Rise of Renewables

The share of renewable* power in the European** generation mix is growing.

Which is very positive news! The captivating image below reveals more details.

We use a t-plot in polar coordinates here — a visualisation that facilitates examining recurring seasonal patterns and long-term trends. Starting from January on the right, the time series loops counterclockwise around the circle that represents a full year. Concentric reference lines are shown at 10%, 25%, and 50%.

Here, we observe an overall increase in the share of renewables in recent years. In 2016, it tended to fluctuate at 30% whereas in 2024 and in 2025 so far, it was around 50%. The plot also reveals fluctuations on a daily, weekly, and seasonal basis. Their magnitude is growing as the share of renewables grows.

Another way to get insights about long-term trends is by checking how likely was a certain share (%) to occur in the time series. This visual aid is known as a frequency histogram (Fig. 2).

Here we notice that the peak of frequency (a.k.a. mode) in 2016 was 26%, while in 2024 it is at 50%. Other measures of central tendency were constantly growing over these years too: mean (from 33% to 49%) and median (33% - 48%). But also grows the dispersion of data, e.g. standard deviation from 5% in 2016 to almost 8% in 2024. As of November 15, 2025 has its mode, median, mean and standard deviation at 47%, 49%, 50% and 9% accordingly.

Due to the highly variable and poorly predictable nature of some renewables, balancing the power markets in such a way that maximises their utilisation is a challenging task.

It is likewise important to know when, where, and which of renewable power capacities, both present or yet to be built, should be utilised to ensure long-term sustainability and green transition of power systems. The matter gets even more complex considering the uncertain geopolitical circumstances and climate change.

Therefore, more ambitious endeavours are necessary in research, practice, and policymaking to tackle the challenge. The efforts of developing renewable power technologies, elevating energy efficiency and flexibility on the consumer side, tuning energy economics and politics, as well as more accurate predictions of climate variations, are among the key enablers here. An absolutely green power system is still far away and may never happen, but the progress is already significant and something to be proud of.