Benchmarking ES Foundry in a dynamic and diversified U.S. cell production landscape

This is a story about where American solar panels come from, not something that changes your options right now, but it's worth knowing about if you're weighing solar for your home.

Since 2022 federal incentives pushed most U.S. solar investment into assembling finished panels, while the solar cells inside those panels (the part that actually converts sunlight into electricity) mostly still came from overseas, especially Indonesia. One company, ES Foundry, set out to change that by focusing only on making cells, rather than both cells and panels together like some competitors. It retrofitted an old Fujifilm camera and photo-paper factory in Greenwood, South Carolina, starting production in early 2025 with a 1 gigawatt cell line. By the end of 2025 that line was running at full capacity, and the company now plans to triple output to 3 gigawatts by the end of 2026.

ES Foundry chose an older, well-proven solar cell technology called PERC rather than newer options, because it's easier to get consistent quality while training a new workforce and rebuilding U.S. manufacturing know-how. The company says materials like paste and chemicals used in cell production are still mostly imported from China, though it sees more domestic suppliers starting to invest here too.

For homeowners, none of this changes rebates or prices today, but it points toward more solar panels down the road being made with U.S.-manufactured cells rather than imported ones.