Offshore floating solar projects can help overcome limitations of land while tapping into maximum sunlight in sun rich regions.
In an article published in the Journal of Materials Chemistry C, Brazilian researchers describe a strategy to enhance the efficiency and stability of solar cells made of perovskite, a semiconductor material produced in the laboratory. The results of the project could be highly positive for the future of the solar power sector.
Developed by researchers at São Paulo State University (UNESP) in Bauru, Brazil, the method involves the use of a class of materials known as MXenes, a family of two-dimensional materials with a graphene-like structure combining transition metals, carbon and/or nitrogen, and surface functional groups such as fluoride, oxygen or hydroxyl. Their properties include high electrical conductivity, good thermal stability, and high transmittance (relating to the amount of light that passes through a substance without being reflected or absorbed).
In the study, the MXene Ti3C2Tx was added to polymethyl methacrylate (PMMA) to form a passivation coating, which was spin-coated on top of the perovskite layer of inverted solar cells. Passivation coatings are designed to mitigate possible defects in polycrystalline solids (perovskite in this case) due to interaction with the environment or to their internal structure.
Artificial intelligence (AI) has the potential to transform technologies as diverse as solar panels, in-body medical sensors and self-driving vehicles. But these applications are already pushing today’s computers to their limits when it comes to speed, memory size and energy use.
Fortunately, scientists in the fields of AI, computing and nanoscience are working to overcome these challenges, and they are using their brains as their models.
That is because the circuits, or neurons, in the human brain have a key advantage over today’s computer circuits: they can store information and process it in the same place. This makes them exceptionally fast and energy efficient. That is why scientists are now exploring how to use materials measured in billionths of a meter— nanomaterials—to construct circuits that work like our neurons. To do so successfully, however, scientists must understand precisely what is happening within these nanomaterial circuits at the atomic level.
Researchers at King Abdullah University of Science and Technology (KAUST) have developed a comprehensive plan to introduce perovskite/silicon tandem solar cells into the marketplace, setting the stage for a world energized by widespread, cost-effective renewable energy, both in Saudi Arabia and globally.
The authors of the article, published in esteemed journal Science, include Prof. Stefaan De Wolf and his research team at the KAUST Solar Center. The team is working on improving solar efficiency to meet Saudi Arabia’ solar targets.
Perovskite/silicon tandem technology combines the strengths of two materials – perovskite’s efficient light absorption and silicon’s long-term stability – to achieve record-breaking efficiency. In 2023, the De Wolf laboratory reported two world records for power conversion efficiency, with five achieved globally in the same year, showing rapid progress in perovskite/silicon tandem technology.
Until recently, chalcopyrite-based solar cells have achieved a maximum energy conversion efficiency of 23.35%, as reported in 2019 by Solar Frontier, a former Solar Energy company based in Japan. Further boosting this efficiency, however, has so far proved challenging.
Researchers at Uppsala University and at the First Solar European Technology Center AB (former Evolar AB) in Sweden recently attained a higher efficiency of 23.64% in chalcopyrite-based solar cells. This efficiency, reported in Nature Energy, was achieved using two primary techniques, namely high-concentration silver alloying and steep back-contact gallium grading.
“A primary objective of our study was to increase the efficiency of CIGS-based thin-film solar cells to ultimately lower the price per Watt-peak of corresponding large-scale modules,” Jan Keller, first author of the paper, told Phys.org. “Our work makes use of the findings from many research groups around the world, obtained during the last decades.”
The key revelation from this study is the dual impact of the passivation process.
MIT’s research is set to make solar panels lighter, cheaper, and more efficient by addressing key challenges associated with perovskite solar panels.
There is no doubt that water is significant. Without it, life would never have begun, let alone continue today—not to mention its role in the environment itself, with oceans covering over 70% of Earth.
But despite its ubiquity, liquid water features some electronic intricacies that have long puzzled scientists in chemistry, physics, and technology. For example, the electron affinity, i.e., the energy stabilization undergone by a free electron when captured by water, has remained poorly characterized from an experimental point of view.
Even today’s most accurate electronic structure theory has been unable to clarify the picture, which means that important physical quantities like the energy at which electrons from external sources can be injected in liquid water remain elusive. These properties are crucial for understanding the behavior of electrons in water and could play a role in biological systems, environmental cycles, and technological applications like solar energy conversion.
Perovskites, a broad class of compounds with a particular kind of crystal structure, have long been seen as a promising alternative or supplement to today’s silicon or cadmium telluride solar panels. They could be far more lightweight and inexpensive, and could be coated onto virtually any substrate, including paper or flexible plastic that could be rolled up for easy transport.
In their efficiency at converting sunlight to electricity, perovskites are becoming comparable to silicon, whose manufacture still requires long, complex, and energy-intensive processes. One big remaining drawback is longevity: They tend to break down in a matter of months to years, while silicon solar panels can last more than two decades. And their efficiency over large module areas still lags behind silicon.
Now, a team of researchers at MIT and several other institutions has revealed ways to optimize efficiency and better control degradation, by engineering the nanoscale structure of perovskite devices.
CIGS solar cells can also be used a bottom layer in the tandem solar cell design helping reduce production costs.
Researchers at Uppsala University in Sweden have created a new world record by designing a CIGS solar cell with 23.64 percent energy conversion efficiency.
