GridInspector Methodology

About GridInspector

GridInspector displays the health score of OpenStreetMap (OSM) data for the electricity transmission network across countries worldwide.

This health score is based on two key indicators: Quality and Coverage.

The Quality indicator measures the consistency and accuracy of OSM data. For example: are the voltages correctly entered? Are the lines properly connected? Are the power towers correctly linked to the lines? The methods used to calculate these quality indicators are described below, and some are based on Osmose analysis.

The Coverage indicator compares the total circuit lengths in OSM with official national data, where available. The official data sources used are compiled on this page.

All algorithms used to calculate the indicators and generate the map are available in the following GitHub repositories: This tool was created by Dynartio as part of the MapYourGrid project.

Method for calculation of quality indicators

Line connectivity

A line is connected if it serves to link two substations. If it is connected on only one side, or not at all, it is not connected. Line connectivity is therefore the number of connected lines out of the total number.
  • nb_power_line_cable_connected = Number of connected power line or cable according OSM Power Grid Map Analysis.
  • nb_power_line_cable = Number of power line or cable according OSM Power Grid Map Analysis.
value(%) = 100 * nb_power_line_cable_connected / nb_power_line_cable

How to improve this score: Connect lines to substation or to appropriated line_management nodes.

Grid overall connectivity (without circuits)

Indicates whether the entire network of connected substations is connexe or not. The indicators reflects the number of substations connected in the different components of the graph. It is computed through OSM Power Grid Map Analysis. This indicator does not take circuit relations into account.

How to improve this score: Connect subparts of the national grid together with power lines.

Grid overall connectivity (with circuits)

Indicates whether the entire network of connected substations is connexe or not. The indicators reflects the number of substations connected in the different components of the graph. It is computed through OSM Power Grid Map Analysis. This indicator does take circuit relations into account.

How to improve this score: Connect subparts of the national grid together with power lines or power circuits.

"Cables"-tag completeness on lines

Indicates the proportion of power lines for which the "cables"-tag has been completed.
  • nb_osm_power_line_cable = Number of items that are tagged "power=line" or "power=cable" in OpenStreetMap.
  • nb_osm_power_line_cable_without_cables = Number of items that are tagged "power=line" or "power=cable" in OpenStreetMap and have no "cables"-tag.
value(%) = 100 * nb_osm_power_line_cable_without_cables / nb_osm_power_line_cable

How to improve this score: Complete "cables" tag on power lines.

"Circuits"-tag completeness on lines

Indicates the proportion of power lines for which the "circuits"-tag has been completed.
  • nb_osm_power_line_cable = Number of items that are tagged "power=line" or "power=cable" in OpenStreetMap.
  • nb_osm_power_line_cable_without_circuits = Number of items that are tagged "power=line" or "power=cable" in OpenStreetMap and have no "circuits"-tag.
value(%) = 100 * nb_osm_power_line_cable_without_circuits / nb_osm_power_line_cable

How to improve this score: Complete "circuits" tag on power lines.

"Voltage"-tag completeness on lines

Indicates the proportion of power line for which the "voltage"-tag has been completed.
  • nb_osm_power_substations = Number of items that are tagged "power=substation" in OpenStreetMap.
  • nb_osm_power_substations_without_voltage = Number of items that are tagged "power=substation" in OpenStreetMap and have no "voltage"-tag.
value(%) = 100 * nb_osm_power_substations_without_voltage / nb_osm_power_substations

How to improve this score: Complete "voltage" tag on power lines.

"Voltage"-tag completeness on substations

Indicates the proportion of power substations for which the "voltage"-tag has been completed.
  • nb_osm_power_substations = Number of items that are tagged "power=substation" in OpenStreetMap.
value(%) = 100 * nb(OSM power=substation & voltage!='')/ nb_osm_power_substations)

How to improve this score: Complete "voltage" tag on power substations.

Connected power tower

Indicates the proportion of power towers that are well connected to a power line or minor_line.
  • nb_oc1_t = number of Osmose-Class1 issues (i.e. Lone power tower or pole) where the concerned node is a power tower.
  • nb_osm_power_tower = Number of nodes that are tagged "power=tower" in OpenStreetMap.
value(%) = 100 * (1 - nb_oc1_t / nb_osm_power_tower)

How to improve this score: Connect power tower on power line. This is solving some of Osmose-Class1 issues (i.e. Lone power tower or pole).

Completed power lines

A power line is not completed if one of its ends is not an other line, a portal, or an appropriated line_management node.
  • nb_oc2 = number of Osmose-Class2 issues (i.e. Unfinished power transmission line)
  • nb_osm_power_line = Number of ways that are tagged "power=line" in OpenStreetMap.
value(%) = 100 * (1 - nb_oc2 / 2*nb_osm_power_line)

How to improve this score: Connect power line to an other line, to a portal, or to an appropriated line_management node. This is solving Osmose-Class2 issues (i.e. Unfinished power transmission line).

Line-to-line voltage consistency

Connected lines must have coherent voltage.
  • nb_oc3 = number of Osmose-Class3 issues (i.e. Connection between different voltages)
value(%) = 100 * (1 - nb_oc3 / nb(connection nodes) )

Connection nodes computed by grid analysis.

Warning: The Osmose-Class3 issue is refering to line connections AND to minor_line connections. It is not possible yet to distinguish line and minor_line in the issue. Thus the indicator is not really consistent yet regarding the transmission grid.

How to improve this score: Verify the consistency of line voltages on joining nodes. This is solving Osmose-Class3 issues (i.e. Connection between different voltages).

Line-to-substation voltage consistency

Line voltage should be corresponding to its linked substation voltage.
  • nb_oc7 = number of Osmose-Class7 issues (i.e. Unmatched voltage of line near of substation)
  • nb_line_substation_connection = number of tuple (substation ; connected line) computed by OSM Power Grid Map Analysis.
value(%) = 100 * (1 - (nb_oc7 / nb_line_substation_connection))

How to improve this score: Verify voltage between line and connected substation. This is solving Osmose-Class7 issues (i.e. Unmatched voltage of line near of substation).

Estimated spatial coverage of substations

Represents the proportion of the surface area of densely populated areas that is covered by a substation.
  • d = area of densely populated areas
  • c = area of densely populated areas not covered by substation (Hypothesis: coverage radius of a substation = 40 km)
value(%) = 100 * c / d

Population density source = https://data.humdata.org/dataset/kontur-population-dataset-3km