Power generation refinement
Status:	Rejected (inactive)
Proposed by:	Don-vip
Tagging:	power=> power=plant, plant:output=*, power=generator, generator:type=*, power=substation, substation=*
Applies to:
Definition:	Clarify the current usage of the power=* key in energy generation context and introduce new tags for power plants, generators and substations.
Rendered as:	Identical to power=generator and power=sub_station
Draft start:	2011-06-03
RFC start:	2012-04-09
Vote start:	2012-04-27
Vote end:	2012-05-18

Contents 1 Proposal 2 Rationale 2.1 Wikipedia and IEC definitions 2.2 OSM usage 2.3 New approach 3 Tagging 3.1 Conventional power plant 3.1.1 Simple tagging 3.1.2 Advanced tagging 3.2 Wind farm 3.2.1 Simple tagging 3.2.2 Advanced tagging 3.3 Specific roles 3.4 Generator 3.5 Substation 3.6 Transformer 3.7 Deprecated tags 3.8 Life cycle management 3.8.1 Power features under construction 3.8.2 Decommissioned power facilities 3.8.3 Undergrounded power lines 4 Examples 4.1 Single-site facitilies 4.1.1 Fukushima 4.1.2 Olkiluoto 4.1.3 Thémis 4.1.4 Parker Ranch 4.2 Dispersed facilities 4.2.1 Middelgrunden 4.2.2 Hoover Dam 5 Features/Pages affected 6 Tools/Renderers affected 6.1 JOSM 6.2 Potlatch 2 6.3 Mapnik 6.4 ITO Map 7 See also 8 Comments 8.1 Voting

Proposal

This proposal aims to clarify the current usage of the power=* key in energy generation context, introduces a new tag: power=plant, a new namespace: plant:output=*, two new keys: generator:type=* and substation=*, fixes the spelling of power=sub_station to power=substation, and deprecates power=station.

Rationale

Wikipedia and IEC definitions

Wikipedia and IEC describe the power generation concepts in these terms:

• A power station (601-03-01, also referred to as a generating station, power plant, or powerhouse) is an industrial facility for the generation of energy (electricity, useful heat...).
• A substation (601-03-02) is a part of an electrical generation, transmission, and distribution system.
• A generator (151-13-35) is a device that converts one form of energy to another (example: mechanical energy or sun light to electricity).
• A wind farm (415-01-03) is a group of wind turbines in the same location used for production of electricity. The land between the turbines may be used for agricultural or other purposes. A wind farm may also be located offshore.

OSM usage

The easy way to map these features in OSM would have been to keep these terms with the same definition.

Instead, the current OSM usage is the following:

• power=generator is used to map power stations (for nuclear, thermal and hydro stations), but also generators (for wind turbines).
• power=station and power=sub_station are both used to map substations. It is said to avoid using power=station for power stations or substations, but this tag is not deprecated, even if disputed on talk pages.
• Nothing exists to map generators if power=generator is used for the power station. Some users create new power=generator nodes inside the main power=generator area.
• Nothing exists to map power stations if power=generator is used for power generators. Some users create another surrounding power=generator area around the generators, especially for nuclear power plants. A landuse=industrial could be used, but this tag is not enough to define a power station.
• Wind farms are usually not mapped. When they are, a surrounding power=generator area is created around its wind turbines, as for conventional power stations. This is not adequate, as the perimeter does not strictly exist (there is no fence around a wind farm), and the implied industrial nature of power=generator is not applicable to wind farms: the land between the turbines may be used for other purposes, especially agriculture (landuse=farm).

New approach

To have an unambiguous and consistent power generation scheme, it is proposed to:

• Create a new power=plant tag for what Wikipedia calls a power station. A nuclear power station with multiple reactors on one site with a single name (such as Fukushima II) would be contained within a single area outlining the whole facility tagged power=plant. An array of wind turbines known operated together and known by a single name might be represented by a node at some suitable location central to the array tagged power=plant.
• Create a new plant:output=* namespace for the rated output of the facility (which may not be a simple sum of their capacities). Its tagging being exactly the same as generator:output=*.
• Modify the current definition of power=generator to refer only to an individual power generation device rather than the entire power plant. Each turbine in a wind farm would be a node generator; each individual reactor within a larger nuclear power station would be a node or an area. The output of a generator would be the rated output for that particular device.
• Create a new generator:type=* key to distinguish generator types among a single generator:method=*. This is particularly needed for nuclear energy, where no electricity-producing fusion reactor is expected before 2033 (DEMO). All current nuclear reactors use fission. Fission reactors are classified by their design, and power plants can mix different generator types. For example, the French nuclear power plant of Flamanville contain two PWR and one EPR. reactor_type=* is already in use, but only in Chernobyl power plant.
• Fix the spelling of power=sub_station to power=substation. Indeed, a "sub station" would literally be a station for submarines, and not an electrical facility.
• Create a new substation=* key to distinguish substations by their nature, and not their size.
• Deprecate the controversial power=station tag. This tag has been created for "small substations", but we can distinguish substations by their voltage=* and substation=* instead.
• Clarify the usage of power=transformer

