All around the world, grid operators are being confronted with the same challenge: the fact that their equipment is reaching old age. It is no longer uncommon to see power transformers with a service life of 50 years or more. Therefore, there are questions that every grid operator is faced with: What condition is my fleet in? How long will our transformers last, and when will we have to invest in new ones? This situation is aggravated by fluctuating, higher loads resulting from renewable energy sources that increasingly push crucial transformers that are needed to ensure a stable power supply to their limits.