Learn more about the Centralia conversion project from answers to frequently asked questions.
1. Why convert Centralia Unit 2 instead of building a new facility?
The project uses existing turbines, transmission and site infrastructure, avoiding new land disturbance, reducing cost and improving timelines compared to building a new facility from the ground up.
2. Why natural gas instead of renewables or battery storage?
Renewables and storage are essential to Washington’s clean energy future. However, current battery technology and renewable generation cannot fully address extended periods of low wind, low solar and low hydro conditions. We expect that the converted unit will operate as a reliability resource to help address the current resource adequacy gap while next-generation technologies continue to mature.
3. How does this project support Washington’s clean energy goals?
The conversion significantly reduces greenhouse gas emissions compared to coal operations. It also:
- Eliminates coal ash and mercury
- Significantly reduces sulfur dioxide (SO₂), nitrogen oxides (NOₓ) and particulate matter
- Reduces water use associated with coal flue-gas scrubbing
- Operates within the existing facility footprint
The project aligns with Washington’s Climate Commitment Act requirements and will include carbon allowance compliance.
4. How often will the converted unit operate?
Under the terms of the commercial agreement with Puget Sound Energy, TransAlta does not dispatch the facility itself but rather will take dispatch instructions from Puget Sound Energy. It is anticipated that Puget Sound Energy will dispatch the converted facility on a limited basis in order to meet the reliability needs in the region. The converted facility will not operate more than 59% in any given year.
This provides operational flexibility to meet system needs while maintaining its intended role as a reliability resource.
5. What is the timeline for the project?
We expect that the converted unit will achieve commercial operation in the second half of 2028.
6. What about the recent U.S. Department of Energy order?
In December 2025, the U.S. Department of Energy issued a temporary order requiring Centralia Unit 2 to remain available for operation for 90 days, through March 16, 2026. As required, TransAlta is complying with the order. TransAlta is also continuing to advance the conversion in order to achieve a commercial operation date of the converted unit in the second half of 2028. The coal-to-gas conversion project remains a priority for TransAlta.
7. What does this mean for workers and the community?
TransAlta remains committed to workers and to the Lewis County community.
- Construction is expected to generate approximately 700 jobs
- Once operational, the facility is expected to directly employ more than 40 people
Through the 2011 Transition Agreement, TransAlta committed more than $55 million to support workers, education, energy efficiency and economic diversification in Lewis County, with over 90 percent invested to date.
Reclamation of former mining lands continues through 2045, with more than 3,200 acres restored and over 1.7 million trees planted since 1991.
8. Will ratepayers cover the cost of the project?
No, the cost of the construction will be borne by TransAlta and will not be directly paid by ratepayers. TransAlta will receive a fixed capacity payment from Puget Sound Energy for the term of the agreement. Puget Sound Energy is seeking to have these payments included within its rates.
9. Is TransAlta considering other future uses for the Centralia site?
Yes. TransAlta is evaluating additional long-term opportunities consistent with Washington’s emission-reduction goals and system needs, including ongoing assessment of regional wind resources.
Have another question for us?
We welcome engagement from community members, employees, Tribal Nations and stakeholders.
Contact TransAlta at [email protected]