Tagging

Conventional power plant

A power plant is a facility where energy (electricity, useful heat...) is generated.

Simple tagging

A power=plant is tagged as a around the power plant perimeter (usually bordered by fence). This is the simplest tagging, recommended for beginner users, who are not familiar with relations. Experimented users should give a look to the advanced tagging (next chapter). In simple tagging, the power plant is tagged with the following attributes:

Key	Value	Comment	Recommendation
power	plant	Defines this area as a power plant.	mandatory
name	Individual name	The name by which the power plant is known.	recommended
operator	Operator	Name of the company that operates the power plant.	recommended
start_date	Date (YYYY-MM-DD)	Date when the construction was finished, using ISO 8601.	recommended
landuse	industrial	Apart of wind farms, a power plant is an industrial facility.	recommended if not already inside a bigger landuse=industrial, else optional
plant:output:*	Rated output of the facility	The rated output of the whole facility. The tagging is consistent with generator:output=*: a cogeneration plant would have for example plant:output:electricity=* and plant:output:hot_water=* keys.	recommended when using simple tagging

Advanced tagging

A power=plant can also be tagged as a using type=site. This advanced tagging is optional, it is allowed to ensure consistency with wind farms, and ease the computing of total power plant rating, by adding all the generator:output:* values of its generator members.

Key	Value	Comment	Recommendation
type	site	Defines this relation as a site.	mandatory
power	plant	Defines this site as a power plant.	mandatory
name	Individual name	The name by which the power plant is known.	recommended
operator	Operator	Name of the company that operates the power plant.	recommended
start_date	Date (YYYY-MM-DD)	Date when the construction was finished, using ISO 8601.	recommended
plant:output:*	Rated output of the facility	The rated output of the whole facility. The tagging is consistent with generator:output=*: a cogeneration plant would have for example plant:output:electricity=* and plant:output:hot_water=* keys.	recommended if the rated output is not a simple sum of its generators capacities.

Members of this relation are:

Way or Node	Role	Recurrence?	Refers to	Recommendation
	perimeter	1	Area or multipolygon defining the perimeter of the power plant (may be a landuse=industrial).	mandatory
	generator	1 or more	All power generators of the power plant.	mandatory
	substation	0 or more	All substations of the power plant.	recommended

Wind farm

A wind farm is a group of wind turbines in the same location used for production of electricity. 
The land between the turbines may be used for agricultural or other purposes.
A wind farm may also be located offshore.

Simple tagging

The simplest way to tag a wind farm is to create a using power=plant approximatively in the centre of its array of wind turbines. The attributes are the same as a conventional power plant, except, of course, the absence of landuse and the fact that a wind farm always produces electricity:

Key	Value	Comment	Recommendation
power	plant	Defines this node as a wind farm.	mandatory
name	Individual name	The name by which the wind farm is known.	recommended
operator	Operator	Name of the company that operates the wind farm.	recommended
start_date	Date (YYYY-MM-DD)	Date when the construction was finished, using ISO 8601.	recommended
plant:output:electricity	Rated output of the wind farm	The rated output of the whole wind farm. The tagging is consistent with generator:output:electricity=*.	recommended when using simple tagging

Advanced tagging

A wind farm is tagged like an advanced power=plant (as a using type=site), but without any perimeter member. This eases the computing of total wind farm rating, by adding all the generator:output:* values of its generator members.

