Visualizing Loads is unclear

[nickhalmagyi]

In the attached image from the Energy page, Ive selected solar and loads, but one could also select any source and loads for the same effect. As you see it looks like the solar is negative and positive, the loads are not being represented in their color correctly

[nickhalmagyi]

Just thought I would add, I think the Emissions page is an accurate "compound line graph" which accommodates negative values (from Land Management), but the Energy page seems to be pretty confusing regarding the negatives coming from the loads.

[chienleng]

that's definitely deliberate for the Energy view when we initially designed the visualisations. Emissions are just a summation of emissions from all the industries, and negative emissions doesn't really negate the emissions already emitted. We wanted to show a more interesting view of how a region works in the NEM. (i.e. the total demand, rather than total generation).

It does display better in a region like SA, compared to the NEM region.

We try to have many options to let people play with the visualisations, and we did initially thought of allowing some form of stacking options but haven't got around to exploring more detail in that yet. For now, you could 'hover' on each load and it will highlight the negative areas or just select the Loads.

Which part is it confusing in your mind? Should we be explaining more on how the loads affect the visualisations?

[nickhalmagyi]

Hi, thanks for your thoughtful reply

So I think there are two different ways that stacked line graphs can being displayed.

Case 1:

This is used on the Energy page, a simple example has just battery charging/battery discharging

The battery charging is a positive contribution and the battery discharging is a negative contribution. The rules of the graph are

1. All the negative contributions appear below the x-axis.
2. Then the positive contributions appear above the lowest edge of the negative contributions
3. The total contribution is the top most edge of the battery charging contribution, regardless of whether that is above or below the x-axis.

As a result there are some regions where the positive contributions appear on to color over the negative contributions. In the example this can be observed by hovering over the battery charging/discharging to highlight just that component.

Case 2:

This is used on Emissions page, Ive included an example with electricity and Land Management.

The rules of the graph are:

1. The positive contributions appear above the x-axis
2. The negative contributions appear below the x-axis
3. The total is indicated with an additional line, representing the sum of the positive and negative contributions.

Comments

I have found that case 2 is perfectly clear. I have found that for several reasons, case 1 is confusing. When there are only positive or only negative contributions, both cases are the same (such as for the second image you posted with only loads selected).

One reason I found case 1 confusing, is that positive contributions can color over negative contributions and thus hide them, which is what happens in the image I first posted. When this happens its confusing to me why a positive contribution is appearing below the x-axis.

Another reason is that I found it very hard to understand how the total contribution is represented. For example, if I select a small portion of the graph from above

then it seems to me that it is impossible to know how the total is represented. It is ambiguous whether the dark blue is a positive or negative contribution. We know that the light blue is a negative contribution and the dark blue is positive but that is not clear from the graph. So the total is in fact at the top edge of the dark blue contribution but one might also think that the total is at the bottom edge of the graph.

In my opinion if the Energy page used case 2 like the Emissions page does, it would be clearer.

[aleith]

I must admit when I first started looking at SA graphs when the new loads feature was introduced, reading the graph and being confident about the implications of what I was seeing was difficult. I nearly logged bugs at the time b/c I got so confused at times. I appreciate the explanations in this thread, certainly clarifying. Probably needs a dedicated user documentation page, as opposed to the developer docs linked to with a button in the footer.

Take these two graphs same data, only difference is turning the Rooftop PV data on/off.

I takes quite a bit of thought as to why the yellow is covering over some of the export purple regions and not others, and why some PV appears to be contributing exports while other parts do not.

I'm not sure of the best way to resolve this, it's okay once you understand why I guess. Certainly needs a documentation page.

[chienleng]

Agreed with all the points stated.

• I would recommend another option to toggle how the stacked area gets displayed so when viewing Loads, it's easier to see the difference.
• more docs