In early 2019, a Dissolved Gas Analysis (DGA) was performed on all three single-phase 500 kV: 115 kV transformers at Tono Substation. One of the transformers was identified as nearing its end of life due to increased gassing to high levels After PSE’s need assessment and solution report were completed, planning and engineering worked on a design that led to the procurement of a new, state-of-the-art, transformer at the end of 2020.
Two and a half years later, a