How big is China's transmission network?

OverWatts maps 624,300 km of transmission line in China, across 76,118 segments, plus 602 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 China's grid?

Most of the mapped network is high voltage (220–379 kV): 359,300 km of 624,300 km. The highest voltage tagged anywhere in the country is 1,150 kV.

How complete is the grid map for China?

Strong — 66.4 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 China?

China Southern Powergrid, 2, 中華電力有限公司 CLP Power Hong Kong Limited are tagged as operators on mapped segments. Operator tags are present on 0% of China's segments, so this ranks who is *recorded*, not market share.

What interconnectors connect China to its neighbours?

2,418 MW of cross-border transfer capacity to Russia, Vietnam, Mongolia, Myanmar, Laos, North Korea, plus 1,000 MW planned. Capacities are from the Global Transmission Database (v1.0, 2023).

China · electricity network

China power grid

OverWatts maps 624,300 km of China's electricity transmission network across 76,118 line segments and 602 substations, the 1st most-mapped grid of 153 countries. Its backbone is high voltage (220–379 kV), carrying 359,300 km — 58% of the mapped length, with the highest tagged voltage at 1,150 kV. That works out to 66.4 km per 1,000 km² of land — strong OpenStreetMap coverage, ahead of 95% of mapped countries. It is connected to 6 neighbouring grids by 2,418 MW of existing cross-border transfer capacity, with a further 1,000 MW planned.

Open the grid lens →China profile →

624,300 km

Mapped transmission line

602

Substations

of 153 mapped grids

2.4 GW

cross-border · 6 neighbours

1,150 kV

Highest voltage

OpenStreetMap coverage

Strong66.4 km / 1,000 km²ahead of 95% of 153 mapped countries

This grades how completely OpenStreetMap has drawn China'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. 1% of segments carry a real line name and 0% an operator tag.

Mapped line length by voltage

≥765 kV46,400 km 7%
380–764 kV216,100 km 35%
220–379 kV359,300 km 58%
<220 kV194 km 0%
Voltage untagged2,415 km 0%

76,118 segments · a segment is credited to the country containing its midpoint, so a border-crossing line counts once, on one side.

2.4 GW existing · 1.0 GW planned · capacities from the Global Transmission Database v0.1 (CC BY 4.0), existing as of 2023

On the interactive map

Open the interactive map →

Load against the network

2679 GW

Operating generation

Data centres mapped

1037

km of line per substation

66.4

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 China's network

China Southern Powergrid22 88%
22 8%
中華電力有限公司 CLP Power Hong Kong Limited1 4%

Segment counts from OSM `operator` tags, merged across spellings. Present on 0% of segments — this ranks who is recorded, not market share.

How China compares · mapped grid by country

1. People's Republic of China624,300 km
2. India271,000 km
3. United States of America239,100 km

Frequently asked

How big is China's transmission network?: OverWatts maps 624,300 km of transmission line in China, across 76,118 segments, plus 602 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 China's grid?: Most of the mapped network is high voltage (220–379 kV): 359,300 km of 624,300 km. The highest voltage tagged anywhere in the country is 1,150 kV.
How complete is the grid map for China?: Strong — 66.4 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 China?: China Southern Powergrid, 2, 中華電力有限公司 CLP Power Hong Kong Limited are tagged as operators on mapped segments. Operator tags are present on 0% of China's segments, so this ranks who is *recorded*, not market share.
What interconnectors connect China to its neighbours?: 2,418 MW of cross-border transfer capacity to Russia, Vietnam, Mongolia, Myanmar, Laos, North Korea, plus 1,000 MW planned. Capacities are from the Global Transmission Database (v1.0, 2023).

Elsewhere in China

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.