The Dubai Electricity and Water Authority’s (DEWA) Research and Development Center is spearheading groundbreaking research into innovative vacuum deposition technology tailored for the fabrication of high-efficiency perovskite-crystalline silicon tandem solar cells.
This groundbreaking work aims to propel solar technology into a new era of efficiency. Key focuses include optimizing thin film deposition processes, enhancing interface engineering, and minimizing defects.
Dr. Luis Martin Pomares, Vineeth Krishnan, Dr. Sgouris Sgouridis and Joseph Abi Nader from the DEWA R&D Center said that the commercialization of perovskite-crystalline silicon tandem solar cells depends not only on technical performance, but also on scalability, cost-effectiveness, and long-term reliability. To address these challenges, they developed a two-phase plan:
The first phase focuses on wet chemical deposition methods for small batteries, laying the foundation for initial development.
The second phase uses specialized vacuum cluster tools to scale up to large-area wafer deposition for industrial applications.
Throughout the process, DEWA R&D prioritizes optimal cell and module designs to exceed the efficiency, reliability, and longevity of traditional photovoltaic modules. This holistic approach underlines Dubai Electricity and Water Authority’s commitment to advancing sustainable energy solutions for the future.
Recently, the solar team at the DEWA R&D Center announced a breakthrough, achieving over 30% efficiency using a four-terminal configuration of perovskite/silicon tandem solar cells.
This achievement was achieved by modifying the carrier transport layer of the top perovskite solar cell, resulting in a significant increase in current density and overall efficiency to 21.41%.
The team fabricated perovskite solar cells by modifying the electron transport layer and mechanically stacked the same perovskite solar cell device (without metal electrodes) as a filter on a silicon solar cell for a 4-T tandem configuration, which the efficiency is 8.86%.
Combining these two efficiencies, the team's internally measured 4-T perovskite/silicon tandem solar cell achieved an efficiency of 30.27%. Recent achievements have shown that perovskite/silicon tandem solar cells have great potential to increase energy production compared to conventional silicon technologies.
However, 4-T series cells cannot be readily used in commercial PV deployments as they essentially require double the amount of wiring and inverter connections. The team is therefore working on developing two- and three-terminal perovskite solar cells that can be used in the same way as existing conventional modules. This requires careful bandgap tuning and novel module wiring methods.
The stability of perovskite materials in the presence of moisture and light is an important issue. Furthermore, scalability and manufacturing consistency remain key barriers to the commercialization of tandem solar cells. Researchers are actively exploring packaging strategies, interface engineering, and material compositions to improve stability and extend device lifetime in hot desert climate conditions.
Likewise, to scale up perovskite/silicon tandem solar cells, the solar team is procuring a cluster of tools consisting of automated high-quality thin film deposition technologies, such as two low-temperature and one high-temperature thermal evaporators, atomic layer deposition, radio frequency type magnetron sputtering, load lock and main process chamber and glove box.
In addition, the team purchased coating and printing technologies such as spin coaters, blade coaters, slot die coaters and screen-printing machines to scale up tandem solar cells. The researchers are currently collaborating with academic and industrial research centers such as CSEM Switzerland, ISC Konstanz, UAE University and the Chinese Academy of Sciences.