In a significant step towards the commercialisation of next-generation solar cells, researchers at the University of Sydney have achieved a key milestone. Professor Anita Ho-Baillie and her team, supported by the Australian Centre for Advanced Photovoltaics (ACAP) and the Australian Renewable Energy Agency (ARENA), have developed a perovskite-silicon tandem solar cell that meets international durability and efficiency standards. This advancement places the team among an elite group of only eight global research entities to have demonstrated a certified 30% efficient monolithic perovskite-silicon tandem cell, the first Australian group to do so.
The tandem cell, which combines a perovskite layer with silicon, holds the promise of higher energy conversion efficiency compared to traditional silicon cells. While silicon, the standard material in solar panels, has a theoretical efficiency limit of 30%, tandem cells, by combining two materials with complementary light absorption capabilities, have a potential efficiency of up to 45%.
A crucial hurdle in perovskite development has been their notorious instability. Reacting poorly to environmental factors like oxygen, moisture, and heat, perovskites have struggled to match silicon’s longevity. However, Ho-Baillie’s team has made significant progress. In 2020, they gained global recognition for improving the thermal stability of perovskite cells using a low-cost polymer-glass encapsulation technique. This advancement enabled perovskite cells to pass several key industry standard tests.
Building on this, the team’s tandem solar cells have now demonstrated stability after 400 thermal cycles—double the threshold set by the International Electrotechnical Commission (IEC) standards. This breakthrough has been published in Advanced Energy Materials, with further research on light and heat stress expected soon.
To ensure the commercial viability of their breakthrough, Ho-Baillie’s team is collaborating with Australian solar technology company SunDrive. SunDrive has developed low-cost metallisation technology, using copper instead of silver, to further reduce the manufacturing costs of solar cells. Together, they aim to create cost-effective, industry-scalable solutions to bring perovskite-silicon tandem cells to market.
The ultimate goal is to drive down the cost of solar energy to 30 cents per watt installed by 2030, with an efficiency target of 30% or more, making solar power an even more competitive renewable energy source.
With continued backing from ACAP, ARENA, and industry partners like SunDrive, Professor Ho-Baillie’s team is pushing forward in the global race to commercialise high-efficiency, durable solar cells. This marks another step towards making solar energy more affordable and accessible, further solidifying Australia’s role in driving renewable energy innovation.