CEF Energy: optimising grid infrastructure to reduce energy costs

As the world moves towards a more sustainable energy system, the GreenSwitch project is playing a key role in transforming the grid infrastructure in Austria, Slovenia and Croatia. 

Supported by CEF Energy with EUR 73 million, the smart grid project aims to modernise and digitalise the existing grid infrastructure, making it smarter, more reliable and ready to integrate both new technologies for transmission and distribution and renewable energy sources. 

Since its launch in March 2023, GreenSwitch has already started delivering some benefits, such as increased observability and improved control of the grid. Once the project is completed by the end of 2028, cross-border cooperation between the three countries will strengthen electricity markets. The quality, safety and reliability of electricity supply will be also increased, as well as the hosting capacity to integrate renewables and e-mobility in the grid.

Progress in Austria: Strengthening the Grid in Challenging Terrain

Last week, we visited the Austrian side of the project, namely the Carinthia region. The visit helped to grasp the topography-specific challenges that makes electricity distribution complex, as the region is known for its mountainous landscape and long valleys, complemented by spread rural and residential areas that require stable power supply. 

The primary substation of Winklern (110/22 kV), currently under construction, is expected to be completed by the end of 2025. It will help to increase the security of supply for important industries and end-users in the Western side of the region, mitigating the voltage challenges generated by long electrical lines feeding the extensive Western valleys. One more substation of similar characteristics is expected to be completed in the area of Velden (also in Austria) and five more in Slovenia and Croatia. 

Currently, there are more than 20 secondary substations already modernised and equipped with smart devices in Carinthia. These digital upgrades will enable the development of more advanced demand management systems, that can significantly increase security of supply and controllability of the grid, while ensuring to meet customers' evolving needs. 

We visited three of these substations, located in the areas of Föderlach, Reifnitz, and Maria Rain, as they are a clear example of the measures being implemented by the beneficiary Kärnten Netz to prepare the grid for the changing demand patterns outside of big cities, increasing the hosting capacity that enables the integration of home renewable energy solutions, such as photovoltaic panels, electric heating, and e-mobility. This will promote greener behaviours, self-consumption, and reduce carbon footprints and energy costs. Forty more secondary substations will be modernise in Austria during the project life, and more than 300 in Slovenia.

Overcoming Borders and Challenges

One of the most challenging aspects of GreenSwitch is the development of a cross-border emergency power connection at the Loibl Pass, a high mountain pass in the Karawanks chain of the Southern Limestone Alps, linking Austria and Slovenia. Construction is set to begin this year, but the region’s rugged terrain and the logistics of transporting heavy equipment make this a significant challenge.

That said, the beneficiaries and the responsible authorities of both countries see this also as an opportunity to improve not only the power connection but also the overall infrastructure of the tunnel on both sides. Strong cooperation between national authorities and project partners will be essential to overcoming these technical and logistical hurdles.

As GreenSwitch progresses, it becomes increasingly clear that modernising the power grid is crucial for a sustainable and affordable energy future. We’ll continue to follow its development, as projects like this are not just about infrastructure—they are about reshaping how we will generate, distribute, and consume energy for years to come.