How big is Portugal's transmission network?

OverWatts maps 5,975 km of transmission line in Portugal, across 1,628 segments, plus 55 substations. This is mapped length from OpenStreetMap, not an operator-reported total — where OSM is incomplete the figure is a floor, never a ceiling.

What voltage is Portugal's grid?

Most of the mapped network is extra-high voltage (380–764 kV): 3,210 km of 5,975 km. The highest voltage tagged anywhere in the country is 400 kV.

How complete is the grid map for Portugal?

Strong — 64 km of mapped line per 1,000 km² of land, ahead of 95% of the 153 countries with any mapped grid. Coverage grades how completely OpenStreetMap has drawn the network, not how much network exists; large, sparsely-populated countries score low for geographic reasons alone.

Who operates the grid in Portugal?

REN, Energias de Portugal, Iberdrola and 5 others are tagged as operators on mapped segments. Operator tags are present on 99% of Portugal's segments, so this ranks who is *recorded*, not market share.

What interconnectors connect Portugal to its neighbours?

2,700 MW of cross-border transfer capacity to Spain, plus 2,900 MW planned. Capacities are from the Global Transmission Database (v1.0, 2023).

Portugal · electricity network

Portugal power grid

OverWatts maps 5,975 km of Portugal's electricity transmission network across 1,628 line segments and 55 substations, the 48th most-mapped grid of 153 countries. Its backbone is extra-high voltage (380–764 kV), carrying 3,210 km — 54% of the mapped length, with the highest tagged voltage at 400 kV. That works out to 64 km per 1,000 km² of land — strong OpenStreetMap coverage, ahead of 95% of mapped countries. It is connected to 1 neighbouring grid by 2,700 MW of existing cross-border transfer capacity, with a further 2,900 MW planned.

Open the grid lens →Portugal profile →

5,975 km

Mapped transmission line

Substations

#48

of 153 mapped grids

2.7 GW

cross-border · 1 neighbours

400 kV

Highest voltage

OpenStreetMap coverage

Strong64 km / 1,000 km²ahead of 95% of 153 mapped countries

This grades how completely OpenStreetMap has drawn Portugal's network — not how much network exists. Large, sparsely-populated countries score low for geographic reasons alone, and every kilometre here is mapped length, so the totals are a floor rather than an operator-reported figure. 37% of segments carry a real line name and 99% an operator tag.

Mapped line length by voltage

380–764 kV3,210 km 54%
220–379 kV2,764 km 46%

1,628 segments · a segment is credited to the country containing its midpoint, so a border-crossing line counts once, on one side.

Cross-border links from Portugal

Spain2.7 GW
Spain1.9 GW · planned
Morocco1.0 GW · planned

2.7 GW existing · 2.9 GW planned · capacities from the Global Transmission Database v0.1 (CC BY 4.0), existing as of 2023

On the interactive map

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Load against the network

14.9 GW

Operating generation

109

km of line per substation

km per 1,000 km²

Where there is room to connect a new load depends on published hosting capacity, which most operators release only as their own map. OverWatts does not yet ingest those feeds, so these are the density measures the open data supports — generation and mapped demand against mapped network — not a headroom figure.

Operators tagged on Portugal's network

Segment counts from OSM `operator` tags, merged across spellings. Present on 99% of segments — this ranks who is recorded, not market share.

How Portugal compares · mapped grid by country

1. People's Republic of China624,300 km
46. New Zealand6,451 km
47. Myanmar6,159 km
48. Portugal5,975 km
49. Iraq5,765 km
50. Democratic Republic of the Congo5,746 km

Frequently asked

How big is Portugal's transmission network?: OverWatts maps 5,975 km of transmission line in Portugal, across 1,628 segments, plus 55 substations. This is mapped length from OpenStreetMap, not an operator-reported total — where OSM is incomplete the figure is a floor, never a ceiling.
What voltage is Portugal's grid?: Most of the mapped network is extra-high voltage (380–764 kV): 3,210 km of 5,975 km. The highest voltage tagged anywhere in the country is 400 kV.
How complete is the grid map for Portugal?: Strong — 64 km of mapped line per 1,000 km² of land, ahead of 95% of the 153 countries with any mapped grid. Coverage grades how completely OpenStreetMap has drawn the network, not how much network exists; large, sparsely-populated countries score low for geographic reasons alone.
Who operates the grid in Portugal?: REN, Energias de Portugal, Iberdrola and 5 others are tagged as operators on mapped segments. Operator tags are present on 99% of Portugal's segments, so this ranks who is *recorded*, not market share.
What interconnectors connect Portugal to its neighbours?: 2,700 MW of cross-border transfer capacity to Spain, plus 2,900 MW planned. Capacities are from the Global Transmission Database (v1.0, 2023).

Elsewhere in Portugal

Transmission lines Substations Power plants Data centres

Network geometry: OpenStreetMap (ODbL) © OpenStreetMap contributors, ingested and measured by OverWatts · derived 2026-07-26. Counts every mapped line of 220 kV and above; the map layer draws the ≥380 kV backbone only, so it shows less than is measured here.