Tin oxide replaces scarce indium in solar mini-modules, bringing cheaper clean energy closer to market

Summary

Researchers at Monash University have developed a commercial-scale tandem solar cell that achieves 31% efficiency on a 207.9 cm² mini-module using abundant and inexpensive tin oxide instead of rare and costly indium.

Why it matters

This breakthrough reduces dependence on scarce resources like indium, lowering costs while delivering high efficiency and durability, thereby enhancing the scalability of next-generation photovoltaic technologies. It represents a strategic step toward making solar energy accessible to broader populations and moving closer to terawatt-scale production goals.

Highlights

• %33 efficiency achieved in 1 cm² cells and %31 efficiency achieved in 207.9 cm² mini-modules.
• Tin oxide, a material costing only about 1% of indium, is employed using a reactive plasma deposition process.
• The devices demonstrated resilience to heat, humidity, and outdoor conditions, maintaining high performance for over three months.

Critical take

While the efficiency gains are impressive, the long-term environmental durability of tin oxide layers and the cost-effectiveness of large-scale manufacturing processes remain insufficiently validated.