From OpenStreetMap Wiki
Jump to navigation Jump to search
Public-images-osm logo.svg power = circuit
Arrangement of connected physical lines involved in the same power system Edit this description in the wiki page. Edit this description in the data item.
Group: Power
Used on these elements
should not be used on nodesshould not be used on waysshould not be used on areasmay be used on relations
Useful combination
Status: proposedPage for proposal

As described on many power grid operators' websites, power lines ways don't reflect the real power exchange path. Since OSM uses a relational model to link up path ways, it's possible to define a tagging model to design power circuits as relation between power lines ways on the map.

You may find a little description of how power circuits works on circuits=* page.

This page describes a proposed tagging that is waiting to be reviewed. This documentation was created because power=circuit relations begin to be well used and mappers may look for up to date explanations. Always refer to proposal.

Power routing in OSM

Here are the two main point of view which had been expressed on OSM so far. The first one is in favour of type=route + route=power to map circuits since the power exchange is not so different of public transportation networks. The second aim to totally distinguish power routes and transport routes and gives a brand new tagging model.

Tagging similar to transportation routes

This method of tagging should be deprecated. To save the history the description of this method is moved to the special page.

Tagging power circuits with a relation

Power line routes are not similar to transportation routes. Power lines have exactly two end point and have no "stops" in the middle. The beginning and the end (source and consumer of energy) of the line may exchange sometimes (e.g. in case of emergency switching). A power line may have T-shape connection to another one, but it is not an intermediate stop, it is a beginning of the other line. Also there are no travelling things like buses, passengers or travellers as in "common" routes. A travelling of electrons is rather physical abstraction, and it is not so simple as "small moving balls".

The relation for power circuits must be able, ideally, to tag splitting of phases to individual towers and gathering of them together; T-shaped circuits connections; supporting structures when part of wire does not transmit electricity but only acts as a holding device.

Among other issues, a special relation will help us not to confuse, when we make a map of transportation routes. Because a map of travelling routes and a map of power lines are different kinds of maps. In case of special relation for power lines a software will not have to analyse the values of route=* (is it equal to "power" or not?) but may rely on a type=power only.

So the structure of this relation is very different from structure of a route relation. That is why we should not tag power circuits with type=route + route=power. We should think about a special relation, and I suggest type=power + power=circuit for this purpose.



A relation of this type collects power line ways that constitute the same power circuit, with the same electrical characteristics, name, and reference mark.

Key Value Presence Comment
type power Mandatory Category of relations
power circuit Mandatory Power circuit routing
ref * Recommended Reference number, name, signature or another naming of the circuit
name *
short_name *
voltage * Recommended Electrical characteristics of the circuit
frequency *
cables *
wires *


Member's role Member's type Count Presence Member Description
line way one or more Recommended Power line An element of the power line
endpoint node way area relation 0, 1, 2 Recommended Terminal object A substation, a power tower, or another device where the circuit starts / ends


The following drawing illustrates a connection of the substation "H" with two other substations: "K" and "T".

At the substation "H" both of the circuits run on the same towers (line segment 1), then split (the segments 2 and 3). Then the phases of the circuit "H—T" split (4,5,6) and then gather together again (line 7).

Surly power transmission proposal.png

Tagging relations

Relation Relation's tags Relation's members, in the following order
relation First circuit's relation type=power
area polygon of the substation "H" (role endpoint);
way ways 1, 2 (role line);
area polygon of the substation "K" (role endpoint)
relation Second circuit's relation type=power
area polygon of the substation "H" (role endpoint);
way way 1, 3 (role line);
way ways 4, 5, 6 in any order (role line);
way way 7 (role line);
area polygon of the substation "T" (role endpoint)

Tagging ways and polygons:

Way area H area K area T way 1 way 2 way 3 way 4 way 5 way 6 way 7
Tags power=substation