Three years ago, Swissgrid launched the «Pylonian» Internet-of-Things project. This involved placing sensors on pylons to measure variables such as pylon vibrations, pylon inclination, temperature and solar radiation. Swissgrid uses this data to monitor the condition of the transmission pylons. In the reporting year, Swissgrid installed additional types of sensors, particularly weather stations, to help forecast production capacity from renewable energy resources. Swissgrid also implemented «Sensorian», a telecommunication and sensor-independent platform that can host any type of sensor data on the Swissgrid data platform in a scalable, secure and flexible manner. In addition, experiments were conducted to simulate real events in order to link the data collected with potentially dangerous situations. This will allow the system to predict possible dangers so that Swissgrid employees can initiate measures at an early stage to prevent damage to the pylons.
Annual Report
Year in review
IoT project: new sensors and scenarios for monitoring pylons
Swissgrid ensures cooperation with the «Core» region
Switzerland is now part of the capacity calculations for transnational electricity trade in Central Europe. Although this will improve grid stability, it is no substitute for an electricity agreement. Swissgrid has reached an agreement on the joint coordination of cross-border capacities with the grid operators in the «Core» region, which is an association of countries in Central and Eastern Europe. This coordination also concerns the calculation of the capacities required for energy exchange between Switzerland, Austria, Germany and France. Until now, the Swiss grid has not been included in the planning of short-term (day-ahead) energy exchange, for example between France and Germany. Cooperation with the «Core» region will make it easier for Swissgrid to control electricity flows through Switzerland. This will increase grid stability.
Investment, repair and maintenance costs for the grid in 2024
In the reporting year, Swissgrid invested CHF 256.3 million in the renovation and expansion of the transmission system. Swissgrid spent a total of CHF 58.3 million on the repair and maintenance of the transmission system. This work includes the replacement of conductors, the revision of circuit breakers, corrosion protection for supporting structures, avalanche protection and the repair of installations after a damaging event.
Strategic Grid 2040
The grid is the backbone of a secure and sustainable supply of electricity and is essential for the prosperity and high quality of life in Switzerland. Urgent grid development is needed to cope with the growing demand for electricity and increasingly decentralised, volatile power generation. Swissgrid is planning the grid of the future with national and international partners in the energy industry. In the summer of 2024, Swissgrid finished planning the target grid for 2040 and submitted its report to the Electricity Commission for review. The results of this review and the subsequent publication of the Strategic Grid 2040 are expected in Q2/2025.
New control system for the Swiss high-voltage grid
The software used by Swissgrid to control and monitor the Swiss high-voltage grid will have to be replaced over the next few years in order to meet the increasing challenges of grid operations. The new control system consists of three main components: the «SCADA» system monitors and controls Swissgrid’s systems, i.e. the substations and the extra-high-voltage grid. The «EMS Core System» analyses the status of the current grid situation and various scenarios. «EMS Case Builder» creates different scenarios and visualises the results obtained from EMS Core, allowing the System Operation Specialists in the grid control room to anticipate possible developments in the grid.
Digital asset management: more efficient planning, construction and maintenance
Swissgrid will manage the extra-high-voltage grid digitally in the future in order to increase the reliability, capacity and efficiency of the grid. The aim is to increase availability and reduce costs by means of digital asset management. Digitalisation will play a crucial role. A digital grid image (digital twin) will be used to optimise the entire value chain – from planning and construction through to operation. The Asset Management 4.0 program will coordinate all the related projects. Various technological decisions were made in the program during the reporting year. Software solutions will be used to efficiently model asset data, for example.
Digital asset management: greater efficiency thanks to drones
Autonomous drones and artificial intelligence help Swissgrid to optimise the maintenance and operation of the transmission system. Both technologies are digitalising asset management. Drones are used for line inspections to monitor the condition of the grid. In the long term, drones will also provide data during initial inspections following disturbances in order to quickly assess damage so that repair work can start immediately. The inspection images from the drones are scrutinised by experts. To optimise this process, Swissgrid is working with other grid operators to develop AI algorithms that can automatically detect potential damage. Drones ensure safe access to locations that are otherwise difficult to reach, as well as reducing the carbon footprint in relation to conventional methods such as helicopter flights. Following a preliminary study, a two-year pilot phase has been in progress since mid-2023, during which Swissgrid has been preparing the groundwork for potentially expanding its use of the technology.
