When playing with the data of Agorameter, I got the impression that Germany was exporting electricity to its neighbors in order to deal with the consequences of their increasing share of wind and solar energy. In most cases there were two distinct export peaks, the biggest one at noon, a smaller one at midnight. Unless there was a lot of wind, then the peak was hidden in a higher peak. At first glance the export followed somewhat solar or solar + wind. That’s why I had the impression that they just exported their overproduction to the neighboring countries.
Therefor it was a surprise to me to read the following in the brochure 9 myths about the German Energiewende debunked (translated from Dutch):
Lignite power mainly leads to an increase in electricity export.
This is a real remarkable statement. I hadn’t seen that in the data, maybe even the contrary. Just look at the data from the last seven days (relative to yesterday, when I started writing this post)
and compare this with the import/export balance (purple line) of the same period:
The first three peaks at noon are clearly visible. After that, wind slowly picked up and the fourth solar peak is hiding in a blob of wind/solar. Then a sharp drop downwards because there was no sun anymore and wind dropped. Then wind picked up again, together with solar so the next two peak resided in a blob. Then the wind dropped again and the last export peak at noon is visible again. Just eyeballing the two graphs gives me the impression that the im/export balance is following wind and solar. Certainly not lignite, because the production was pretty stable the whole time.
Curious as I am, I wondered how much agreement there actually is. One could get some impression from viewing the previous graphs, but is that impression also correct? I couldn’t find any download function other than in picture format, so I found myself transcribing all the data points manually into Calc. A tedious job that took me a while, but now I could display the data in several ways and at the same scale. Right away, it very quickly became clear that the import/export balance was always at the export side during the entire seven days period. So Germany exported more than it imported every single moment.
When I then compare solar production with balance of imports and exports I get this:
Clearly showing that the first three export peaks followed solar production. The third production peak even snuggly fits into the im/export-balance peak. The next peaks show that the influence of wind overpowers solar. In the last peak we see the influence of the diminishing wind and solar production.
When I add wind with solar, I get this:
The im/export balance follows rather nicely solar + wind energy production. Not everything is exported, but at least a fair share. Knowing that biomass, nuclear, hydro, lignite, gas are used as baseload and coal for balancing the load as good as possible, then wind and solar are the only sources that could account for the difference.
Finally, the comparison with lignite energy production:
No, that doesn’t follow even close. On the contrary, lignite also seems to be used for some balancing. So if I would have to guess what type of energy Germany is exporting, then I know what to choose. And no, it is not lignite energy production, as Greenpeace seems to think.
But in the end, whether the exported energy comes from coal, lignite, wind or sun is in fact the wrong question. Nobody can differentiate between the electricity from these sources anyway. The big question is WHY that power gets exported. The point is that these exports, whatever source it comes from, is the logical result of Germany’s choice of integrating intermittent power sources on their grid without the ability to balance that power. It is the consequence of how they deal with the growing share of intermittent energy. Therefor, I personally think it doesn’t matter where this surplus comes from, it is a direct result of their policies that promote wind and solar energy.