02.10.2019 - Axpo, SN Energie and tb.glarus are modernising the grid infrastructure in the Canton of Glarus. Jointly defined measures will sustainably enhance power supply to residents and businesses in the region of Glarus-Schwanden taking environmental aspects into account
Axpo and SN Energie are responsible for the supra-regional grid infrastructure in the Glarus-Schwanden region. Technische Betriebe Glarus (tb.glarus) is in charge of the local distribution grid. The three energy companies are pooling their forces and know-how. In close cooperation they are currently realising various projects to sustainably enhance power supply in the region with an outlook to the future. Joint planning will minimise disruptions for Glarus residents as well as environmental impacts.
Substations are important hubs for transporting electricity. They convert the electrical energy produced in power plants from a higher to a lower voltage level so it can be distributed regionally. The Axpo Löntsch substation connected to the Löntsch hydropower plant is an important supply hub in the Glarus region. The outdated facility will now be completely upgraded.
The existing 50-kV air-insulated infrastructure upstream from the Löntsch power plant will be replaced with new, compact, gas-insulated 110(50)-kV switchgear. Gas-insulated switchgear, which uses a special gas in lieu of air as the insulation medium, enables more compact construction in comparison to outdoor substations. The new facility will be housed in the former Löntsch power plant powerhouse. The old outdoor substation and building will be dismantled after commissioning of the new facility. In addition, existing transformers will be replaced with new units. Construction is scheduled to start in 2020. The upgraded Löntsch substation is expected to go into operation with 50 kV in 2022 and converted to 110 kV in 2025. At the same time, SN Energie is upgrading the Schwanden substation so that it will be ready for operation with 110 kV in 2025.
In order to continue accommodating rising power demand in the future, Axpo is gradually converting its entire supra-regional distribution grid from 50 to 110 kV. The voltage increase improves grid efficiency and reduces energy losses. SN Energie's existing 50-kV overhead line will be replaced with 110-kV underground cabling between the Löntsch and Schwanden substations. Axpo's two 16-kV overhead lines will be partially replaced with underground cabling from the Löntsch substation to supply the town of Glarus. Axpo and SN Energie are taking advantage of synergies and bundling their power lines into a common cable channel. In total, 42 power masts will be removed, which will significantly improve the landscape in the Glarus region. Work will begin in 2020 and is expected to be completed by 2022. Planning permits for the new lines have not yet been issued.
tb. glarus strives to develop grid infrastructure based on future needs for efficient local energy supply. The entire feed-in and energy concept for the medium-voltage grid will be revised. An important goal is to reduce the number of feed-in points on the 16-kV level, and to decrease the number of measurement points in the entire medium-voltage grid from 13 today to 5 in the future. This reduction makes optimal grid switching conditions possible, which in turn creates efficient, reliable grid protection. The new grid concept will also optimise construction costs and reduce maintenance expenses. Resource optimisation combined with improved safety for the benefit of the population and technology continue to be the ultimate goals of tb.glarus.