Tandem PV: Restoring American Leadership in Solar Innovation

As the clean energy transition accelerates, solar power is no longer a future bet—it’s the backbone of the new energy economy.

In 2024, nearly 90 percent of all new energy capacity came from clean sources—primarily solar, wind, and battery storage. But while solar is booming, one critical challenge remains: most core panel technologies and materials are still produced overseas, with China dominating the global photovoltaic supply chain.

One Silicon Valley startup is aiming to shift that dynamic.

Tandem PV, a California-based company, is developing a new kind of solar panel that’s not only more powerful but also designed to help restore U.S. leadership in solar manufacturing. At the core of its breakthrough is perovskite, a next-generation crystalline material that, when paired with traditional silicon, captures more sunlight and produces significantly more power than standard panels.

“This new technology is a chance to leap ahead because it’s fundamentally different from what conventional silicon offers,” says Tandem PV CEO Scott Wharton. “The U.S. once led the world in solar innovation. We gave that up. It’s time to reclaim that leadership.”

More Power , Less Land , Lower Costs

Tandem PV’s solution is known as a tandem solar panel, where a thin perovskite layer sits atop a stack of silicon cells. The dual-layer architecture captures a broader range of sunlight, increasing efficiency from the industry standard of around 21 percent to a potential 28–30 percent. That increased performance could reshape the economics of solar energy, especially at scale.

Unlike traditional silicon panels—which require massive energy inputs and complex manufacturing—perovskite layers are extremely thin, easier to produce, and highly efficient at capturing light.

This technological leap is more than an academic breakthrough. Tandem’s panels pack more energy into every square foot, which is a major advantage for utility-scale solar projects, the company’s primary market. Most of the cost of a solar installation (around 80 percent) isn’t the panels themselves but the land, labor, and infrastructure needed to install and maintain them.

By producing more power per panel, Tandem PV’s technology can shrink the size—and the price tag—of solar installations.

“Land and labor are expensive,” says Wharton. “With power demand skyrocketing, especially from AI data centers, efficiency isn’t just nice to have—it’s essential.”


The Clock Is Ticking

Electricity demand is rising fast, driven by electric vehicles, AI computing, and the electrification of everything from home heating to manufacturing. But the grid isn’t keeping pace.

Nuclear is too slow. Fusion is still years—or decades— away. Coal is no longer viable, as investors don’t believe it will deliver the expected 30-year payback. And natural gas? It’s facing multi-year backlogs—up to five years now— excluding permitting and installation times, just to build new infrastructure.
That leaves solar as one of the few options that is fast, scalable, and increasingly cost-effective.

“You can’t just flip a switch and get more gas online,” says Wharton. “We need power now, and solar is the best tool we have. Our job is to make it even better.”

Inside the Factory: A New Kind of U.S. Solar Manufacturing

Tandem PV is building the kind of solar factory the U.S. hasn’t seen in decades—one focused on advanced materials, high-throughput manufacturing, and modular scale-up. The company recently announced a $50 million funding round to support construction of its first commercial facility.

In addition, it was selected by the U.S. Department of Energy’s Solar Energy Technologies Office (SETO) for a $5.2 million award to help advance commercialization, and it received top honors at NREL’s 2023 Industry Growth Forum as the Best Venture in the Pre-Commercialization Track. Most recently, Tandem PV was also awarded a $4 million grant from the California Energy Commission to support rigorous performance and durability testing.

“We’re not just assembling modules,” says Wharton. “We’re building a vertically integrated supply chain around perovskite innovation—right here at home.”

The new facility will include equipment for applying ultrathin perovskite layers, testing lines for extreme-condition durability, and an automated assembly system optimized for utility-scale deployment.

The goal? To turn lab-grade performance into mass-market reality.

The Science Behind the Spark

So, what makes perovskite such a big deal?

First, it’s light and inexpensive to produce using a low-temperature, solution-based process, unlike the high-heat, energy-intensive steps required for silicon. Perovskites require only about 10 percent of the energy needed to manufacture an equivalent watt of silicon-based solar.

Second, its unique molecular structure allows it to absorb different parts of the solar spectrum than silicon, making it a perfect complement in a tandem configuration.

This layered approach dramatically increases efficiency with minimal added cost. And because the perovskite layer is only a few hundred nanometers thick—about 100 times thinner than a human hair—it can be applied quickly and precisely.

From Lab to Scale: The Durability Breakthrough

Tandem PV’s team includes some of the scientists who helped push perovskite research forward. Co-founder Colin Bailie, while a Ph.D. student at Stanford, helped build one of the world’s first working perovskite-silicon tandem cells. Chris Eberspacher, a solar energy innovator working to mainstream solar since the 1980s, was so impressed with Bailie's R&D that he joined as co-founder.

The company has now spent nearly a decade fine-tuning the chemistry for real-world resilience.

Durability has long been a concern for perovskites. Unlike silicon—which can last 25 to 30 years in the field—early perovskite cells degraded under heat, humidity, and UV exposure. But Tandem PV is solving that challenge through proprietary encapsulation techniques and material stabilization.

“Think about anything you leave in your backyard for 30 years,” Wharton says. “Now imagine it still works just as well. That's the level of reliability we are working towards achieving.”

Global Race, Local Advantage

Perovskite isn’t just the future of solar—it’s a global race. Dozens of startups and research institutions across Europe and Asia are vying to commercialize the technology. But only a few have moved beyond the lab into early production.

“We’re one of maybe eight companies in the world really pushing toward commercial-scale tandem perovskites,” says Wharton. “And one of a handful doing it with U.S.-based manufacturing.”

That distinction matters—not just for domestic supply chain resilience, but for national competitiveness in a market expected to grow to hundreds of gigawatts annually. By building both IP and production capacity in the U.S., Tandem PV is positioning itself as a strategic counterweight to China and other overseas producers.

Utility Buyers and the AI Power Surge

Unlike many cleantech startups focused on rooftop installations, Tandem PV targets utility-scale solar developers—the companies building massive solar farms to power industrial and commercial loads.

One of the fastest-growing drivers of that demand? AI data centers.

Generative AI workloads are significantly more energy-intensive than traditional computing. Some estimates suggest that a single AI query can consume up to 10 times the energy of a standard internet search. Multiplied across billions of queries, this surge is placing enormous strain on the electrical grid.

As large-scale data centers expand, they face increasing constraints: limited land availability, grid congestion, and long permitting timelines. High-efficiency panels like Tandem PV’s help address these issues by generating more power in less space—improving project viability and lowering system costs.

A Greener Way to Make Solar

Perovskites also offer significant environmental advantages. They don’t require high-purity quartz, intense heat, or rare-earth elements, making their carbon footprint far lower than that of conventional silicon production. That’s important as pressure grows to ensure solar panels are not just clean in use—but clean in origin.

“Cleaner energy needs cleaner manufacturing,” says Wharton. “With perovskite-silicon tandems, we’re moving toward a future where panels perform better and leave a smaller environmental footprint.”

Tandem PV’s panels are also designed to be easier to recycle, addressing another growing priority as the first wave of solar farms nears end-of-life.

What’s Next: A Platform for the Future

Tandem PV's next milestone is launching its first commercial production line and securing long-term agreements. From there, the company plans to scale production, deepen U.S. supply chain partnerships, and explore new product formats.

“This isn’t just about building a better solar panel,” says Wharton. “It’s about giving the U.S. a chance to lead in the next phase of clean energy—on American terms, with faster, smarter, more efficient technology that meets the moment.”