Power networks/Portugal

High-voltage power lines in Open Infrastructure Map.

This page describes the electrical power network of Portugal (Q45), including the archipelagos of the Azores (Q25263) and Madeira (Q26253). It also provides guidance on how to map the network accurately in OSM.

The information presented here applies specifically to the mainland Portuguese transmission and distribution grid. While the power systems of the Azores and Madeira differ in certain structural and operational aspects, they follow the same fundamental principles. It should be noted that the two archipelagos operate independent power networks, managed by separate entities, and are not electrically interconnected with continental Portugal.

Organization

The electricity system in continental Portugal is managed in a single-operator/monopoly regime, as a result of forcible nationalizations and mergers in the period of 1974-1976. Until 1994, the only power network operator, also operating the majority of power production capacity, was EDP, in a vertically integrated monopoly. The most relevant change since was that the ownership and operation of the transmission grid was first placed under REN with complete ownership of EDP, with REN leaving the sphere of influence of EDP after being privatized in 2000.

Operators

In Continental Portugal, the larger operators are:

• REN (Q1862842), very-high voltage (150-400kV) transmission grid.
• EDP (Q1341222), high voltage (60kV) sub-transmission grid, medium voltage (10-30kV) distribution grid, and the majority of low voltage (400V triphasic, 230V monophasic) distribution grid.

Some parts of the low voltage distribution grid and medium/low voltage substations are managed by smaller operators, most of which are cooperative companies (co-owned by retail customers), or public companies owned by smaller administrative divisions. These operators typically operate within a single municipality (município) or civil parish (freguesia).

• A Celer - Cooperativa Eletrificação de Rebordosa, C.R.L.
• A Eléctrica de Moreira de Cónegos, C.R.L.
• Casa do Povo de Valongo do Vouga
• CEL - Cooperativa Eléctrica do Loureiro, C.R.L.
• CEVE - Cooperativa Eléctrica de Vale D’Este, C.R.L.
• Cooperativa Eléctrica de Vilarinho, C.R.L.
• CESSN - Cooperativa Eléctrica S. Simão de Novais, C.R.L.
• Cooperativa de Eletrificação A Lord, C.R.L.
• Cooproriz - Cooperativa de Abastecimento de Energia Eléctrica, C.R.
• Junta de Freguesia de Cortes do Meio

In the Azores and Madeira, there is no true very-high voltage transmission grid, owed to the small size of the archipelagos that doesn't require long-distance electricity transmission.

In the Azores, the high voltage (30-60kV) transmission grid, the medium voltage (10-30kV, with a small part at 6kV) distribution grid, and the low voltage (400V) distribution grid, are operated by EDA (Q131463417). Every island has an isolated power grid system, so EDA assigns different roles (transmission vs. distribution) to the same voltage levels depending on the specific needs of each island.

In Madeira, the high voltage (30-60kV) transmission, the medium voltage (6.6kV) distribution grid, and the low voltage (400V) distribution grid, are operated by EEM (Q138337537). The two islands with electricity (Madeira and Porto Santo) have isolated power grids. In Madeira, the 30kV voltage level is mostly used in transmission, although 2.6% of medium/low voltage substations are fed at 30kV.

State of the map

As of 2026-02-18, the state of the mapped power grid in Portugal is as follows:

• Very-high voltage power lines (REN, 150-400kV) are all mapped, and are updated as needed based on users' information about new line construction, and cross-checked every year against the operator-published Electric Network Description report.
• High voltage power lines (E-REDES, 60kV) are all mapped within the limits of what's possible and reasonable, based on users' information about new line construction, and cross-checked every year against the operator-published Electric Network Description report. The reports published by E-REDES have a lower standard of quality than those published by REN, so some of the lines listed in their reports are no longer operating.
• Medium voltage power lines (E-REDES, 10-30kV) mapping coverage varies a lot by region, here is a summary of mapping coverage estimates per district:
  • Faro: 100%
  • Beja: 100%
  • Évora: 100%
  • Portalegre: 100%
  • Castelo Branco: 100%
  • Guarda: 100%
  • Lisboa: 100%
  • Santarém: 100%
  • Viana do Castelo: 90%
  • Braga: 75%
  • Leiria: 66%
  • Aveiro: 66%
  • Porto: 50%
  • Coimbra: 33%
  • Bragança: 33%
  • Vila Real: 25%
  • Viseu: 25%

State of the map in Continental Portugal

Power transmission network in Portugal (150-400kV), operated by REN.

