PowerLight

Project PowerLight
Show energy mix of dutch power generation as a pie chart on a LED ring
Status	In progress
Contact	bertrik
Last Update	2022-07-12

The concept

Draw the current power generation-mix as a kind of pie chart on a LED ring light, with colors representing a fraction of a specific power generation source.

For example:

• blue: wind power
• yellow: solar power see below
• green: power from biomass see below
• purple: power from nuclear
• red: fossil
• grey: other

Power generation data

There is no open data available with reasonably complete power generation fractions!

The solar power problem

In particular the solar power fraction is incomplete, but also the biomass figures are missing. See:

• https://berthub.eu/articles/posts/dutch-electrical-power-figures-2/ (text)
• https://energy-charts.info/charts/energy_pie/chart.htm?l=en&c=NL note how the solar part is tiny

There is a model to estimate this fraction at https://api.netanders.io/, however you cannot use this API without a key (and you can't just get a key).

Some ideas to fix this gap somewhat:

• Correlate official reported solar data with the model, and extract a kind of tennet-reported->best-guess-actual multiplication factor
• Use yesterday's solar prediction data from ENTSO-E. The number seen here seems to correlate reasonably well with the number shown at https://energieopwek.nl/ (which bases itself on the netanders model)

Information about ENTSO-E generation domain API: https://transparency.entsoe.eu/content/static_content/Static%20content/web%20api/Guide.html#_generation_domain

Hardware

Parts:

• LED ring light https://nl.aliexpress.com/item/1005003798658173.html
• Wemos D1 mini with an ESP8266

Software

The software consists of two parts:

• backend part that collects the power generation data
• light part that visualizes the power generation as fractions on a LED ring

Backend

Source code: https://github.com/bertrik/energymix-server

In progress, run as a REST-like resource at http://stofradar.nl:9001/energy/latest (1-minute rate limit)

Returns a JSON-structure like:

{
  "time": 1657057500,
  "total": 9122,
  "mix": [
    { "id": "solar", "power": 0, "color": "#FFFF00"},
    { "id": "wind", "power": 4, "color": "#0000FF"},
    { "id": "fossil", "power": 86, "color": "#FF0000"},
    { "id": "nuclear", "power": 5, "color": "#FF00FF"},
    { "id": "other", "power": 4, "color": "#444444"},
    { "id": "waste", "power": 1, "color": "#444444"}
  ]
}

• time is a unix time stamp in seconds, representing the end of the 15-minute period that the power figures refer to
• total is the total current electrical power (megawatt), suitable for display (on a numeric display inside the ring for example)
• energymix is an array of power sources, each with:
  • a short unique id
  • most recent known power (megawatt)
  • hex color, for display on the led ring

Light

Source code: https://github.com/bertrik/PowerLight