Way or Node	Role	Recurrence?	Refers to	Recommendation
	generator	1 or more	All wind turbines of the wind farm.	mandatory
	substation	0 or 1	The eventual substation of the wind farm.	recommended

Specific roles

Solar and hydro power plants may contain specific roles, depending on their generator:method=*:

Method	Way or Node	Role	Recurrence?	Refers to	Recommendation
generator:method=dam		dam	1	The waterway=dam delivering water to the hydro power plant.	recommended
generator:method=dam		penstock	1 or more	All penstocks of the hydroelectric dam, tagged as man_made=pipeline, type=water.	optional
generator:method=run-of-the-river		weir	0 or 1	The eventual waterway=weir delivering water to the hydro power plant.	recommended
generator:method=thermal		heliostat	1 or more	All heliostats of the solar power plant, tagged with power=heliostat.	recommended

Generator

A generator is a device that converts one form of energy to another.
For example: mechanical energy or sun light to electricity. 

A power=generator is tagged as a or , on the generator itself, if visible (wind turbine, gas turbine, single solar panel...), or on the smallest building containing it (nuclear reactor, hydroelectric turbine...). Large photovoltaic power plants may group solar panels blocks in a single multipolygon.

This proposal does not change its current attributes. See power=generator for its description.

A new attribute is added, generator:type=*. This attribute is intended to define the type of generator among a single source/method. As a concrete example of what a type is, think about of rendering a map of all nuclear reactors of the same type as those used in Fukushima.

Key	Value	Comment	Recommendation
generator:type	Generator type	The type of generator (see below for possible values).	optional

Non-exhaustive list of possible generator:type=* values

Source / method		Type value	Description
nuclear	fission	PWR	The Pressurized water reactor (PWR) is the most common type of nuclear reactor. PWR is the type involved in the Three Mile Island accident.
		BWR-1 to BWR-6	The Boiling water reactor (BWR) is the second most common type of nuclear reactor. BWR-3 is the type involved in the Fukushima disaster.
		RBMK-1000, RBMK-1500	The RBMK is a type of nuclear reactor which was built in the Soviet Union. RBMK-1000 is the type involved in the Chernobyl disaster.
		VVER	The VVER reactor is a type of Russian PWR used by many countries.
		CANDU	The CANDU reactor is a type of Canadian pressurized heavy water reactor (PHWR). All current reactors in Canada are of the CANDU type.
		CPR-1000	The CPR-1000 is a Chinese PWR.
		EPR	The European Pressurized Reactor (EPR) is a new type of PWR. Four EPR units are under construction, in Finland, France and China.
	fusion	ITER	ITER (International Thermonuclear Experimental Reactor), is the world's largest and most advanced experimental tokamak nuclear fusion reactor, currently being built at Cadarache, in the south of France.
wind	-	horizontal_axis	Horizontal-axis wind turbines (HAWT) have the main rotor shaft and electrical generator at the top of a tower (most common wind turbine).
		vertical_axis	Vertical-axis wind turbines (VAWT) have the main rotor shaft set vertically, and the main components are located at the base of the turbine.
hydro	-	francis_turbine	The Francis turbine is the most common water turbine in use today.
		kaplan_turbine	The Kaplan turbine is a propeller-type water turbine.
		pelton_wheel	The Pelton wheel is another type of water turbine.

Substation

A substation is a part of an electrical generation, transmission, and distribution system.

A power=substation is tagged as an .

This proposal fixes the spelling of power=sub_station, improves its voltage=* attribute and creates a new attribute, substation=*. See power=sub_station for a description of its existing attributes.

In order to distinguish between substations and power=transformers, every power=sub_station should be checked carefully. Indeed, there is currently a lot of confusion between what should be tagged as a substation, and what should be tagged as a transformer. This proposal solves this ambiguity:

• power=transformer represents the transformer device, as a .
• power=substation represents an area that may contain transformers, large enough for a man to enter it. It is thereby tagged as an .

Key	Value	Comment	Recommendation
power	substation	Defines this node/area as a substation.	mandatory
name	Name	The name by which the substation is known.	recommended
operator	Operator	Name of the company that operates the substation.	recommended
ref	Ref	Abbreviation / number of the substation.	recommended
start_date	Date (YYYY-MM-DD)	Date when the construction was finished, using ISO 8601.	recommended
substation	Substation nature	The nature of the substation (see below for possible values).	optional
voltage	Voltage(s)	The different voltages of the substation, ordered from highest to lowest (ex: 400000;225000;63000).	recommended

List of allowed substation=* values

Type value	Description
none	Because there is a lot of technical ways to classify electrical substations, too complex for OSM, all the substations that are part of the electric network itself should not have any susbstation key right now (that could be the goal of a future proposal). This includes power plant substations, transformation substations, distribution substations, switching substations, converter substations, etc...
traction	A traction substation (605-01-06) is a substation whose main function is to supply a traction system (railways, trams and/or trolleybuses). They are often located near a railway.
industrial	Electrical substations may be found inside large industrial sites, forming the hub of their electrical infrastructure.

