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Public-images-osm logo.svg power = line
High-voltage power lines used for power transmission, usually supported by towers or pylons Show/edit corresponding data item.
Rendering in OSM Carto
Power line.png
Group: power
Used on these elements
should not be used on nodesmay be used on waysshould not be used on areasshould not be used on relations (except multipolygon relations)
Useful combination
See also
Status: de facto

The tag power=line is used to map high-voltage overhead power lines (IEC 466-01-02) used for power transmission (IEC 466-01-13), usually supported by towers or pylons power=tower.

For less massive lines (mainly part of the distribution system, from mains voltage to about 45 kV, depending on the country or area), usually carried on poles, use power=minor_line.
For underground or underwater power cables use power=cable.

How to map

Draw one way way for all circuits connected to one power tower and add the power=line to it. All lines forming the transmission system are one power=line. It is not necessary to tag power lines with a layer=* unless two lines cross over each other.

If the lines connect mid air at a crossing point without any ground support then use power=connection on the node connecting them.

Key Value Comment Recommendation
power line It's a power line, normally mapped as a way. Mandatory
voltage <operating voltage> The voltage at which the line is operated. May be semicolon-separated if there are multiple voltages. Recommended
cables <number of conductors> The number of different phase conductors for this power line. Usually multiples of 3 (6, 9, 12) Recommended
circuits <number of circuits> The number of separate electrical circuits carried by this power line. For the common 3-phase systems, it's no. of conductors/3 Recommended if not implicit
<line operator> The name of the company which operates this power line Recommended
<line owner> The name of the organisation that owns this power line Optional
wires <wire bundle per conductor> The bundle form factor for each conductor of the power line Optional
frequency <operating frequency> The frequency in hertz at which the power line is operating. May be semicolon-separated if there are multiple frequencies. Optional
name <name> The name of this power line Optional
ref <reference> The reference of this power line Optional
line bay, busbar or substation Specifies that a line is a busbar or bay in a substation Optional

Line supports

The towers that support the power line can be mapped using nodepower=tower and poles with nodepower=pole and you may find extensive information on each pages.

It is possible to connect power lines to power=portal inside power=substation using power=insulator on the connecting node. power=terminal is also used at the connection with buildings without a dedicated power tower or portal to support the end of the line.

The choice between towers and poles not only depends on the importance of the line but on the surrounding environnement as well. As transmission lines are usually massive, towers are preferred to support them and it also possible to find poles at appropriate locations. You are encouraged to check the shape of support: lattice or solid metal pieces assemblies for towers and single wooden or concrete parts for poles.

Since power lines conductors are high voltage and usually uninsulated, they can only be located overhead to protect them from grounding with external elements and actually insulated with air.

Additional tags

It is also possible to give some additional and advanced information about power lines:

  • The number of wires=* per conductor.
  • You may use cables=* for the number of power-carrying conductors (bundles of wires) the line is composed of.
  • circuits=* corresponds to the number of electrical circuits (logical bundles of conductors). The tag may be used when the number of power-carrying conductors is unknown (often the case for underground cable connections) or when the number of circuits is different from cables=* divided by 3 (or by the number of phases of the line).

Lines carrying multiple voltages or frequencies

If a line has multiple circuits at different voltages, they should be listed individually, separated by semicolons. For example, if there are two circuits at 66 kV and one at 33 kV, the line should be tagged as:

If there are also multiple frequencies (only in the case of HVDC or traction power), the frequency=* tag should also be semicolon separated. In this case, the frequency=* tag should have the same number of semicolon-separated items as the voltage=* tag. For example, for a line carrying 220 kV and 110 kV at 50 Hz, as well as 110 kV at 16.7 Hz for traction power:

If a power line is technically designed for another voltage than it's operated, it was suggested that this may be tagged with construction:voltage=*, however this conflicts with the meaning of construction:*=*.

See also the discussion at power routing proposal.


Picture/description Tags OSM Carto Openinframap
Electricity pylon and power lines
A typical illustration of a power line: high voltage conductors supported by towers/pylons
High voltage power lines are usually mounted on towers, but may be supported by poles in certain regions, such as this power line in Canada. Such should not be tagged power=minor_line

Three conductors correspond to one circuit (except traction power lines and high voltage direct current/HVDC). Every circuit has one voltage=* level on which it operate.


In addition to rendering on power lines on OSM Carto the following services are also available:

See also