US solar module manufacturer SEG Solar has inaugurated a 4GW module manufacturing facility in Tomball, Greater Houston, Texas, taking the company’s total US annual module nameplate capacity to 6GW.
The company described the plant as a major step in its expansion of domestic manufacturing capacity.
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SEG said the facility represents an investment of US$200 million and covers more than 500,000 square feet. The factory is also among the largest heterojunction (HJT) module manufacturing facilities in the country, according to SEG.
Announced in May 2026, the plant houses four production lines dedicated to the company’s latest-generation SIERRA N series HJT modules. The lines are designed to manufacture modules using both 210mm and 210R wafer formats.
SEG said the plant incorporates specialised HJT production processes, including low-temperature soldering and precision butyl sealant application. These processes are intended to improve module reliability and durability while supporting higher long-term energy yields.
Jim Wood, SEG Solar’s CEO, recently spoke with PV Tech Premium about building HJT lines in the US (subscription required) and the company’s overall manufacturing roadmap in the US and in Southeast Asia.
Founded in 2021 and headquartered in Houston, Texas, SEG Solar has shipped more than 7.5GW of modules globally, according to the company. At of the end of 2025, SEG had 6.5GW of annual global module production capacity.
Tomball is SEG’s second US module manufacturing facility. The company commissioned its first 2GW manufacturing plant in August 2024 and shipped its first utility-scale module order from its Texas manufacturing operations to Avangrid in August last year.
Recently, the firm has announced plans for a third US module manufacturing plant, with 4.6GW of annual nameplate capacity, which is expected to take its total operational manufacturing capacity to 10.6GW.
The 1.15 million-square-foot facility was planned for Greater Houston, Texas, with construction targeted for completion by March 2027 and commercial HJT module production scheduled to begin in May 2027.
SEG is also expanding its global manufacturing footprint. The Texas module plant follows the company’s December 2025 announcement of a 3GW ingot and wafer facility in Indonesia, with construction slated to start in Q2 2026.
The Indonesian expansion forms part of SEG’s vertically integrated supply chain, following the commissioning of a 2GW cell facility there in 2025.

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