Last week, Calgary-based TransAlta announced that it was shutting down 3 of its natural gas power plants and ending its coal mining operations.
One of the plants—Sundance Unit 5—was previously a simple-cycle natural gas-fuelled plant. TransAlta had planned to convert the plant to a combined-cycle natural gas-fuelled plant by installing 2 new
natural gas combustion turbine generators, as well as 2 heat recovery steam turbine generators.
An in-depth evaluation and assessment of the repowering project, however, revealed that escalating costs, changing supply and demand dynamics, forecasted power prices in the Alberta market, and risks associated with the evolving regulatory environment threatened the project’s viability. So the company suspended the project instead.
In their announcement, TransAlta indicated that they plan to reinvest capital for this project into renewable energy projects instead.
The other two power plants—Keephills Unit 1 and Sundance Unit 4—had been coal-fired plants, and the company was in the process of converting them to natural gas.
According a statement published by the Alberta Electric System Operator the same day as the above announcement (but presumably prior to it), TransAlta has planned to end its coal mining operations by the end of this year. The company had previously promised to end all coal-fired electricity generation by the end of 2021.
The conversion of these 2 plants to solely natural gas wasn’t going to be complete by the end of the year, so TransAlta had initially planned to reduce their power output to 25% of the current output, as a result of the limited natural gas capabilities at the facilities.
Later that day, TransAlta informed the AESO that they’d instead simply shut down Keephills Unit 1 at the end of the year and Sundance Unit 4 next April. This decision came after the company assessed future market conditions, the age and condition of these power plants, and their new focus toward customer-centred renewable energy solutions.
TransAlta plans to invest $3 billion in the next 4 years towards “delivering 2 gigawatts of incremental renewables capacity”.
In the first 9 months of 2021, they’ve already announced renewable energy projects with a cumulative output of 800 megawatts: 300 megawatts in new projects and 500 megawatts in existing projects that they purchases.
They also plan to reduce company emissions by 70% of 2005 levels within the next 8 years and be completely carbon neutral by 2050.