Procurement of the hydropower reserve for the winter of 2024/2025
In the summer, Swissgrid procured the hydropower reserve for the winter of 2024/25 by carrying out an auction on behalf of the Federal Electricity Commission (ElCom). This reserve is intended to safeguard Switzerland’s supply of energy and is available for use between February and May 2025 if required. The total volume amounts to 250 GWh at an average price of 66.12 euros/MWh. The invitation to tender was issued in three tranches, and bids were reviewed and approved by ElCom.
PV forecasts to ensure grid stability
Swissgrid prepares forecasts several times a day based on publicly available data on the photovoltaic plants installed in Switzerland. These forecasts show the expected PV production capacity with a high regional and temporal resolution. This data can be used for various purposes, for example to analyse imbalances in the balance groups and to counteract them proactively. This will create direct added value for system operation. The next step will be to integrate the forecasts into other applications and to link them to PV measurement data for validation.
Safety: raising awareness about the operation of a critical infrastructure
Swissgrid operates the Swiss transmission grid and is responsible for one of the country’s most critical infrastructures. The safety of Swissgrid’s own employees is a top priority for the company, which is why it places the emphasis on personal protection. In the reporting year, Swissgrid focussed on promoting safe employee behaviour on the road, whether in private vehicles, on their way to work or on business trips. Every year, key topics are defined in various safety areas in order to raise employee awareness about their importance.
Cybersecurity: a new management structure to strengthen information security
As part of the implementation of the Cyber Security 2027 domain strategy, a new management structure for information security was established in the reporting year. Experts in information security and cybersecurity were appointed in all operational areas. These specialists are actively involved in cybersecurity processes to ensure that information security and cybersecurity requirements are taken into account at an early stage both in projects and in the day-to-day operations of the specialist departments. This initiative will enable Swissgrid to address concerns regarding information security and cybersecurity proactively on an ongoing basis.
Human resources: a high level of expertise
Swissgrid has defined the skills needed for the successful implementation of its strategy and conducted a 360-degree assessment to evaluate the level of expertise of employees. This assessment showed that the level of expertise is at an encouragingly high level and that no general measures are required to increase it. Individual development needs are addressed as part of employees’ personal development plans.
Human resources: protection of personal integrity
Swissgrid assumes its responsibility as an attractive employer and has defined the protection of personal integrity in the workplace as a focus topic. Employees and managers were given special training on prevention, behaviour and procedures in the event of a potential breach of personal integrity. Particular emphasis was placed on the personal responsibility of each and every individual.
Human resources: employee survey shows an improvement in all areas
A survey of all Swissgrid employees once again produced very positive results. Firstly, the participation rate was very high. Secondly, Swissgrid was able to improve the results in all areas in relation to the 2022 survey. The further increase in «genuinely satisfied» employees was particularly encouraging. This result is much higher than for comparable companies. Swissgrid conducts its employee survey every two years.
Roll-out of the latest generation of SAP
The «ERP Way Forward» project involved replacing Swissgrid’s previous SAP system with the latest generation of the SAP ERP system. Swissgrid successfully completed the project in spring 2024. «Support SAP Cloud» services were introduced to extend the main functions. Swissgrid was able to simplify the entire system landscape. Various additional systems, such as planning and analysis software, are now integrated into the standard functions. Thanks to this harmonisation, Swissgrid has created the basis for extensively digitalising and mapping the majority of business processes in a single system.