Transformer

A transformer is a device that transfers electrical energy from one circuit to another.

A transformer is tagged as a . As said above in the Substation chapter, it represents the device itself and shall not be confused with a substation, even smallest ones composed of a single transformer.

This proposal describes the attributes currently in use, that are not explained on the Tag:power=transformer wiki page, adds a location=* key for its physical location, and a transformer=* key to define its purpose.

Key	Value	Comment	Recommendation
power	transformer	Defines this node as a transformer.	mandatory
location	indoor, outdoor, tower, pole	The location of the transformer (indoor: hidden within a building, outdoor: in the open air, tower/pole: suspended to a power tower/pole).	recommended
name	Name	The name by which the transformer is known.	recommended
operator	Operator	Name of the company that operates the transformer.	recommended
ref	Ref	Abbreviation / number of the transformer.	recommended
start_date	Date (YYYY-MM-DD)	Date when the construction was finished.	recommended
transformer	Transformer purpose	The purpose of the transformer (see below for possible values).	optional
voltage	High voltage;Low voltage	The two voltages used at this transformer, highest first, lowest then. A rural 20 kV/400 V is tagged 20000;400 whereas a high voltage 225 kV/400 kV transformer is tagged 400000;225000.	recommended

List of allowed transformer=* values

Type value	Description
transmission	A transmission transformer within a substation connects two or more transmission lines.
distribution	A distribution transformer transfers power from the distribution system to directly connected electricity consumers.
traction	A traction transformer converts electric power from the form provided by the traction network to an appropriate voltage, current type and frequency to supply railways, trams (streetcars) and/or trolleybuses with traction current.
industrial	An industrial transformer converts electric power from the form provided by the electrical power industry for public utility service to an appropriate voltage, current type and frequency which is needed by small industrial facilities (e.g. bakeries).

Deprecated tags

Deprecated tag	Used for ?	New tag(s) to use
power=station	Power plant	power=plant
power=station	Substation	power=substation
power=sub_station	Substation	power=substation

Life cycle management

Power features under construction

Large power features under construction are tagged with power=construction and construction=*, in the same manner highways and railways are:

Key	Value	Comment	Recommendation
power	construction	Defines this feature as under construction.	mandatory
construction	plant, substation, generator, line, cable	The power feature under construction.	mandatory

Decommissioned power facilities

A power plant, generator or substation is decommissioned when it does no longer produce/transport energy.

Decommissioned power plants, generators and substations are tagged with these additional attributes:

Key	Value	Comment	Recommendation
disused or abandoned	yes	Defines this feature as disused (no longer used, but still maintained and has repairs made), or abandoned (no longer maintained). When a disused facility has been reconverted into a new amenity=* or man_made=*, the disused: namespace shall be used for its power key (See Key:disused for documentation).	mandatory
end_date	Date (YYYY-MM-DD)	Date when the facility was stopped, using ISO 8601.	recommended

Undergrounded power lines

Undergrounding refers to the replacement of overhead power lines with underground cables.

More and more power lines are undergrounded. When it happens, the power line should be replaced by power=cable (See its wiki page to view its attributes).

If the power line is still visible on aerial imagery, power towers/poles may be replaced by a single note=* explaining the power line has been undergounded, to avoid future errors from new mappers, unaware of this fact.

Examples

Single-site facitilies

'Single-site' power plants are ones where all, or most, of the equipment is found on a single site, often with a clear perimeter such as a fence unlike wind-farms and some other types which are distributed without a clearly demarcated perimeter.

Fukushima

Fukushima Daichi is a disused single-site power plant. Each of the four individual nuclear reactor is tagged with power=generator, generator:type=BRW-3 and the designed power out generator:output:electricity=* value together with disused=yes). The power plant itself is tagged with landuse=industrial and power=plant with a rated output at plant:output:electricity=0 because all generators are now out of use. A power=plant can also created with the roles perimeter and generator for the elements.

