metals, glass and polymers, subcritical perovskite deterioration inevitably occurs due to tensile stress during the fabrication and operation, which degrades device performance. To suppress the “stress corrosion”, the researchers developed the novel LAS additive for the perovskite/silicon tandem solar cells.

Scientists from Karlsruhe Institute of Technology (KIT) have developed a new way to fabricate micro-patterned translucent perovskite solar cells that could be used in tandem solar modules intended for applications in building-integrated photovoltaics (BIPV). “While translucent perovskite multi-junction devices have been envisaged and recognized as a promising path towards high- efficiency neutral-color transparent PV, the tolerance of complex perovskite tandem stacks against extensive laser scribing has yet to be explored,” the research group said.

The researchers noted that the cells have thus far provided decent levels of power conversion efficiency while maintaining a high average visible transmittance (AVT). They used a custom-built laser scribing setup to fabricate a perovskite solar cell with n–i–p architecture and with an active area of 0.105 cm². The device is based on an indium tin oxide (ITO) substrate, a hole transport layer made of carbazole (2PACz), an electron transport layer made of buckminsterfullerene (C60), an absorber based on methylammonium lead triiodide (CH3NH3PbI3), a bathocuproine (BCP) buffer layer, and a gold (Au) metal contact.

The US Department of Energy (DoE) has announced USD$52 million (EUR 47.5 million) in funding for 19 research, development and demonstration projects that seek to strengthen domestic solar manufacturing, support the recycling of solar panels and develop new solar technologies.

This funding will back several projects, among which two projects, led by the Massachusetts Institute of Technology (MIT) and the University of Colorado Boulder, will receive a total of USD$18 million through the PV Research and Development funding programme to advance perovskite solar cell devices.

The U.S. Department of Energy Solar Energy Technologies Office (SETO) has announced that a team of researchers, led by MIT and including the University of California San Diego, has been selected to receive a $11.25 Million cost-shared award to establish a new research center that will advance the development of next-generation solar cells for commercial use.

A collaborative effort with CubicPV, solar startup Verde Technologies, and Princeton University, the center will bring together teams of researchers to support the creation of perovskite-silicon tandem solar modules. These are solar cells made of stacked materials—silicon paired with perovskites—that together absorb more of the solar spectrum than single materials, resulting in a dramatic increase in efficiency. Their potential to generate significantly more power than conventional solar cells could make a meaningful difference in the race to combat climate change and the transition to a clean-energy future.

Researchers from the Photovoltaics Laboratory (KPV-Lab) at King Abdullah University of Science and Technology (KAUST) have reported a perovskite/silicon tandem solar cell with a power conversion efficiency (PCE) of 33.2%—the highest tandem device efficiency in the world to date, surpassing that of Helmholtz Zentrum Berlin's (HZB) record at 32.5% PCE.

The tandem device was reportedly certified by the European Solar Test Installation (ESTI) and listed at the top of the National Renewable Energy Laboratory's (NREL), Best Research-cell Efficiency Chart.

This is a sponsored post by MBRAUN

For years, the Helmholtz-Zentrum in Berlin has been researching the development of highly efficient perovskite tandem solar cells with great success. The HySprint Innovation Lab was founded specifically for this purpose, which cooperates internationally with other research groups as well as with industrial partners.

Many process steps are necessary to produce these highly efficient perovskite cells, which can all be realized together in the HySprint laboratory. A good research environment and high-quality equipment allow researchers to work optimally on their projects. The results at HZB are impressive. In recent years, the researchers have made significant progress in the field of perovskite tandem solar cells and achieved independently certified world record of tandem solar cells.

TNO, in cooperation with Dutch and German industrial partners, is advancing a perovskite/silicon tandem solar module suitable for early market introduction. 

FIT4Market, a four-year research project supported by the Netherlands Enterprise Agency (RVO), will help drive CO₂ reduction through to 2030, supporting national climate objectives. It is also a step towards bringing PV production back to Europe and rebuilding a competitive PV supply chain.

University of California, Los Angeles (UCLA) researchers have joined forces with Swedish building-integrated PV (BIPV) module manufacturer, Midsummer, on a project that has yielded a four-terminal (4T) tandem solar cell based on a top cell made of perovskite and a bottom cell relying on copper, indium, gallium and selenium (CIGS).

The joint project between Midsummer and Prof. Yang's lab at UCLA resulted in a four-terminal perovskite-CIGS tandem solar cell, based on a commercial CIGS solar cell,  that reached 24.9 percent efficiency. The solar cell was based on a perovskite top cell that has been optimized for integration with Midsummer’s CIGS cells that are utilized in their commercial suite of BIPV products.

Researchers at France's National Solar Energy Institute (INES) – a division of the French Alternative Energies and Atomic Energy Commission (CEA) – and Italian renewables specialist Enel Green Power have reportedly developed a two-terminal tandem perovskite-silicon solar cell with a power conversion efficiency of 26.5%. 

The scientists said the new result improves on the 25.8% efficiency they achieved for the same kind of cell in December 2022. “The device with an active area of 9 cm² has an open-circuit voltage above 1,880 mV,” CEA-INES said, noting that the improvement on the device, which is based on a p-i-n configuration, was also due to “shading correction.” No additional technical details were disclosed.