TotalEnergies Becomes Operator of PEL 83

Toronto & London, September 3, 2026 - Sintana Energy Inc. (TSX-V: SEI, AIM: SEI, OTCQX: SEUSF) ("Sintana" or the "Company") is pleased to announce the completion of the previously announced transaction between TotalEnergies and Galp Energias, under which TotalEnergies has acquired a 40% operated interest in Petroleum Exploration Licence 83 ("PEL 83"), home to the giant Mopane discoveries in Namibia's Orange Basin.

PEL 83 is now held by TotalEnergies (40% as operator), Galp (40%), NAMCOR (10%) and Custos Energy (Pty) Ltd. ("Custos") (10%). Sintana maintains an indirect 49% interest in Custos, providing the Company with an effective 4.9% interest in PEL 83.

The Mopane discoveries have a current 3C resource estimate of approximately 1.3 billion barrels equivalent. As operator, TotalEnergies has indicated it plans to initiate a 3-well exploration and appraisal campaign on PEL83 in 2026. This is in anticipation of a potential final investment decision in relation to a phase 1 development in 2028, targeting first oil production in 2032.

Robert Bose, Chief Executive Officer of Sintana Energy, said: "The completion of TotalEnergies' entry into PEL 83 marks a defining milestone for Mopane, for the Joint Venture and for Sintana. With one of the world's premier deepwater operators now driving a three-well exploration and appraisal campaign commencing in Q4 2026, the full scope of technical and financial resources has been coalesced to accelerate this asset toward development. For our shareholders, this transaction sharpens the read-through from Mopane's growing resource base to tangible value in our indirect interest. We look forward to the upcoming activity on PEL 83 to further define and illuminate its potential, and the progress towards FID. Together with upcoming activity on our additional licenses in Namibia and Uruguay, we are positioned across the Atlantic margin for significant progress in the coming quarters".

Sintana remains committed to supporting the responsible development of Namibia's resources for the benefit of its people, including through its indirect interest in Custos, a proudly Namibian company, and to the opportunities this partnership creates for local capacity building and broad-based benefit.