PV perovskites promise to be one of the most disruptive technologies in clean energy. With leading tandem module efficiencies pushing 27% and cells reaching 35%, the potential for high-performance solar is immense.

But the perovskite industry still resembles something of a technological Wild West. Production processes, equipment, characterization, and testing methods are evolving rapidly, with competing approaches and little yet settled.

Achieving long-term stability and durability – and proving both – remains the central challenge. And it was a major focus at this week’s Perovskite Connect here in Berlin.

Organizer Techblick reported that the event attracted more than 600 attendees and 90 exhibitors. It had a distinctly industrial focus this year, with materials and equipment suppliers showcasing a wide array of technologies to aspiring perovskite manufacturers and research laboratories.

“There is a durability playbook for silicon… that’s not true yet for perovskites,” said Adam Lorenz, CTO of CubicPV.

Lorenz presented the company’s latest findings on how temperature and seasonality affect power output. He explained how CubicPV’s in-house-developed, small-scale cell-testing chamber – the “PV Bake Oven” – had helped reveal perovskite defects that could then be addressed.

By modifying the perovskite “stack” based on Bake Oven testing, the company achieved notable efficiency gains. “Deploying that improved stack increased [perovskite] efficiencies from 16-17% to 18-19% with significantly better low-light performance in the field.”

Understanding how perovskites behave under real-world operating conditions – and using those insights to improve performance – will be critical to building confidence in the technology’s long-term durability.

CubicPV is pursuing a four-terminal (4T) architecture for its tandem modules, stacking perovskite-on-glass atop a conventional crystalline silicon (c-Si) module. The choice between 4T and two-terminal (2T) architectures is one of the key decisions facing perovskite developers, and the respective advantages of both approaches were a recurring theme at the event.

Long-running Chinese perovskite developer Microquanta revealed that it has achieved 26.5% efficiency with its full-scale 4T tandem module and is scheduled to ramp up a gigawatt-scale production facility in 2027. Microquanta’s Yang Chen argued that 4T avoids the current-matching constraints between the perovskite and crystalline silicon subcells, helping boost power output.

“We think the two-terminal is elegant and compact, but practically it is very easy to manufacture four-terminal at this stage – given perovskite is advancing every day,” said Chen.

The 4T versus 2T debate is about manufacturing alongside commercial readiness. The question is whether to build on existing silicon module technology with a relatively independent perovskite layer, or pursue a more integrated tandem device with potentially greater manufacturing complexity.

On manufacturing, vacuum-based processes are being combined with slot-die coating or inkjet printing for perovskite deposition and associated layers. One challenge for 2T production is depositing uniform, high-quality perovskite layers onto textured crystalline silicon surfaces that are optimized for light trapping. Combining different deposition processes appears to be allowing developers to overcome this hurdle.

Slot-die coating was reported to be commonplace in China, although inkjet technology also had a strong presence at the event in Berlin this week, with equipment suppliers from Korea, Germany, and the United States exhibiting.

Crystalline silicon PV has spent decades refining and standardizing its manufacturing processes. Perovskites are at a very different stage. Multiple architectures, deposition technologies and equipment platforms are all jostling for a place in future production lines.

With no dominant manufacturing approach yet established, equipment and materials suppliers are staking their claims across the emerging perovskite production landscape. For now, there is room for multiple technologies, although that is unlikely to remain the case indefinitely.

Perovskite PV is racing toward industrialization, but the winning technologies and manufacturing approaches are far from settled. For developers, the challenge is to turn remarkable efficiencies into durable, bankable products. For equipment and materials suppliers, the opportunity is to help establish the technologies that become industry standards.

The perovskite frontier remains wide open – but not everyone staking a claim will strike gold.

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