Case study

Process automation and optimization for high voltage overhead line and underground cable planning

Axpo DSO Switzerland

Axpo DSO Switzerland - Process automation and optimization for high voltage overhead line and underground cable planning


Gilytics provides Pathfinder, a cloud solution developed with over ten years of research at the Swiss Federal Institute of Technology ETH in Zurich, which is used by utilities globally.

Pathfinder offers advantages including improved quality when identifying corridor variants based on cost, environmental and technical parameters. Shorter routes can be identified while minimizing the impact on residential areas.

Digitalization is a key priority on Axpo’s strategic agenda. The leading renewable energy player seizes opportunities created through latest technologies and digital transformation to further improve managing their assets as well as to develop their businesses.

Pathfinder allows Axpo to effectively evaluate the best line corridor for overhead and cable variants. Axpo uses the innovative software platform from Gilytics to deliver state-of-the-art engineering support for their distribution grid. Close collaboration with Gilytics was a key success factor, helping to further develop the platform to meet Axpo’s needs.

Axpo is Switzerland’s largest producer of renewable energy and an international leader in energy trading and the marketing of solar and wind power. 5000 employees combine experience and expertise with a passion for innovation. Axpo develops innovative energy solutions based on state-of-the-art technologies for its customers in over 30 countries in Europe, the USA and Asia.


New grid connections, new or adapted power line routes and higher transmission capacity are needed to meet growing electricity demand. This is especially challenging in heavily built-up areas or in protected regions with many regulatory constraints.

Laws in Switzerland strictly regulate protection against risks due to non-ionizing radiation as well as landscape and environment protection. Nonetheless, Axpo is legally required to keep the investment costs low.

In built-up areas, many properties and infrastructure must be considered as well as environmental constraints. Regulations define the minimal distances from a powerline to different obstacles such as residential or non-residential buildings. The integration and optimal placement of substations in such areas close to the existing grid is an additional challenge. All these planning logics need to be considered and mapped out in Pathfinder to find best routing solutions.

These factors and constraints among many others are modeled and visually represented in Pathfinder by using digital maps describing land features.

Automated building classification - Pathfinder
Picture 1: Automated building classification ensures that minimal regulatory distances are maintained
red = non-residential / petrol = residential


110 kV overhead line and underground cable routes were analyzed using Pathfinder in two projects. Axpo has benchmarked their established methods to find line corridors against the new approach provided by Pathfinder.

An automated and fast import of spatial data forms the basis for the evaluation of corridors and routes. Pathfinder provides a large dataset of GIS data available from Swisstopo and other public data providers. This facilitates the access, collection and importing of data. Classifications can also be automated as shown in picture 1. The team also manually added additional GIS data to Pathfinder.

Swiss topo gives free access to official GIS data with 150 data layers of Switzerland.

Parameters in Pathfinder are set according to Axpo’s data model. Corridors and risk heat maps are then generated to compare different route alternatives.

The first projects included the data model, line planning logic and comparing results from more traditional methods with results from Pathfinder. Route options and analytics for each scenario were compared, and model and design edits made to find the best option. The results were exported for further analysis in combination with other tools.

comparing two 110kv line options - pathfinder
Picture 2: Screenshot Pathfinder comparing two 110kv line options
yellow = overhead line / black = earth cable


  • Automated GIS data import from Swisstopo as well as fast and multiple routing functions allow efficient corridor planning of overhead and underground cable lines.
  • The routing provided by Pathfinder is non-discriminating and unbiased. This aspect helps to better explain and clarify the selection of corridors to authorities and stakeholders.
  • Pathfinder allows efficient comparison of path corridors and finds the most economic and technical options. The options can automatically be quantified, analyzing length, costs, the number of pylons for example and visualized both in 2D and 3D.
  • Processes are improved with automated GIS data import from Swisstopo, while regulatory constraints are set and visualized for optimal routing, route comparison, easy editing and reporting.
  • Time can be saved in the design and routing process by combining overhead line and underground cable planning in one tool.

More (in German)

Gilytics allowed us to challenge our current way of working in our digitalization process. The close collaboration helped us to build up knowledge and improve our engineering services. This is another step forward to drive the transition to a clean energy future.

Axpo Grid AG / DSO Switzerland

Thomas Frey

Head Projects and Offers