Researchers at the University of New South Wales (UNSW) Sydney have made significant strides in solar technology that may revolutionize the way sunlight is harnessed for energy. A team from UNSW, known as Omega Silicon, has successfully demonstrated a process called singlet fission, which allows a single photon of light to be converted into two packets of energy. This advancement could effectively double the electrical output of solar panels, addressing a critical limitation in renewable energy efficiency.
The discovery comes as part of ongoing efforts to make solar energy cheaper and more efficient. Currently, most commercial solar panels, which are predominantly made from silicon, convert about 27% of sunlight into electricity, with a theoretical maximum efficiency of 29.4%. By utilizing singlet fission, the UNSW team aims to surpass this barrier and enhance solar panel performance significantly.
Understanding Singlet Fission
Singlet fission is a process where high-energy photons striking specific organic materials can produce two lower-energy excitations. This transformation effectively yields two usable energy packets instead of one. According to Dr. Ben Carwithen, a postdoctoral researcher at UNSW’s School of Chemistry, a considerable amount of energy from light in solar cells is often lost as heat. “We’re finding ways to take that wasted energy and turn it into more electricity instead,” he stated.
The UNSW team has identified a stable organic compound named DPND (dipyrrolonaphthyridinedione) that can facilitate this process while remaining effective in real-world outdoor conditions. Previous research had focused on compounds like tetracene, which, while promising in laboratory settings, degraded too quickly when exposed to air and moisture.
Innovations in Solar Cell Design
The integration of singlet fission into silicon solar panels could lead to substantial efficiency gains. Professor Ned Ekins-Daukes, project lead and head of UNSW’s School of Photovoltaic & Renewable Energy Engineering, emphasized that this innovation allows for a molecular layer to contribute additional current to the panel. “Introducing singlet fission into a silicon solar panel will increase its efficiency,” he noted.
This approach builds on over a decade of foundational research led by Professor Tim Schmidt, who pioneered the use of magnetic fields to investigate the singlet fission pathway. “We used magnetic fields to manipulate the emitted light and reveal how singlet fission occurs,” Professor Schmidt explained. By comprehending the underlying physics, the researchers have been able to design more effective materials and structures to optimize the process.
The potential of singlet fission is vast, with theoretical efficiencies for solar panels reaching up to 45%. “Pushing towards 30% would already be fantastic,” Dr. Carwithen remarked, while expressing hope for even higher efficiency levels.
Industry Impact and Future Prospects
This research is part of a broader initiative supported by the Australian Renewable Energy Agency (ARENA), which selected UNSW’s singlet fission project in 2023 for its Ultra Low Cost Solar program. This initiative aims to deliver solar panels with over 30% efficiency at less than 30 cents per watt by 2030.
With interest from seven of the world’s largest solar companies, the Omega Silicon team is poised to make a significant impact on the industry. “We have industry partners waiting in the wings,” Dr. Carwithen stated, indicating the readiness to commercialize this technology pending successful lab results. While a small-scale proof of concept could be achieved within a few years, Dr. Carwithen acknowledged the unpredictable nature of scientific progress, suggesting a more realistic timeline of five years for practical applications.
This groundbreaking work represents a collaborative effort among various disciplines at UNSW, including physics and chemistry, reflecting a multidisciplinary approach to solving complex challenges in renewable energy. The innovations emerging from UNSW could play a pivotal role in the future of solar technology, making sustainable energy more accessible and efficient worldwide.
