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TransAlta News Release TransAlta Reports Strong First Quarter 2021 Results led by Exceptional Performance at Alberta Hydro CALGARY , Alberta ( May 13 , 2021 ) First Quarter 2021 Highlights • • Comparable EBITDA ( 1 ) of $ 310 million , an increase of $ 90 million or 41 per cent compared to the same period in 2020 Free cash flow ( " FCF " ) ( 1 ) of $ 129 million or $ 0.48 per share compared to $ 109 million or $ 0.39 per share , a 23 per cent increase on a per share basis , for the same period in 2020 Hydro segment delivered $ 77 million of comparable EBITDA , an increase of $ 51 million or 96 per cent compared to the same period in 2020 Adjusted availability was 88.6 per cent compared to 92.8 per cent for the same period in 2020 Other Highlights • • . • • On Dec. 31 , 2020 , all power purchase arrangements ( " Alberta PPAs " ) with the Alberta Balancing Pool for TransAlta's Alberta Hydro facilities , Keephills Units 1 and 2 and Sheerness Units 1 and 2 , expired and these facilities began fully merchant operations in the Alberta electricity market Completion of Sundance Unit 6 and Sheerness Unit 1 conversions to gas - fired generation Commenced gas conversion of Keephills Unit 2 with planned completion during the second quarter of 2021 Windrise wind project construction was 84 per cent complete as of March 31 , 2021 Extended $ 1.25 billion Syndicated Credit facility to June 2025 and converted the facility into a Sustainability Linked Loan aligning the cost of borrowing to TransAlta's greenhouse gas emissions reductions and gender diversity targets Subsequent Events & Updates • • Launched 130 MW Garden Plain wind project with an 18 - year power purchase agreement with Pembina Pipeline Corporation for 100 MW of renewable electricity and associated environmental attributes Completed 10 - year contract extension at Sarnia cogeneration facility with large industrial off - taker • Settled the litigation with Mangrove Partner's Master Fund Ltd. TransAlta Corporation ( " TransAlta " or the " Company " ) ( TSX : TA ) ( NYSE : TAC ) today reported its financial results for the quarter ended March 31 , 2021 . " TransAlta delivered excellent results during the first quarter , ahead of our financial expectations . Our strong performance was led by our Alberta Hydro fleet as we experienced the first few months of fully merchant operations in the Alberta electricity market . Our strategically diversified fleet of hydro , wind , energy storage and thermal assets demonstrated its competitiveness and continued value in the new market structure , " said John Kousinioris , President and Chief Executive Officer . " Our Energy Marketing segment also had an exceptional start to the year with favourable