ES Foundry Triples South Carolina Solar Cell Capacity to 3 GW

ES Foundry has finished a 2 GW expansion at its Greenwood, South Carolina factory, raising annual production capacity to 3 GW, according to pv magazine.

The factory started up in January 2025 and hit its full 1 GW operational rate by year end. It turns out crystalline silicon bifacial cells built on passivated emitter and rear contact (PERC) technology.

Domestic cell output remains thin against module assembly. Wood Mackenzie analysts put U.S. operational solar cell manufacturing capacity at just 3 GW earlier this year, with a forecast of 20.5 GW by the end of 2027. Module assembly capacity already tops 45 GW according to Intertek CEA, and most of the cells feeding those lines arrive from overseas.

Intertek CEA estimates a base case of 10 cents per watt added to imported solar cell costs by anticipated Section 232 tariffs. That charge tilts the math toward cells made inside the country, where module makers now lean on foreign supply.

"The U.S. solar market does not need more announcements," ES Foundry CEO Alex Zhu said, adding that it needs operating capacity, proven production and domestic suppliers.

The Greenwood ramp moves ES Foundry from 1 GW to 3 GW of PERC cell output.