Commission dates of power plants in China

Visual Design
#1

Hello! I am trying to create a map which shows all power plants in China and colour code them by it’s commission date. Each decade has a different stepped colour from dark red to dark blue. Some might be missing as some of the power plants were missing commission dates from the data set.

Visulization:

china powerplant commision
china powerplant commision1220×711 107 KB

Visual Design Type: Map
Name of Tool: Tableau
Country: China
Year: All Available
Visual Mappings:

  • The columns and rows are made up of the longitude and latitude in order to create the map.
  • The points show each power plant with an available commissioning year.
  • The colours indicate the decade the power plant was commissioned, starting from dark red in the 1940’s to dark blue in the 2020.
  • The fuel types used is also available when a point is hovered over with the mouse.

Unique Observation:
The purpose of this visualization is to show all the power plants in China along with the year they were commissioned. A lot of the power plants were commissioned between 2000 and 2020. The power plants commissioned between 1960 and 1980 are relatively spread out.

Data Preparation:
I needed to filter out the rest of the countries in order to compile all of China’s data.

Source: http://datasets.wri.org/dataset/globalpowerplantdatabase

I am unsure whether this is the best way to visualize the data so I would like some pointers like whether the colour palette is the okay and how I should represent the fuel type each power plant uses without the need of hovering over the point.
Although you can zoom in to see each point clearer, from the initial image a lot of points are clustered together so it is difficult to spot individual ones. Is there a better way to visualize these points so it is easier to see with the default scale?
If anything else sticks out please do not hesitate to tell me.

Thank you in advance and all criticisms are welcome!

#2

Hi,

I’ll try and answer your questions.

  • For this visualisation and the given task, it’s a reasonable way to label the points without showing too much colour i.e. have a colour for each year. I would increase the steps of the colour saturation to make points in one saturation a bit more distinguishable from one another.

  • To show the fuel sources without hovering (tooltip), you could add a label next to each point, but given the number of power plants, this isn’t a good option. You could change the colour based on the fuel sources, but this will be a different task itself (showing fuel distributions in china). This could be added in as a second view though.
    If you really wanted to have all this in a single view, you could use a scatter plot showing the commissioning years on one axis while having another attribute on the other (total electricity output, output for one year, estimated generation etc.), then colour each point based on their fuel source.

  • For your cluttered points, I think you could decrease the opacity of the points so that points covered by overlapping points can be seen (from your initial view).

Generally, you can tell that most of the power plants have been commissioned between 1980 - 2020 based on their colour saturation and the older/ newer power plants are at the opposite end of the colour saturation scale. The visualisation doesn’t convey much information from the data set (unless given via tooltip), but it’s pretty good given the task you’re trying to achieve.

Hope you found this useful!