REN - Redes Energéticas Nacionais has completed the first stage of the expansion of Vermoim substation, located in Maia municipality, to 400 kV. This investment totals about EUR 20 million. This project, which is included in the Electricity Transmission Grid Investment Plan, has created an alternative 400 kV node to Recarei substation, located in Paredes municipality, thereby improving the reliability of the network in this zone of the country. This is the first time in Portugal that a 400 kV substation has deployed compact technology to be erected inside a building, which has minimized the impact of the facility on the surrounding urban environment. The first phase, which is now operational, contains the circuit-breaking, switching and measuring equipment needed to connect two 400 kV power lines as well as a new 400/220 kV 450 MVA autotransformer and two new 400/60 kV 170MVA transformers. The second 400 kV line will be brought into service later this year. The project took particular care to reduce the environmental impact. This included installing encapsulated transformers to reduce environmental noise and making use of existing lines already built for these voltages but which were operating at lower voltages. According to João Conceição, Executive Director of REN, this project, which began in 2011 and terminates at the end of 2014, 'aims to strengthen the region's transmission capability, power quality and supply security.'