Cooperation between grid operators
As a result of the energy transition, the number of decentralised, flexible energy resources in the grid is growing. The number of photovoltaic plants in Switzerland has experienced a huge rise. Electric vehicles and heat pumps are particularly important on the consumer side. Swissgrid is working with industry partners to develop a joint market for grid and ancillary services in order to coordinate the use of these flexible resources to ensure stable grid operation. After an initial pilot project focussing on data interchange (phase A), the concept was revised in phase B as planned until the end of 2024. The improved concept will now be tested during phase C. The focus will be on market processes, combining simulations and real data.
Renovation of the Mettlen and Lachmatt substations
The Mettlen substation in the canton of Lucerne is an important node for supplying electricity to Central Switzerland. Swissgrid has modernised the transformation system from 380 to 220 kilovolts to ensure that the system will continue to meet grid requirements in the future. Two new 800 MVA transformers were built to replace the existing 600 MVA transformer, more than doubling transformer capacity.
The individual elements of the first transformer, which was commissioned in September 2024, were delivered in the spring via heavy-load vehicles able to transport over 200 tonnes each. In May 2024, Swissgrid started construction work at the Lachmatt substation in the canton of Basel-Landschaft, which is an important node for supplying electricity to north-west Switzerland. This project involves modernising the 380 kV switchgear and adding a coupling transformer to the substation.
Mörel – Ulrichen grid project: conductor installation complete
A new 380 kV line is being built between Mörel and Ulrichen. In 2024, Swissgrid completed the assembly work and installed the conductors between Mörel-Filet and Ernen. According to the current project planning, commissioning will not be possible until the end of 2026 at the earliest, as soon as Valgrid’s new 65 kV substation in Ernen is ready for operation. The line is important so that all the electricity generated by the hydropower plants in the Valais can be transported away from the production sites.
«Grid express» proposal for faster line replacement
An extra-high-voltage line has a service life of around 80 years. Around two-thirds of the transmission system is now between 50 and 80 years old. Since the complete replacement of overhead lines is often subject to a sectoral plan procedure, it can take 15 years or more from the start of planning to the construction of the line. In order to shorten planning procedures, the Federal Council completed the consultation process on a draft bill for the expansion and modernisation of the grids in the reporting year. The «Grid express» proposal, which will be debated by Parliament in 2025, stipulates that a sectoral plan procedure will no longer be required for replacing extra-high-voltage lines on existing routes. This would make the planning period around half as long, which would have a positive impact on the stability of the Swiss transmission grid.
Bickigen – Chippis grid project: delay despite the rejection of complaints
As with the Mörel – Ulrichen grid project, the Bickigen – Chippis project also focuses on transporting energy generated by hydropower. This energy is produced in the Valais and is mostly used in Central Switzerland. The voltage on the Gemmi line between the Bickigen substation in the canton of Berne and Chippis in the Valais therefore needs to be increased from 220 to 380 kilovolts. However, this expansion will also be delayed, and will now take at least another two years. Although the Federal Administrative Court dismissed the majority of the complaints against the project in January 2024, the planning approval dossier was referred back to the Swiss Federal Office of Energy to examine possible solutions for additional noise reduction.
Very high availability of the transmission grid
In the past reporting year, Swissgrid guaranteed an availability of the transmission grid of over 99.9% (previous year also over 99.9%).
Grid operations proved to be challenging in the reporting year. Large snow reserves led to high electricity production from hydropower. On 30 June 2024, Swissgrid registered record-high exports of 8,794 MW. In June, July and August 2024, Swiss spot prices fell below German spot prices for the very first time. High exports from France and imports to Germany dominated the situation across Europe. In the summer in particular, these factors, combined with the shutdown of grid elements for construction and maintenance work, led to congestion in the Swiss grid, which necessitated the use of large amounts of redispatching energy.
Swissgrid recorded an increase in deviations of the system frequency from the setpoint frequency of 50 hertz. This was mainly due to discrepancies between the PV energy actually produced and the forecasts of the lower grid levels. Coordinated procedures therefore had to be put into practice by European transmission system operators on several occasions. Swissgrid and the German transmission system operator Amprion work together as coordination centres to keep the frequency within the standard range throughout Europe.