Sarasdorf substation

Millimeter work for the power supply: First large transformer reaches APG substation in Sarasdorf

On Monday evening, the first of two new 380/110 kV large transformers reached the Sarasdorf substation near Bruck an der Leitha (Lower Austria) - a milestone for the expansion of one of Austria's central electricity hubs. Yesterday morning, the 289-tonne steel colossus was pulled onto its foundations with millimetre precision in around four hours. 

The transformer is 11.5 meters long, 3.4 meters wide and 4.6 meters high and has an output of 300 megavolt amperes. It was delivered by rail from the factory in Weiz (STMK) to Götzendorf station and then by road. The investment costs amount to around 7 million euros per unit.

Logistical challenge

"The precise placement of such a giant is logistically challenging: in order to pull it onto its foundation, two special chassis, each weighing around one tonne, were first rolled under the transformer. The transformer was then lowered, bolted to the chassis standing on guide rails and pulled onto the foundation millimetre by millimetre within four hours using hydraulically driven cable hoists," reports Christoph Guldner, who is managing the project for the electricity grid operator Austrian Power Grid (APG). He adds: "The new transformer will be fully upgraded and connected to the switch panels by December. The second one will follow in January - a further step towards completing the expanded system by the end of 2029."

Reliable power supply in the region and climate-friendly energy for the whole of Austria

"Transformers are the heart of every substation. In Sarasdorf, they connect APG's Austria-wide extra-high voltage grid with Netz Niederösterreich's distribution grid, which brings the electricity directly to households and businesses," says APG project manager Guldner. This is important because it means that the Bruck basin can be fed with electricity from APG's Austria-wide grid when needed and supplied reliably. 

Or vice versa: locally generated electricity from wind power and photovoltaics that cannot be consumed is forwarded to other parts of the country. To wherever it is needed. Or to the large storage power plants in the Alps. "The ability to transport electricity generated from renewable energy sources over long distances within Austria reduces dependence on imports from abroad. We are thus making an important contribution to a secure energy transition," says Guldner.

Background: Expansion of the Sarasdorf substation

The Sarasdorf substation is located in the district of Bruck an der Leitha, one of the windiest regions in Austria. The expansion, which has been underway since fall 2024, includes eleven new 380 kV switchgear panels and two large transformers. The aim is to increase the connected load to 900 MW by 2030 - enough to transport up to 18 times more electricity than is consumed in the region.

With a total investment volume of around 200 million euros, APG is working with Netz Niederösterreich to strengthen security of supply and create the conditions for integrating more and more renewable energies into the Austrian electricity grid.

APG to invest nine billion euros in grid infrastructure by 2034

The project is part of APG's nine billion euro investment program to expand and strengthen Austria's grid infrastructure by 2034. A well-developed electricity grid and sufficient substations are the prerequisite for a reliable, affordable energy transition in Austria.

Mast extension with mega crane

Thrill: Mega crane sets pylon in 4-fold line

In the course of the grid expansion and extension of the Sarasdorf substation, it was necessary to dismantle 2 pylons and erect 3 new pylons. After the 4-fold 380 kV line was split into 2 pylons, the old supporting pylon had to be dismantled and a new guyed pylon erected.

Good to know: Guyed pylons are more stable than supporting pylons.

Large-scale fire drill at the Sarasdorf substation

In the video you can see 170 firefighters in action.</p

Safety partnership: APG and Sarasdorf volunteer fire department rehearse an emergency

APG rehearsed an emergency last Saturday, November 16, together with the Sarasdorf Volunteer Fire Department (Bruck/Leitha district, Lower Austria). The exercise involved 170 members of the volunteer fire departments from the entire district and 8 APG specialists. The training site, the APG substation in Sarasdorf, is currently undergoing a €130 million modernization and is being expanded into a central hub for feeding renewable energy into the grid.

In order to be prepared for an emergency, APG cooperates with local fire departments at all its locations across the country. This is also the case in Sarasdorf, where it is currently investing 130 million euros in the expansion of the APG substation. By 2029, 21 additional 380 kV switchgear bays and two new 380/110 kV large transformers will be built here on an area of six hectares. From this date, a total of four transformers will improve the power supply as well as the regional integration and nationwide distribution of climate-friendly wind and solar energy. Each individual transformer will be filled with 90 tons of insulating oil. "Safety is a top priority at APG. In addition to a state-of-the-art extinguishing system in the substation, trusting cooperation with the local emergency services is essential in order to be optimally prepared for a potential fire. Joint exercises are essential for this," emphasizes Sabrina Liebetegger, Head of the APG operating regions.

