Austrian Power Grid (APG): Construction Project "New Leoben Connection" on Schedule

About halfway through the implementation, APG, Energie Steiermark, and voestalpine AG invited guests to the site of the new Leoben substation, which is currently under construction, to get an impression of the work progress. The excursion was attended by Gerhard Christiner, Spokesman of the Management Board and Chief Technical Officer of APG, Martin Graf, Director of the Management Board of Energie Steiermark, Franz Kainersdorfer, Member of the Management Board of voestalpine AG and Head of the Metal Engineering Division, Gerald Deutschmann, President of the Styrian Parliament (representing Styrian Governor Mario Kunasek), Markus Kraxner, District Governor of Leoben, and the mayors of the two project municipalities Kurt Wallner, Mayor of Leoben, and Wolfgang Gomar, Mayor of St. Peter-Freienstein.

New Leoben connection strengthens Styria as an industrial location and ensures the security of supply in the region

The entire ‘New Leoben Connection’ project will create the necessary capacities to make sustainably produced and low-cost electricity available for local businesses and industry, in particular for electricity-based steel production in the future. This will secure the Leoben region as a strong business location in the long term. Additionally, the new Leoben substation will provide an extra level of grid support for the regional distribution grid, thus enhancing the security of supply in Styria.

Gerhard Christiner, CTO of APG: "With the new Leoben connection, we are not only creating the basis for the electrification of industrial processes and the availability of sustainable and low-cost electricity in the region, but we are also strengthening the regional security of supply. This highlights the importance of our investments, and I am therefore very pleased that we are right on schedule with the construction work. The planned completion in 2026 will be a milestone for decarbonization and Austria as an industrial location. The 118 million euros invested in this project will not only create regional added value, but will also facilitate a secure and affordable energy transition."

Franz Kainersdorfer, Member of the Management Board of voestalpine AG and Head of the Metal Engineering Division: "With greentec steel, voestalpine has a clear step-by-step plan for converting to net-zero steel production. From 2027, the first step will be to replace one blast furnace each at the Linz and Donawitz sites with a green-electricity-based electric arc furnace. This will make it possible to reduce CO₂ emissions by around 30% by 2029 compared to 2019. However, the basic prerequisite for this is that sufficient electricity from renewable sources is available at economically viable prices. Even more important is the provision of an efficient and integrated grid infrastructure. In the specific case of the Donawitz site, this is being achieved with the 'New Leoben Connection' project. With the expansion of the grid infrastructure now progressing rapidly, we are confident that it will be possible to implement the next steps of our greentec steel project on time, so that the first green electricity-powered electric arc furnace can go into operation in Donawitz in 2027."

Martin Graf, CEO of Energie Steiermark: "By 2035, Energie Steiermark is investing around EUR 5.5 billion in the energy transition. This project is an important milestone for a sustainable energy supply in the future that will strengthen Leoben as a business location. With the expansion measures of our project partners, we are building a new substation, which, in addition to increasing feed-in capacities, will significantly increase the security of supply in the region."

Gerald Deutschmann, President of the Styrian Parliament:  "The 'New Leoben Connection' is a forward-looking project that not only strengthens the competitiveness of Styria as a business location, but also makes an important contribution to the energy transition. Grid expansion is a key issue for our energy industry. Secure and efficient transmission can only be guaranteed with an efficient infrastructure. With this connection, we are creating the conditions for an energy-efficient and sustainable development of the region."

Technically demanding construction work

A central element of the project is the construction of the new Leoben substation. A complex terraced construction site (height difference between the different plateaus approx. 6m) had to be built into a slope. As a result, many technical challenges had to be overcome to ensure the safety of the site. The upper retaining wall, an in-situ concrete wall with a ribbed structure and permanent grouted anchors, has an inclination of 75 degrees and a height of up to 20m. 189 anchor bolts had to be inserted into drilled holes of up to 37m depth. The lower retaining wall, also with a height difference of up to 20m, is a reinforced earth wall. A total of approx. 170,000 m³ of fill material - the equivalent of around 70 Olympic swimming pools – was needed for this.

Currently, the construction of the operations building and the hall for the indoor switchgear with a cubage of approx. 25,000 m³ is approaching completion. The installation of the switchgear will begin in November 2025. The first transformer with a capacity of 220,000 kVA will be delivered at the beginning of 2026. Full commissioning of the new substation is scheduled for the summer of 2026.

Expansion of the Hessenberg substation

At the Hessenberg substation (municipality of St. Peter-Freienstein), the 220 kV switchgear is currently being expanded by four new 220 kV switch panels, increasing the number of switch panels from the current 12 to a total of 16. Most of the construction work has already been completed. Following the erection of the steel structures, the electrical system components are currently being installed.

The construction of the line gantries, which enable the transition from the overhead lines to the substation, has already been completed - an important technical milestone that was reached in May 2025. A partial start of operation of the extended switchgear is planned for the end of October 2025.

Line (re)construction and relief of residential areas

Parallel to the work in the two substations, the line work, which covers a length of 6.7 kilometers (4-system: 3.4 km, 2-system: 3.3 km), also began in the spring of 2025. Preparations for the total of 25 pylons are in full swing, with six pylons already under construction upstream of the Hessenberg substation.

In the future, a four-system 220 kV line will run from the four new switch panels in the Hessenberg substation to pylon number 11 in the first line section (around 3.4 km). The two existing systems will then continue to the Ternitz substation. The remaining two systems branch off in the direction of Leoben and run via the voestalpine area to the Leoben substation (around 3.3 km).

The design as a 4-system line means that the first 2.3 km long line section of the existing 220 kV line in the direction of Ternitz - in the area of Hessenbergstrasse and Traidersbergstrasse - can be dismantled, which will noticeably relieve the adjacent residential area. 

About Austrian Power Grid (APG)

As independent transmission system operator, Austrian Power Grid (APG) is in charge of ensuring the security of the electricity supply in Austria. With our high-performance and digital electricity infrastructure and the use of state-of-the-art technologies, we integrate renewable energies, we are the platform for the electricity market, and we provide access to reasonably priced electricity for Austria’s consumers, thus creating the basis for Austria as a supply-secure and future-oriented industrial and business location and place to live. The APG grid totals a length of about 3,500 km and is operated, maintained, and continuously adapted to the increasing challenges of the electrification of businesses, industry, and society by a team of approximately 900 specialists. 67 substations are distributed all over Austria, and the majority are operated remotely from APG’s control center in Vienna. Thanks to our committed employees, Austria had a security of supply of 99.99 percent also in 2023 and thus ranks among the top countries worldwide. Our investments of 650 million euros in 2025 (2024: 440 million euros, 2023: 490 million euros) are a motor for the Austrian economy and a crucial factor in reaching Austria’s climate and energy targets. Until 2034, APG will invest a total of approximately 9 billion euros in grid expansion and renovation projects.