Main keys to wind and solar production in 2018 in Spain

On January 23rd, the record for wind power production in Spain was broken with 373 GWh in 24 hours and today we still have days with a lot of wind, which means that a very important part of the electricity demand is covered with wind power. It is in these days of records when the media echoes the important contribution that renewables already have in the national electricity system. It is also a good time to make a brief review of what has been 2018 in terms of wind and solar production in Spain.


The truth is that the annual data for 2018 have not yet been published but thanks to Entso’s great site, we can now have all the electricity generation data in Europe in real time, so it is possible to make our own analysis. And that is what I have done here: I have downloaded the daily wind and solar production throughout 2018 in order to draw some conclusions.

So let’s first look at the daily wind and solar production throughout the year in Spain:


Several aspects catch our attention

  • The seasonality of both is clearly appreciated but with the good news that it is complementary: in summer there is less wind but it is when more solar is produced. This is very important because the solar will grow in installed capacity and better compensate for low summer wind production.


  • It is confirmed that wind is much more variable than solar. The saw curve of the wind is in some cases spectacular, such as last February 15, which in just 48 hours went from generating almost 300GWh to less than 50GWh.


  • The maximum daily wind production was on March 24. Let’s see the detail of generation that day on the REE page:

As can be seen, wind supplied 53% of the demand. Another curious detail in how the daily peaks are attended: the midday peak is covered with the contribution of the solar, but the 21h peak, as there is no solar, has to be covered with hydraulics (abundant in March).

  • It is curious that the maximum solar production was on May 16. This may be due to the fact that in May there are already many hours of sunshine, but it is still not as hot as in summer, so the modules work better and produce more.


Another aspect that is strongly emphasized these days is the relationship between the level of renewable production and the price of electricity. Although it is a rather complex subject (AEE’s page on this subject is highly recommended for those who want to go deeper), the relationship is clear: the more renewable, the lower the cost. Let’s see how it was in 2018:

It is very illustrative that the peaks in the daily price of electricity coincide exactly with the inverse peaks of wind production: in March with the peak of wind was reached in minimum price of electricity and vice versa in September.


As a curiosity, let’s look at the pattern of wind and solar generation in 2018 of the European country with the highest installed capacity: Germany.

Germany has been the first European country to reach 1TWh of daily production with wind power. It happened on December 8 and was thanks to the increasing contribution of offshore wind. And once again the variability of the wind is evident when with a separation of 34 calendar days we go from the historical record (8-Dec) to the annual minimum (11-Jan).


This analysis confirms with data several things we already knew: the direct relationship between renewables and lower electricity prices, seasonality and variability in production and the increasing weight in the generation mix.