Since July 23, 2025, electricity has been flowing at the Matrei substation. For a total of 46.5 million euros, Austrian Power Grid AG (APG) and TINETZ-Tiroler Netze GmbH (TINETZ) have installed a 380kV and a 110kV switchgear, and a 380/110kV transformer connecting the two grid levels to ensure a sustainably secure power supply in the Isel Valley and throughout East Tyrol. In addition to the Lienz substation, the system provides a second connection between the Tyrolean 110 kV grid and the Austria-wide APG grid, significantly improving the outage security of the power supply in the region. Furthermore, the surplus electricity generated in the Isel Valley from small-scale hydropower and PV systems can be better transported, which means that the project is also important for the energy transition in Tyrol and Austria.
After a good two years of construction, APG project manager Wolfgang Ranninger and his TINETZ counterpart Stefan Schupfer are delighted with the productive teamwork of all colleagues and suppliers that led to the successful commissioning of the substation: "It's a great feeling when eventually electricity flows through a system that so many people have worked on. We have not merely installed technological equipment, but facilitated a reliable power supply for an entire region."
“365 tons of supply security”
The heart of the new substation is a 380/110 kV transformer, which was delivered to Matrei last April by heavy load transport, first by rail and then by road from Lienz. Within two months, the other elements, such as the cooling system, oil expansion tank, and high-voltage bushings, were assembled. In the course of this work, the transformer, which originally came from another APG site in Burgenland, was also “a little bit overhauled” to adapt it to its new workplace: minor adjustments for the new foundation, replacement of wearing parts and refilling with 110,000 liters of insulating oil were necessary to make it fit for its job over the next 40 years. Ranninger: "We turned 236 tons of transport weight into 365 tons of supply security. The transformer is the heart of the new substation - robust, powerful, and equipped for the coming decades."
Austria-wide coordination, ramp-up voltage from Kaprun
"The commissioning of a large transformer is a highly complex process that has to be meticulously planned and coordinated with internal departments and the distribution grid operator, as well as taking into account the condition of the entire APG grid," says Ranninger, emphasizing: "The cooperation with TINETZ was close and based on partnership right from the start - from the planning phase to the final test of function." The date for the start of operation was set two years in advance and coordinated with the rest of the grid to ensure a smooth transition.
To integrate it in the high-voltage grid, the transformer was connected to the higher-level APG grid via the newly constructed 380 kV switchgear with disconnectors, circuit breakers, and stranding. Finally, on July 23, a generator at the Kaprun power plant was used to carry out the so-called "high-voltage test" - a controlled ramp-up to an operating voltage of max. 420,000 volts, which took around five hours and ensured that the electricity could finally flow in the substation. The fire department was on site with a fire engine and five firefighters in order to be able to intervene immediately in the unlikely event of an incident.
TINETZ renews 110 kV switchgear
The connection to the Austria-wide transmission grid and the resulting significant grid support for the region also required extensive construction work in the existing substation by the project partner, the local distribution grid operator TINETZ. The 110,000-volt outdoor switchgear was replaced by a compact indoor switchgear and expanded to meet the new requirements.
Already at the end of June, the existing 110 kV overhead line was integrated into the new TINETZ system, so that, in the final step, the 110 kV distribution grid could be connected to the transmission grid via the 380/110 kV transformer.
TINETZ emphasizes that it was only due to the intensive partnership and cooperation with APG throughout all project phases and challenges that the grid connection could be implemented at the existing site in such a short time.
The total costs for this measure amounted to 46.5 million euros and will be borne by TINETZ. Over the next 5 years, further investments of 700 million euros in the grid infrastructure, supply reliability, and decarbonization of the electricity system in Tyrol are planned.
Creation of value through domestic expertise
To integrate the 380 kV line between the Lienz and Tauern (Kaprun) substations, which previously ran past the site, APG had a 380 kV electricity pylon erected at the new plant site, in a confined space and within a tight time frame. The work was carried out by twelve fitters of Cteam Österreich Leitungsbau GmbH from Matrei who assembled the 70-ton steel lattice structure using a 160-ton truck-mounted crane. Finally, the conductor cables were installed and connected to the new transformer station.
APG plans to build 65 additional transformers across Austria by 2034
Projects like this are the key to the secure decarbonization of the electricity supply. The APG grid development plan envisages the construction of 65 additional transformers by 2034. Over this period, the Austrian TSO will invest a total of nine billion euros in the expansion and conversion of the grid infrastructure and its digitalization to make all players in the energy system available for operational management (flexibilities) in the future. This will increase the security of supply for society, businesses, and industry in Austria and facilitate the energy transition and the electrification of all areas of life.
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 and reduce the dependency on electricity imports, we are the platform for the electricity market, and we provide access to reasonably priced electricity and thus create 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 1,000 specialists. 67 substations are distributed all over Austria, and the majority is operated remotely from the headquarters in Vienna. Thanks to our committed employees, Austria had a security of supply of 99.99 percent also in 2024 and thus ranks among the top countries worldwide. Our investments of 630 million euros in 2025 (2024: 440 million euros, 2023: 490 million euros) are a motor for the Austrian economy and a crucial factor for achieving Austria's energy targets. APG will invest a total of around 9 billion euros in grid expansion and modernization measures by 2034.
About TINETZ
With around 560 employees, over 12,000 km of lines, 51 substations, and around 4,300 transformer stations, TINETZ-Tiroler Netze GmbH is the largest distribution system operator in Tyrol and reliably and cost-effectively supplies the population and economy, as well as a large number of electricity companies in the province with electricity via over 252,000 withdrawal points. TINETZ plans to invest 3 billion euros in the grid infrastructure, supply reliability, and decarbonization of the electricity system in Tyrol by 2040.
Press contact
Fritz Wöber