Power subtransmission network in Portugal (60kV), operated by E-REDES.

Power distribution network in Portugal (10-30kV), operated by E-REDES.

State of the map in the Azores and Madeira

Power network in the Azores, operated by EDA.

Power network in Madeira, operated by EEM.

Even districts with 100% mapping are liable to have some minor power lines not mapped yet.

Network description

Voltages and frequency

Frequency : 50 Hz

Network	Voltage	Comments	Appearance
Transmission	400 kV	Very high voltage power lines, part of the National Transport Network. Operated by REN.
	220 kV
	150 kV
	130 kV	This voltage is only used by historical very high voltage power lines that start in Lindoso Hydroelectric Power Plant, one of the oldest large-scale power plants. It is only used in two power lines, Lindoso - Conchas (interconnection with Spain) and Lindoso - Pedralva, with the Pedralva substation having a unique 130/150kV transformer to transform power into 150kV, which is one of the standard very high voltages used in Portugal.
Distribution	60 kV	High voltage power lines, part of the National Distribution Network. Operated by E-REDES. These power lines do not serve customers directly; they may sometimes serve large-scale customers that need to draw or inject large amounts of power into the network. Aside from that, they're mostly used by E-REDES to balance loads between its high/medium voltage substations without using REN's very high voltage network, and power lines are point-to-point, so it can be described as a subtransmission network.	Aerial: power lines, in groups of 3 cables, with very rare branching. It is fairly common for high voltage power lines to have 1 or 2 circuits. Power towers: may either be concrete towers, or steel lattice towers. These power towers are commonly numbered sequentially (although sometimes power line supports may be numbered like 82, 83, 83A, 83B, 84, etc.) and also have the line reference inscribed in them (when a power tower supports two circuits, the two circuits' references are inscribed in different sides of the same support); the concrete poles have the numbers and line reference painted at eye-level, while steel lattice poles have a small steel plate attached above eye-level, typically together with a yellow triangular "risk of death" signal. Distribution substations (high/medium voltage): High/medium voltage transformers: most are outdoors, sometimes separated from each other by concrete walls about 2m tall. High-voltage power lines connect to these transformers through aerial power lines. the medium voltage terminals of high/medium voltage transformers are briefly overground, but almost immediately transition to underground; it is common for the medium voltage terminal of this type of transformer to be connected to a tiny medium voltage busbar (where there's a single medium voltage overground busbar for each transformer), but it also typically transitions to underground after that.
	30 kV	Medium voltage power lines, part of the National Distribution Network. Operated by E-REDES. These power lines connect directly to small industries, or to minor substations.	Aerial: power lines, in groups of 3 cables, with often branching. Most medium voltage power lines only have one circuit, but occasionally power poles may support two circuits, one on each side of the pole. Power poles: may either be concrete poles with the shape of an H when seen vertically, or steel lattice poles. It is common for medium voltage power lines to transition from aerial to underground. Many of these poles are numbered sequentially with numbers painted at eye-level, typically up to 200 at most, and very rarely may also have the name of the medium voltage power line that the pole supports. Some poles have mechanical power switches, usually identified by a steel rod/mechanism running through the vertical extent of the pole, and a black rectangle painted in the pole at about eye-level with white letters; most switches are manually activated (usually start with "SEC" if they're a disconnector - seccionador and can only isolate non-energized circuits, or "INT SEC" if they're an load-break switch - interruptor/seccionador and can interrupt an energized circuit with nominal current values). Some switches may be remotely activated (always start with "OCR" because it's a remote switch - órgão de corte de rede), for these switches you can see a large white box containing the switching equipment on top of the pole, and sometimes see a radio antenna attached to the side of the pole. Distribution substations (high/medium voltage): most medium voltage power lines connect to distribution substations through poles with transition to underground. Most medium voltage power lines inside distribution substations are underground. In most distribution substations, medium-voltage switching equipment, busbars and auxiliary medium/low voltage transformers are located indoors. Some older substations may have the medium voltage power lines connected to portals, but these power lines typically transition to underground after connecting to the portal. Minor substations (medium/low voltage): there are two main types of medium/low voltage minor distribution substations. Transformer towers, typically in rural settings or where the power grid is older. About 95% of the time, transformer towers are directly connected to medium voltage power lines with anchor attachments (although very rarely they can also be attached with pins); the other 5% of the time, transformer towers are served by underground power lines (you may sometimes find nearby a medium voltage power line pole that transitions underground). Service buildings, typically in urban settings and modern (1975 and later) urban developments. You will often find nearby a medium voltage power line pole that transitions underground.
	15 kV
	10 kV
	6 kV	Legacy medium voltage power lines, only existing in the cities of Portalegre and Castelo Branco. Operated by E-REDES, they are part of the National Distribution Network. Efforts are being undertaken to convert these power lines into 30 kV, to match the voltages used by E-REDES in more recent lines set up in low-population areas around these two cities.	90% of the 6kV distribution network is underground, since this voltage level is only used in the urban areas of the cities of Portalegre and Castelo Branco.
	400 V	Low voltage power lines/cables, part of the National Distribution Network. Operated for the most part by E-REDES, although there are 10 other, municipality-level low voltage network operators as listed by ERSE, most of which are cooperative/municipal companies that historically predate E-REDES and its old equivalent EDP.	Aerial: typically copper cables insulated with plastic, supported by wooden poles with anchor attachments or street lights. Very rarely, and only in rural areas, they may appear as non-insulated power lines in groups of 3, vertically aligned, supported by wooden poles with pin attachments. Underground: most of the low-voltage power grid is made of underground cables in towns and cities. Distribution: made mostly through street cabinets, that do not house transformers.

