X0202 SCHEDULE 13D/A 0001140361-24-050502 0002047012 XXXXXXXX LIVE 5 Common Stock, par value $0.01 05/21/2026 false 0001992243 35834F104 T1 Energy Inc.

1211 E. 4th Street Austin TX 78702

Catherine Pan-Giordano Esq. (212) 415-9200 51 W. 52nd Street New York NY 10019 Anthony Epps Esq. (303) 352-1109 1400 Wewatta Street Denver CO 80202 0002047012 N Trina Solar (Schweiz) AG OO V8 30652664 0 30652664 0 30652664 N 11.0 CO Percent of class calculated based on 279,271,380 shares of common stock of the Issuer outstanding as of May 8, 2026, as reported by the Issuer on the 10-Q filed with the Securities and Exchange Commission on May 12, 2026. Common Stock, par value $0.01 T1 Energy Inc. 1211 E. 4th Street Austin TX 78702 Trina Solar (Schweiz) AG ("Reporting Person") Birkenweg 4 Wallisellen, Switzerland 8304 The Reporting Person is engaged in the business of investment. Under the Cooperation Agreement dated December 23, 2024, upon meeting certain conditions, the Reporting Person was entitled to designate at least one "Trina Director" and did so on December 23, 2024. On December 29, 2025, the Issuer and the Reporting Person entered into an Amended and Restated Cooperation Agreement removing that appointment right, and the Trina Director resigned on March 30, 2026. Accordingly, from December 23, 2024, to March 30, 2026, the Reporting Person was deemed to be a deputized director of the Issuer. N/A - None N/A - None Switzerland Proceeds of sale allocated to working capital of Reporting Person. On May 21, 2026, and May 22, 2026, the Reporting Person sold a total of 22,500,000 shares of common stock of the Issuer in the ordinary course of business. 11.0% Sole voting power: 30,652,664 Shared voting power: 0 Sole dispositive power: 30,652,664 Shared dispositive power: 0 On May 21, 2026, the Reporting Person sold 13,000,000 common shares of the Issuer (the "Shares"), as set forth below: 8,849,024 Shares at an average weighted price of $8.6229 per share, with sales prices ranging from $8.07 to $9.06, inclusive 1,150,976 Shares at an average weighted price of $9.2011 per share, with sales prices ranging from $9.07 to $9.43, inclusive 3,000,000 Shares at an average weighted price of $8.708 per share, with sales prices ranging from $8.61 to $8.96, inclusive On May 22, 2026, the Reporting Person sold 9,500,000 Shares, as set forth below: 9,479,904 Shares at an average weighted price of $8.1347 per share, with sales prices ranging from $7.74 to $8.72, inclusive 20,096 Shares at $8.80 per share N/A N/A Exhibit 10.1 Cooperation Agreement dated as of December 23, 2024 Exhibit 10.2 Amended and Restated Cooperation Agreement dated as of December 29, 2025 Exhibit 10.1 - Incorporated by reference to Exhibit 10.5 to Schedule 13D filed with the Securities and Exchange Commission on December 27, 2024, and incorporated by reference to Exhibit 10.4 to the Form 8-K filed with the Securities and Exchange Commission on November 6, 2024 Exhibit 10.2 - Incorporated by reference to Exhibit 10.1 to the Form 8-K filed with the Securities and Exchange Commission on December 30, 2025 Trina Solar (Schweiz) AG /a/ Vincenzo Costanzelli 05/26/2026