Supporting the modernisation of its electricity distribution assets is a permanent commitment of Viesgo. In order to make our installations more efficient, increase the quality and safety of supply in Asturias, and decrease environmental visual and acoustic impact, Viesgo plans to invest 14 million euros in the comprehensive refurbishment of the Santa Cruz de Mieres substation.

Santa Cruz is Viesgo Distribución’s main substation in the central area of Asturias and plays a key role in the supply of electricity to the municipalities of Aller, Mieres and Lena. The facilities are shared with those of the former Santa Cruz Thermal Power Plant, the initial buildings of which date back to 1913. They were subsequently extended in successive stages and partially dismantled when they were decommissioned, until they reached their present appearance. 

The Regional Government of Asturias has already approved the work, and all that remains is approval of the urban development plan by the Regional Urban Development and Planning Commission of the Regional Government of Asturias and the Local Council of Mieres. 

Santa Cruz de Mieres substation currently consists of 3 voltage levels: 132, 30 and 12 kV. The 132 kV installations, which use conventional technology, are located outdoors and are connected to other Viesgo substations in Cantabria and Galicia, configuring a meshed network at this voltage level. 

Implementation of the Santa Cruz de Mieres project

The project is to be completed in phases. The first includes the refurbishment of the current 132 kV outdoor installations, replacing them with more modern installations with GIS technology, shielded switchgear with SF6 insulation, and the installation of 3 new 132/30 kV transformers with a power of 70 MVA.  

The 30 and 12 kV installations will then be modernised, with shielded cubicles also SF6 insulated. In addition, the overhead electricity lies merging at the substation will be re-ordered by compacting them and placing them partially underground. This, along with the reduction in space resulting from the refurbishment of the 132 kV installations, will significantly decrease the visual impact of the site, which will also benefit from the restructuring of the remaining spaces and their development as green areas. 

Once the substation has been refurbished, Viesgo will restructure the original Thermal Power Plant building that houses a turbo generator commissioned in 1915 and that is now a piece of historic-industrial heritage. This action is part of Viesgo’s commitment to preserve this heritage that forms part of the company’s history. 

The refurbishment will guarantee safe, efficient operations, providing the installation with the most modern electrical technology and notably improving the quality of electricity supply in Asturias.