These values are used for quality control in some OSM tools. If you change them, please also report it by creating an issue on GitHub. More information about country voltage QA.

There are other frequently used voltages, such as:

• 25kV, in most of the train traction system.
• 1.5kV DC, in the train traction system of the Cascais railway line.
• 30kV, very common in internal power lines/cables of wind farms in Continental Portugal.
• It is very common for power generators to generate power at non-standard voltages, usually in the range of 1-20kV, which are then stepped up by step-up/generator transformers before connecting to the distribution or transmission networks.

Operators

Operator	Network	Wikidata	Website	Wikipedia	Operating area	Information	Label	Taginfo
TODO	{{{network}}}	Q99999 WhatLinksHere	TODO	TODO			operator=TODO operator:wikidata=Q99999	operator=TODO

Interconnections

Neighbour country	Structure name	Technology	Voltage	Local end	Foreign end	OSM circuit	Notes
Spain	Alcáçova - Riocaya	50Hz AC	60kV	Alcáçova Alcáçova	Riocaya Riocaya	Alcáçova - Riocaya Alcáçova - Riocaya	On the Portuguese side, this interconnection is operated at the nominal voltage of 60kV, but on the Spanish side it sometimes appears with the nominal voltage of 66kV. It was decided to tag the circuit as 60kV, as the Portuguese side always uses 60kV nominal voltage, and in the case of Spain most documents mention 66kV but some also mention 60kV (example: ).

Neighbour country	Structure name	Year of commissioning	Technology	Voltage	Local end	Foreign end	OSM circuit	Notes
TODO								xxx

Planned projects

• ...

Data Sources

Source	License	Date	Suitable for OSM	Notes
Available Hosting Capacity in the National Distribution Grid	?	?	?	-

Network statistics

Portugal has 1444 power plants totalling 27,443 MW and 52,111 km of power lines mapped on OpenStreetMap (from OpenInfraMap, last update 2025-09-13)

Power line

From OpenInfraMap, last update 2025-09-13

Power Lines Voltage	Length
< 10 kV	24 km
10 kV - 25 kV	18,010 km
25 kV - 52 kV	16,002 km
52 kV - 132 kV	9,447 km
132 kV - 220 kV	2,010 km
220 kV - 330 kV	2,915 km
330 kV - 550 kV	2,904 km
> 550 kV	0 km
No voltage tagged	796 km
Total	52,111 km

Mapping process and community

Mapping success stories

TODO : Success stories are designed to highlight important contributions. Have you significantly improved the cartography of a country (added a new line, a power station, etc.)? Don't be shy, let us know below.

• Example : NAME [DATE YYYY-MM-DD]: My success stories in words.

Encountered problems and places to improve

• ....

Use of mapping strategies

TODO : Mapping strategies refer to Power networks/Guidelines#Mapping strategies. They are used for a methodical improvement of the OSM database. Once you have fully applied a strategy in this country, you should add or update your name, the date, the strategy, and a comment below. This way, other users can see whether it is worthwhile to carry out further investigations.

• Example : Search for "Unfinished major power lines" - last time applied by XXX [2025-MM-DD]
• .... - last time applied by XXX [2025-MM-DD]