Projects concluded in 2013

In 2013, the projects concluded in the National Electricity Transmission Network
(RNT) contributed toward improved reception capacity, particularly from
renewable sources, toward improved international exchange capacities with
Spain and to better power feeding conditions to distribution networks, and
towards the safety and reliability of the overall system operation.

In the Trás-os-Montes region, to reinforce supply to consumers and improve
power feeding conditions to the network in that area, a new connection came
into operation between the Valpaços and Vila Pouca de Aguiar substations,
completing the 220 kV circuit of the mountainous axis between Lagoaça
and Valdigem.

On the of the Douro axis and in the Porto area, of note are the 400kV
connections between Armamar-Recarei and Recarei-Vermoim, along with the
introduction of a 400kV level at Vermoim substation, reinforcing the safety and
reliability of supply to consumers in the Greater Porto region and improving
interconnection capacity. Also in the Porto area, the refurbishment to 220kV
of the Maia steel plant was concluded and came into operation, along with the
connection that feeds it.

In the southern coastal region of Greater Porto a new 400/60kV substation came
online at Feira, supplying consumers in the municipalities of São João da Madeira,
Feira and Arouca.

In Beira Interior a second 150kV connection came into service between the
Falagueira and Castelo Branco substations, providing this interior region with improved supply  of renewable energies and enhanced overall safety of the network operation.

In the Lisbon area, in order to reinforce supply to consumers, it is worth noting
the construction of a new 220kV underground circuit between the Alto de Mira
and Sete Rios substations. Also with the aim of reinforcing supply to consumers,
the introduction of a 400kV level at the Fernão Ferro substation was concluded.
Seven new transformers started operation, with a total power increase of 1 069
MVA (of which 320MVA is at the Maia steel plant substation).

Main investments underway

Reinforcement of the interconnection capacity between Portugal and Spain

  • I n order to reinforce the exchange capacities between Portugal and Spain, a new 400 kV interconnection is planned in the Minho region, connecting the future Viana do Castelo installation on the Portuguese side with Fontefria on the Spanish side

Connection of special status producers to the RNT
(except for large scale hydropower)

  • Transformation improvements in various substations

Connection of large-scale producers to the RNT

  • Entry into service of a new 400kV switching station in Vieira do Minho and the implementation of two connections, also at 400kV, between this point and the Pedralva substation, to connect the power upgrades from the Venda Nova (Venda Nova III ) and Salamonde (Salamonde II ) hydroelectric plants;
  • Construction of a new 400kV axis between the Porto region and the area of Viana do Castelo, running east to the Pedralva substation. This axis, as well as proving important in ensuring the running of the large amounts of new hydropower plants in the Cávado/Alto Minho, will also form an integral part of the new interconnection with Spain in that region, thereby facilitating international exchanges. At the same time, the new RNT substation at Vila Nova de Famalicão which forms part of this axis, will provide improved safety in the power supply to those consumers in the coastal Minho region;
  • In the Central region, in order to connect the new hydroelectric plant at Girabolhos, the construction of a new 400kV line is planned between the Penela substation and the Seia area.

Feeding to the distribution networks to improve the supply of large load centres

  • I n Minho, opening of a 150/60 kV substation in the Fafe area, which also supplies the neighbouring counties of Guimarães, Vizela and Felgueiras
  • I n Lisbon, the opening of the 220/60 kV Alto de S. João substation, fed by two underground circuits, from Sacavém and Fanhões (Prior Velho)
  • I n the Setúbal Peninsula, the completion of the second 150 kV overhead line between the substations of Fernão Ferro and Trafaria
  • I n the Alentejo, construction of a new 400 kV line between Estremoz and Divor