How big is Italy's transmission network?

OverWatts maps 18,500 km of transmission line in Italy, across 3,671 segments, plus 211 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 Italy's grid?

Most of the mapped network is extra-high voltage (380–764 kV): 10,100 km of 18,500 km. The highest voltage tagged anywhere in the country is 500 kV.

How complete is the grid map for Italy?

Strong — 58.9 km of mapped line per 1,000 km² of land, ahead of 92% 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 Italy?

Terna S.p.A., Terna, swissgrid and 5 others are tagged as operators on mapped segments. Operator tags are present on 6% of Italy's segments, so this ranks who is *recorded*, not market share.

What interconnectors connect Italy to its neighbours?

9,220 MW of cross-border transfer capacity to Switzerland, France, Slovenia, Montenegro, Greece, Austria, Malta, plus 8,390 MW planned. Capacities are from the Global Transmission Database (v1.0, 2023).

Italy · electricity network

Italy power grid

OverWatts maps 18,500 km of Italy's electricity transmission network across 3,671 line segments and 211 substations, the 21st most-mapped grid of 153 countries. Its backbone is extra-high voltage (380–764 kV), carrying 10,100 km — 54% of the mapped length, with the highest tagged voltage at 500 kV. That works out to 58.9 km per 1,000 km² of land — strong OpenStreetMap coverage, ahead of 92% of mapped countries. It is connected to 7 neighbouring grids by 9,220 MW of existing cross-border transfer capacity, with a further 8,390 MW planned.

Open the grid lens →Italy profile →

18,500 km

Mapped transmission line

211

Substations

#21

of 153 mapped grids

9.2 GW

cross-border · 7 neighbours

500 kV

Highest voltage

OpenStreetMap coverage

Strong58.9 km / 1,000 km²ahead of 92% of 153 mapped countries

This grades how completely OpenStreetMap has drawn Italy'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. 24% of segments carry a real line name and 6% an operator tag.

Mapped line length by voltage

380–764 kV10,100 km 54%
220–379 kV8,312 km 45%
<220 kV105 km 1%
Voltage untagged32 km 0%

3,671 segments · a segment is credited to the country containing its midpoint, so a border-crossing line counts once, on one side.

9.2 GW existing · 8.4 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

61.7 GW

Operating generation

Data centres mapped

km of line per substation

58.9

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 Italy's network

Segment counts from OSM `operator` tags, merged across spellings. Present on 6% of segments — this ranks who is recorded, not market share.

How Italy compares · mapped grid by country

1. People's Republic of China624,300 km
19. Vietnam18,900 km
20. Japan18,800 km
21. Italy18,500 km
22. Germany17,000 km
23. Egypt15,500 km

Frequently asked

How big is Italy's transmission network?: OverWatts maps 18,500 km of transmission line in Italy, across 3,671 segments, plus 211 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 Italy's grid?: Most of the mapped network is extra-high voltage (380–764 kV): 10,100 km of 18,500 km. The highest voltage tagged anywhere in the country is 500 kV.
How complete is the grid map for Italy?: Strong — 58.9 km of mapped line per 1,000 km² of land, ahead of 92% 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 Italy?: Terna S.p.A., Terna, swissgrid and 5 others are tagged as operators on mapped segments. Operator tags are present on 6% of Italy's segments, so this ranks who is *recorded*, not market share.
What interconnectors connect Italy to its neighbours?: 9,220 MW of cross-border transfer capacity to Switzerland, France, Slovenia, Montenegro, Greece, Austria, Malta, plus 8,390 MW planned. Capacities are from the Global Transmission Database (v1.0, 2023).

Elsewhere in Italy

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.