TransAlta Provides Notice to Mothball Sheerness Unit 1

CALGARY, Alberta, Dec. 18, 2025 (GLOBE NEWSWIRE) -- Alberta Power (2000) Ltd., a subsidiary of TransAlta Corporation (TransAlta or the Company) (TSX: TA) (NYSE: TAC), provided notice to the Alberta Electric System Operator on December 18, 2025, that Sheerness Unit 1 will be temporarily mothballed effective April 1, 2026, for a period of up to two years. TransAlta maintains the flexibility to return the mothballed unit to service when market fundamentals or contracting opportunities are secured. The unit will remain available and fully operational through the winter season and Sheerness Unit 2 will remain fully in service.