Trio of Transformers Worth Millions Finally Complete: Third Giant Transformer Arrives at APG's Zaya Substation

Impressive heavy-duty transport

The first two 380/110 kV transformers, each with a capacity of 300 megavolt amperes (MVA), a length of around 13 meters and a height of almost ten meters, were delivered in the second half of 2021 to the Zaya substation, which was still under construction at the time. Three years later, the trio is finally complete: on July 27, the third giant transformer, weighing around 300 tons, was transported by rail from the Siemens plant in Weiz to Hohenau an der March. APG project manager Bernhard Joksch describes the final stage: "On July 30, the transformer embarked upon the last ten kilometers of its journey by special road transport from the train station to the APG substation in Neusiedl an der Zaya. The next day, the transformer was finally unloaded and pulled millimeter by millimeter onto its foundation with the help of guide rails - precision work that took half a day."

Strong connection: 900 MVA feed-in capacity between the regional grid and APG’s Austria-wide transmission grid

The installation will take several months until the transformer will eventually start operating. “From August to December, we will establish a connection between the transformer and the switchgear panel and thus to the Weinviertel line, i.e. to APG's Austria-wide transmission grid,” explains Joksch, describing the function of the converter, which is another name for a transformer. “Like its two predecessors, we will connect the new transformer to the substation of Netz Niederösterreich in the vicinity and thus to the regional electricity grid. From this point on, the transformer will be able to convert the voltage of the clean wind and solar power from 110 kilovolts (kV) to 380 kV so that it can be fed into the APG grid since the Weinviertel line is operated at 380 kV. The transformers are the heart of the Zaya substation, so to speak; they ensure that the renewable energy produced in the Weinviertel region can be distributed and consumed - both in the region and throughout Austria.” The start of operation is scheduled for February 2025. This will provide a total feed-in capacity of 900 megavolt amperes for climate-friendly electricity at the Zaya site and facilitate a secure energy transition.

New infrastructure for the energy transition & security of supply

The Weinviertel line and the Zaya substation were officially put into operation in the fall of 2022. Company spokesperson Christoph Schuh: "The APG investment in the Weinviertel region, which totals over 200 million euros, is making a significant contribution to achieving the energy transition and the electrification of businesses, industry, and society. In addition, the state-of-the-art plants are key for ensuring the secure supply of electricity in Austria and Lower Austria in particular. APG is investing around EUR 445 million in the domestic electricity system across Austria in 2024 alone. To achieve Austria's climate and energy targets, the APG investment will even amount to around nine billion euros by 2034."