A new 380 kV connection between Airolo and Lavorgo will replace the existing high-voltage line, allowing greater security of supply for Ticino and Switzerland. The new route is planned on the right side of the valley, away from built-up areas.
Swissgrid plans to replace the existing high-voltage line between Airolo and Lavorgo with a new 380 kV overhead line. The line currently in use was built in the 1950s and no longer meets current needs. The new route is 23 km long and will pass along the more shaded side of the valley, away from built-up areas. Once the work has been completed, the existing line will be dismantled. As a compensatory measure, the AET line to Quinto, Rodi and Faido will be partially cabled.
A SBB 132 kV line will be bundled on the same pylons, which will power the AlpTransit Gotthard railway line.
The line is required to guarantee sufficient energy supply in Ticino and Switzerland. Currently the existing lines in Upper Ticino are inadequate and overloaded, which puts a limit on production at the hydroelectric power plants in Ticino. Swissgrid submitted an application for a construction permit in May 2020, and the planning approval process is still ongoing.
The first consultation for the increase in voltage between Airolo and Lavorgo dates back to 1997, when Atel owned this high-voltage line. In 2006, a decision was made to integrate the FFS line into the project, while in 2012, a support group for the Swiss Federal Office of Energy was established. This support group assessed the cable or partial cable variations. 2013 was a milestone for the project: Swissgrid became the owner of the national electricity grid and the canton launched the «General study on the high-voltage grids of Ticino». This study has led to a total reorganisation of Upper Ticino, which will enable the dismantling of an additional 60km of overhead line. It also confirmed the need for the Airolo – Lavorgo project. In 2015, the support group defined the corridor on the right side of the valley and the technology to be used (overhead line). This recommendation was the subject of a public consultation with local municipalities, held in the summer of 2015. On 23 March 2016, the Federal Council approved the corridor and the technology, and this decision formed the basis for Swissgrid’s subsequent development of the definitive route. Swissgrid submitted the application for a construction permit in May 2020, and the project has been published in the local municipalities in June 2020.
In November 2013, the Canton of Ticino, Swissgrid, AET and Swiss Federal Railways (SBB) jointly decided to carry out a «General study on the high-voltage grids of Ticino» in coordination with the Swiss Federal Office of Energy (SFOE). The aim of this study was to look for variants that would be better suited to the specific characteristics of the area and could be considered part of an overall vision for Upper Ticino rather than simply the Leventina district. In an initial phase, the study examined the zone designated as the «Upper Ticino – Western Part» section, which includes Vallemaggia and Locarnese up to Magadino, Val Bedretto and Upper Leventina up to Lavorgo.
From the 70 possible solutions identified in the study for reorganising the transmission lines, the SFOE and the project support group unanimously chose the «Leventina + 14» variant. Among other things, this solution will relieve valuable areas of more than 70 km of overhead lines, which will be dismantled.
The upgrade project is part of Swissgrid’s Strategic Grid 2025 and is of national importance. Thanks to this new overhead line, a second 380 kV connection will be established between the Canton of Ticino and the rest of Switzerland (in addition to the Lucomagno Mettlen – Lavorgo line), thus improving the energy transmission capacity. A SBB 132 kV line will also be bundled on the same pylons of the new high-voltage line. SBB will therefore have greater security of supply for the AlpTransit Gotthard railway line.
Once commissioned, it will be possible to dismantle the existing 220 kV line that in some places runs close to built-up areas. In addition, as a compensatory measure, the AET 50 kV line will be partially cabled.
The new line will be 23 km long and will run along the right side of the valley. The municipalities involved in the project are Airolo, Quinto, Prato Leventina, Dalpe and Faido. The planned investment is CHF 82 million.
In 2016, the Federal Council approved the planned corridor and the technology to be used (overhead line). Based on this decision, Swissgrid developed the definitive route in collaboration with the municipalities and «patriziati» (public entities managing collective properties), through numerous inspections and constant dialogue with the local authorities. Swissgrid submitted the planning application to ESTI in May 2020. The project was publicised in the municipalities in June 2020 for 30 days. The authorities and private individuals then had the opportunity to submit their objections. It is now up to the Swiss Federal Office of Energy to make a decision on granting the construction permits. This decision may in turn be challenged. In this case, the Federal Administrative Court and the Federal Supreme Court will decide whether the SFOE’s provisions are fair and, in the event of an appeal by the parties affected, whether the law has been correctly applied.
During the sectoral plan process, the transmission technology was examined. Variants as overhead line, full cabling and partial cabling were examined. These variants were evaluated using the evaluation scheme of the Swiss Federal Office of Energy. The aspects environmental protection, spatial development, technical aspects and economic efficiency were examined. On the basis of these assessments, the support group determined the best solution (in the Airolo – Lavorgo project as an overhead line) and this was determined by the Federal Council on 16 March 2016 (SÜL 106).
Due to the cable weights and socket shafts (approx. every 700 – 1000m), the cable route can only be routed in the populated area or mainly in the valley floor. Accessibility must be guaranteed at all times in the event of damage, as the cables would have to be replaced. It was also shown that in the event of a failure, the line would be unavailable for a longer period of time, which in turn weakens the security of supply, especially in Ticino. It should also be noted that if the Swissgrid lines were to be wired, SBB would be built as an overhead line, as cabling is not possible due to resonance frequency.
During the preparation of the construction project, the aspects of the evaluation scheme were checked again to ensure that there have been no significant changes since the Federal Council's decision.
| Voltage | 380 / 132 kilovolt |
| Route length | 23 kilometres |
| Number of pylons | 59 |
| Conductors | Aldrey 1000 and Aldrey 800 |
| Partner | SBB |
The construction of a major infrastructure project such as a high-voltage line will inevitably have repercussions on the surrounding landscape. Swissgrid is committed to mitigating the impact of the line and to compensating for any possible impact. The environmental impact report identified a further 100 nature conservation projects. These measures include the monitoring of the golden eagle and black grouse, as well as the restoration of cascades (such as the Trenta Valli cascade) and the restoration of wooded pastureland for agriculture.
The measures undertaken to benefit nature also include the dismantling of the existing line that currently runs alongside built-up areas, and the partial burial of the AET line. The new high-voltage line will be constructed away from built-up areas and will be located on the more shaded side of the valley.
Bundling the new Swissgrid 380 kV line with the SBB 132 kV line will avoid the requirement to construct two independent sets of pylons – all for the benefit of the landscape. The new pylons will be supplied already painted green so that they blend in with the surrounding woods.
In some areas, clearing will be required, which could make the line slightly more visible for the first few years. Low trees will be planted, making the pylons less visible.
To define the route, Swissgrid decided to talk to the municipalities and «patriziati» (public entities managing collective properties). Numerous inspections and photomontages were carried out, which were then optimised at numerous meetings with the local authorities.
The further the line from the surrounding villages, the less of a burden it will be on the population. The limit of 1 μT for electromagnetic radiation will be complied with at all times or perhaps not even reached. Noise pollution will be notably reduced thanks to the use of the latest technology and two-conductor bundles.
To develop the project, Swissgrid relied on natural hazard experts. For the Tremorgio crossing, for example, an assessment was carried out by the Swiss Federal Institute for Snow and Avalanche Research at Davos. The granting of the construction permit was subject to strict conditions. Some of them involved checking, in collaboration with geologists and engineering firms in the canton, whether protective measures are necessary at the pylons. Potential natural hazards include landslides, debris flows, avalanches and rockfall.
