In what many are calling a pivotal breakthrough for solar technology, researchers at the University of Sydney have achieved 27.06 % efficiency in a triple-junction perovskite-perovskite-silicon tandem solar cell — the highest ever reported for that architecture. Through clever chemistry and interface engineering, they also improved the material’s durability, pushing the technology closer to real-world deployment.
“It is an exciting time for solar research,” said Professor Anita Ho-Baillie, who led the work. “Perovskites are already showing us that we can push efficiencies beyond the limits of silicon alone. These advances mean we are moving closer to cheaper, more sustainable solar energy that will help power a low-carbon future.”
Why This Breakthrough Matters
- Beyond silicon’s constraints
Conventional solar panels rely on single-junction silicon cells, which adhere to the Shockley-Queisser limit — generally capping efficiency around 29–30 % under ideal conditions. Tandem cells stack materials with different bandgaps to harvest more of the solar spectrum, thereby surpassing those traditional limits. - Triple-junction design
In this case, the cell uses two perovskite layers plus silicon, each layer tuned to capture different wavelengths of light. By optimizing layers, reducing defects, and redesigning interfaces, the team pushed power conversion efficiency to new heights. - Improved stability
One of the traditional challenges with perovskite is degradation over time (moisture, heat, defects). The team addressed that by reengineering the perovskite composition and interfaces, making the cell less prone to defects or degradation — a crucial step toward commercial viability.
Challenges & Next Hurdles
- Scalability vs lab results
Laboratory prototypes can be highly tuned and small in area; scaling up to large, stable modules that survive years in the field is far harder. Many breakthroughs stall in the transition from lab bench to rooftop. - Longevity and durability
Even with improved stability, perovskites must match or exceed silicon’s proven multi-decade performance. Protecting them from moisture, UV, thermal cycling — and ensuring long-term reliability — remain major engineering challenges. - Manufacturing and costs
Creating multi-layer tandem cells requires precision, advanced deposition techniques, and defect control. For wide adoption, these processes must become cost-effective at scale. - Regulatory and certification pathways
New materials must undergo rigorous testing and certification before they can be trusted for commercial or utility-scale deployment. That’s often a slower, more conservative path than university labs might hope.
The Outlook Ahead
This record doesn’t just push a number — it signals that perovskite-enhanced solar technology is rapidly maturing. The direction is clear: higher efficiencies, smarter materials, better interfaces, and more durable design.
If the field can overcome scale and durability challenges, tandem cells like this may usher in a new generation of solar modules — offering lower costs per watt, smaller panel areas for a given output, and better return on investment for solar deployment.