Tandem PV Launches 40-MW Perovskite-Silicon Plant in California

• Tandem PV launches a Fremont perovskite-silicon tandem panel factory, scaling 40MW annually to validate high-efficiency cells and set up commercial sales in 2026.

Tandem PV on Monday opened a commercial demonstration solar-panel factory in Fremont, California, with about 40 MW of annual nameplate capacity. The 65,000-square-foot facility is designed to validate manufacturing of perovskite-silicon tandem panels at roughly 60 times the size of the company’s R&D devices, moving the technology toward repeatable commercial production.

Tandem PV’s approach combines a thin perovskite layer with conventional silicon cells to capture more of the solar spectrum. The company reported 29.7% efficiency in internal testing and less than 1% average annual power loss in accelerated lifetime trials. It plans customer validation later this year, expects first commercial sales in 2026, and targets high-volume manufacturing in 2028. The company has raised $87 million from investors including Eclipse and Constellation Energy and from U.S. government agencies.

What does Tandem PV’s Fremont 40 MW tandem factory mean for commercial perovskite-silicon solar?

• Scales perovskite-silicon tandem from lab to factory: A dedicated commercial-scale line is a major step toward proving that tandem performance can be reproduced consistently outside of R&D conditions.De-risks “repeatability” issues that have historically limited perovskite deployment: Commercial manufacturing demands stable material quality, uniform layer deposition, and tight process control—areas where pilot lines and demos provide the first real stress tests.
• Accelerates yield and reliability learning: Running wafers and full panel stacks at scale helps identify bottlenecks in throughput, defect rates, and failure modes, which are critical for lowering cost and improving bankability.
• Provides an integration pathway with silicon supply chains: By pairing a perovskite top cell with existing silicon manufacturing ecosystems, Tandem PV’s factory can reduce how far the industry must move away from proven silicon production infrastructure.
• Enables iteration on module-level architecture: Moving from small devices to full-area panels allows testing of encapsulation, interconnects, and module assembly choices that strongly affect real-world durability.
• Supports accelerated qualification for customer trials: Demonstration manufacturing at tens of megawatts/year helps generate sufficient inventory for validation programs, including environmental stress testing and performance characterization needed by commercial buyers.
• Helps benchmark manufacturing cost drivers: Throughput, materials utilization (including any expensive layers), scrap rates, and equipment utilization become measurable—turning “promising technology” into trackable unit-economics.
• Signals investor and policy confidence in perovskite manufacturing: Government and private funding backing a factory-oriented milestone suggests perovskite tandem is moving from concept funding toward industrialization.
• Creates a reference model for future perovskite fabs: If the Fremont line successfully establishes scalable processes, it can inform how subsequent lines are designed for higher volume manufacturing and faster deployment.
• Improves confidence in the technology’s scaling timeline: Targeted schedules for validation, first sales, and high-volume production indicate a pathway to commercialization rather than indefinite prototyping.
• May influence industry momentum and partnerships: A visible factory can attract offtakers, equipment suppliers, and component partners interested in stable, near-term supply of tandem modules.
• Expands the learning curve for perovskite stability at scale: Manufacturing scale can expose issues—such as variability in perovskite morphology or sensitivity during processing—that smaller R&D builds may not reveal.