Revised visualization
Original
What works and doesn't work with the chart?
First of all, while the point is interesting, it's meant as a comparison. However, one of the confusing things is the size and scale of the scope: few people are going to know exactly what EU-27 means: it's only after digging a little that we can see that it refers to the EU after the UK left.
However, the labeling also gives rise to many questions: what are renewables? The way that I understand renewables is that it's solar, wind, and geothermal energy. If that's the case, why are wind and solar on here as a separate category? What gets even more confusing is the idea of EU-27 as a whole doing this: looking further into the dataset gives me a chance to see exactly what the statistics are.
Renewables are a combination of Bioenergy, Hydroelectric, Solar, Wind, and other renewables.
Fossil fuels are a combination of Gas, Hard Coal, Lignite (soft coal), and other Fossil Fuels.
As a result, this is a chart that is combining two different stories. The first is how Renewables are comparing to Fossil Fuels: i.e., sum vs. sum. The other is about the most popular individual categories of each compare: Wind and Solar vs. Coal.
How can you make it better?
To properly address this type of story, we need to make a few changes to how it's structured. First, we need an overview of the subject: given that the chart title is "Renewables overtake fossil fuels," we need first to tell that story. To do that, we need to have a better visual comparison between the two categories: for that purpose, I first created a stacked bar chart to provide an overview of how all possible renewable energy sources stacked up against all possible fossil fuels, and when the shift from the majority of energy being generated by renewable energy took place.
The second chart is a subset of that data, which shows the types of renewable energy and which renewable energy sources grew the most over this period.