The aged transformer Abstract/summary

Given the conditions prevalent in those days, transformers put into service throughout the 60s, 70s and 80s of the previous century were expected to last anywhere between 20 – 25 years in the case of the unit-connected transformers, and anywhere between 30 – 35 years in the case of the network transformers. After that time the transformers were expected to be replaced by new, state-of-the art units. However, we have been seeing dramatic changes take place in the past decade or so, brought about by the current economic situation and the ongoing liberalization of the energy markets. With investments of any magnitude practically out of the question, the issue we are currently faced with is how to use the systems presently in place in the best and most efficient manner possible.