Olkiluoto

Olkiluoto is a nuclear power plant with a new reactor under construction (the one on the left). It should be tagged with power=construction, construction=generator), and generator:type=EPR (it is in fact the first reactor of this new type). Its generator:output:electricity=* value is set, but not (yet) taken into account in plant:output:electricity=* computation. The various substations are also tagged. The generators, plant and the associated substation are included in the relation.

Thémis

Thémis is an example of a solar thermal facility using heliostats to direct solar heat towards a single tower. The individual heliostats are tagged with power=heliostat. The generator is the solar tower, tagged as a man_made=tower, power=generator, generator:source=solar, generator:method=thermal and generator:output:electricity=*. The perimeter of the facility is tagged with landuse=industrial. These elements are then gathered into a power=plant with roles of 'heliostat', 'generator' and 'plant'.

Parker Ranch

Parker Ranch is a small example of hybrid power plant combining different sources. Electricity is generated by 5 wind turbines (generator:source=wind) and a photovoltaic array (generator:source=solar, generator:method=photovoltaic).

Dispersed facilities

Middelgrunden

Middelgrunden is a good example of offshore wind farm. Wind turbines are gathered in a single power=plant with the role generator. There is no perimeter.

Hoover Dam

Hoover Dam is a good example of a complex hydro power plant. The whole facility is tagged as the power=plant  Hoover Dam (XML, check, manage, JOSM, history, view, gpx ), with these main members:

• With the role dam: The dam (waterway=dam).
• With the role generator: The 17 electricity-producing Francis turbines (power=generator, generator:source=hydro, generator:method=dam, generator:type=francis_turbine, generator:output:electricity=61.5 MW to 130 MW) of the Arizona Wing (name=A1 to A9) and Nevada Wing (name=N1 to N8).
• With the role generator: The 2 internal Pelton wheels, providing power for the facility itself (power=generator, generator:source=hydro, generator:method=dam, generator:type=pelton_wheel, generator:output:electricity=2.4 MW, name=A0, N0).
• With the role substation: The dispersed substations of the facility (power=substation).
• With the role penstock: The penstocks that deliver water to the turbines (man_made=pipeline, type=water).

All of its members are tagged with operator=U.S. Bureau of Reclamation and their respective start_date=(1936 to 1961). The total rated output is equal to plant:output:electricity=2080 MW.

Features/Pages affected

If approved, this proposal would impact:

• Tag:power=plant: Create this page and explain its usage.
• Key:plant:output: Create this page and explain its usage.
• Key:substation: Create this page and explain its usage.
• Tag:power=sub_station: Rename it to Tag:power=substation, add substation as a new substation attribute.
• Key:generator:type: Create this page and explain its usage.
• Tag:power=generator: Add generator:type as a new generator attribute.
• Tag:power=station: Explain why is it deprecated, and display links to Tag:power=plant and Tag:power=substation.
• Template:Map Features:power: Add power=plant as a map feature, remove power=station, rename power=sub_station to power=substation.

Tools/Renderers affected

If approved, all tools and renderers would have to take into account power=plant and the new spelling of power=substation. Some would have specific things to do.

JOSM

• First of all, resolve ticket #6436: Fixed in revision 4210 (included in JOSM tested 4223).

Potlatch 2

• First of all, resolve ticket #3779

Mapnik

• First of all, resolve ticket #3266

ITO Map

• The color of substations, based on their substation=*.

See also

• Proposed features/Power plants: The proposal that introduced power=generator in 2007.
• Proposed features/generator rationalisation: The proposal that introduced generator:source=*, generator:method=* and generator:output=* in 2010.

Comments

Comments are welcome on the Talk page :)

Voting

To vote use {{vote|yes}} or {{vote|no}} and sign with -- ~~~~

• I approve this proposal. -- Lzhl 13:56, 27 April 2012 (BST)
• I approve this proposal. -- PanierAvide 16:00, 27 April 2012 (BST)
• I approve this proposal. -- Michi 19:07, 27 April 2012 (BST)
• I approve this proposal. -- Surly 06:13, 28 April 2012 (BST)
• I approve this proposal. -- Silver87 07:15, 28 April 2012 (BST)
• I approve this proposal. We need a cleaup of bad terminology. BTW the start of voting has not been announced on [tagging] as far as I have noticed --polderrunner 08:00, 29 April 2012 (BST)
• I oppose this proposal. Existing power-key is defined enough, we're not Power station engineers or something like that.--R-michael 16:11, 2 May 2012 (BST)
• I approve this proposal. -- T99 22:48, 3 May 2012 (BST)