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TM TransAlta News Release TransAlta Reports Outstanding Second Quarter 2021 Results and Increases Annual Guidance CALGARY , Alberta ( August 10 , 2021 ) Second Quarter 2021 Highlights • • • Comparable EBITDA ( 1 ) of $ 302 million , an increase of $ 85 million or 39 per cent compared to the same period in 2020 Free cash flow ( " FCF " ) ( ¹ ) of $ 138 million or $ 0.51 per share compared to $ 91 million or $ 0.33 per share , a 52 per cent increase over the same period in 2020 Hydro segment delivered $ 96 million of comparable EBITDA , an increase of $ 67 million compared to the same period in 2020 Alberta Thermal segment delivered $ 85 million of comparable EBITDA , an increase of $ 55 million compared to the same period in 2020 Adjusted availability was 84.8 per cent compared to 91.5 per cent for the same period in 2020 , largely impacted by planned major maintenance events in the quarter Other Highlights • Windrise wind project construction was 88 per cent complete as of June 30 , 2021 • • Launched 130 MW Garden Plain wind project , 100 MW of which are contracted to Pembina Pipeline Corporation under an 18 - year power purchase agreement Closed the sale of the Pioneer Pipeline to ATCO Gas and Pipelines Ltd. with net cash proceeds of approximately $ 128 million , resulting in a gain on sale of $ 33 million Executed a 10 - year contract extension at Sarnia with one of its large industrial customers Subsequent Events & Updates • • Completed another milestone in our phase - out of coal with the completion of the coal - to - gas conversion of Keephills Unit 2 Reached agreement to construct the 48 MW Northern Goldfields Solar and Storage Project to deliver renewable electricity to BHP Nickel West Pty Ltd. ( " BHP " ) 2021 Revised Outlook With exceptional year - to - date results , the Company has increased its 2021 outlook as set out below : • Comparable EBITDA range of $ 1.1 to $ 1.2 billion • FCF range of $ 440 to $ 515 million • Energy Marketing gross margin contribution range of $ 170 to $ 200 million