Large-scale exercise with 170 firefighters

The time had come last Saturday: from 7:45 am to 11:30 am, up to 170 firefighters simultaneously rehearsed an emergency at the Sarasdorf substation. They arrived with a total of 50 fire engines. The training scenario: a 380/110-kilovolt transformer filled with 90 tons of insulating oil catches fire. As there is little extinguishing water available at the Sarasdorf substation, the fire department laid two approx. 2.5 kilometer long supply lines from the nearby Leitha river within 45 minutes during the exercise. To bridge this period, a shuttle service with fire engines between the plant and the fire station ensured that sufficient extinguishing water was available. In addition to firefighting, the exercise included two rescues from manholes as well as the rescue of a missing person and another person from an accident vehicle.

For full details, please see the press release.

Mega hub for renewables: ground-breaking ceremony for 200 million euro project

The electricity grid operators Austrian Power Grid (APG) and Netz Niederösterreich are modernizing and expanding the Sarasdorf substation: The ground-breaking ceremony for the mega project, which will make the site a central hub for the integration of wind and solar energy in Austria, took place today. The multi-million euro investment is also an important step towards a secure energy transition.

Climate Protection Minister Leonore Gewessler and Lower Austria's Provincial Parliament President Karl Wilfing took part in the symbolic ground-breaking ceremony alongside the hosts Gerhard Christiner, Chief Technical Officer of APG, and EVN CEO Franz Mittermayer.

Renewables: From Sarasdorf to the whole of Austria

The Sarasdorf substation is located in the middle of one of the windiest regions in Austria, where the number of photovoltaic systems is also steadily increasing. After all, more than 2,700 PV systems in the district of Bruck alone feed the solar power they generate into the grid. The fact that almost three times as many completed PV systems were registered this year alone as in the same period last year illustrates the trend towards decentralized power generation.

The substation is directly connected to the lines of Netz Niederösterreich via a 110 kV switchgear. The construction of eleven additional 380 kV switchgear panels and two 380/110 kV giant transformers will further strengthen the importance of the APG site near Bruck an der Leitha for the energy transition in Austria. APG is investing around 130 million euros, Netz Niederösterreich around 70 million euros.

Construction site as excavation site: archaeological finds

In the run-up to work on the expansion of the Sarasdorf substation, archaeologists examined the entire construction site for traces of the past. With success: numerous finds from the Bronze Age to the Roman period testify to permanent settlement in the area for over 4,000 years. The visual highlight is a 3,500 to 4,000-year-old jug with a handle.

14 banana boxes and a jug with a handle

Since 2006 - even before the ground-breaking ceremony for the then new Sarasdorf substation - the Federal Monuments Office and archaeological service providers have been continuously carrying out archaeological measures during construction work on the substation site. "In the most recent excavation campaign, which began in September 2021, we discovered a large number of archaeological relics - a total of 14 banana boxes full," reports Maximilian Bergner from Novetus, who is leading the excavations on behalf of APG. Banana boxes are, so to speak, the quantity of archaeologists. Bergner explains: "The most remarkable finds include the remains of Bronze Age and Iron Age settlements as well as an extensive Roman ditch system that surrounds a Roman farmstead discovered in 2014. Particularly vivid is an almost complete, 3,500 to 4,000-year-old vessel: a handled jug from the Wieselburg culture, which we excavated and restored last year."

The substation area is an ideal excavation site

According to Bergner, the site around the Sarasdorf substation fits well into the overall picture of the region in terms of the research findings obtained and he emphasizes: "The APG construction site is one of the few places in Austria that is being investigated over such a large area, namely over 30,000 m². This gives us a good overview of different eras over a period of more than 4,000 years. It also provides an insight into the life and activities of an agricultural settlement in the fertile lowlands of the Bruck Basin." According to the archaeologist, kilns and some clay extraction pits also indicate that the population produced pottery for their own use at the time - such as the jug mentioned above.

The finds will initially remain at Novetus GmbH, where they will be cleaned, conserved and analyzed. They will then be handed over to APG, Christoph Schuh: "It is impressive how many finds our substation site has unearthed over a historically long period of time. The combination of significant investment in infrastructure and the appreciation of the site's cultural heritage underlines our commitment to sustainable development and the preservation of history."

For full details, please see the press release.