[RFC] Split out capacities from zones.json to facilitate historical capacities

[VIKTORVAV99]

We now have historical production information in the map but I found myself missing seeing the installed capacities on these new time periods.

So in this RFC I request we split out the capacities from the zones.json file into a new capacity.json file.

This new file would only contain capacities (either just zone capacities or zone + exchange capacities) but would allow for historical values.

I propose we adopt the same structure as for the co2eq values and allow the capacity object for each zone to be either a single capacity object or a array of objects containing the capacity object and a datetime (and possibly source).

[VIKTORVAV99]

Another small benefit from this would be auto labeling for PRs that affects the capacity 🙂

[Kongkille]

I like this idea,

For context, when we added historical view we disabled capacity because the live one of course is not valid for the full 5 year period. Having multiple capacity values seems like a good idea however there are some things we'd need to consider

Off the top of my head:

• Which time periods are capacity valid for, eg for a full year, or less?
• Do we accept multiple different sources for capacity
• How do we update this retrospectively with the current capacities, i.e. some of them may be quite recent whereas others may be from a few years ago

Also adding this discussion for some context on splitting out zones.json #2962

[VIKTORVAV99]

I like this idea,

For context, when we added historical view we disabled capacity because the live one of course is not valid for the full 5 year period. Having multiple capacity values seems like a good idea however there are some things we'd need to consider

Off the top of my head:

• Which time periods are capacity valid for, eg for a full year, or less?
• Do we accept multiple different sources for capacity
• How do we update this retrospectively with the current capacities, i.e. some of them may be quite recent whereas others may be from a few years ago

Also adding this discussion for some context on splitting out zones.json #2962

My idea was to use the same structure as the co2eq intensities so:

• A capacity would be valid until a newer entry is found, this would also allow us to backfill capacities without much of a problem.

"capacities": {
  "DK-DK1": "capacityObject" // This would be valid for live data. (current functionality) 
  "DK-DK2": [
    {
      "datetime": "2020-01-01" // This would be valid from 2020-01-01 to 2020-12-31.
      "capacity": "capacityObject"
    },
    {
      "datetime": "2021-01-01" // This would be valid from 2021-01-01 to indefinitely.
      "capacity": "capacityObject"
    },
  ]
}

• I think we might have to accept multiple sources as say ENTSO-E might not have all the historical data we need. That is why I propose we include a source field as well.

{
  "datetime": "2020-01-01"
  "capacity": "capacityObject"
  "source": "sourceString" // or potentially an array of strings
  "_comment": "full_source_or_clarification" // Optional
}