There is enough data showing, that about 80% reneweables in the mix are possible without larger storage facilites, if the gaps are covered by gas power plants which can change their output power quick enough to react on the demand. Neither coal nor nuclear can do this.
That Germany is missing its emission targets has two reasons. One is, that coal is not ramped down aggressively enough, which has mostly economical reasons, coal is to profitable for the power companies, but recent forced closures of some coal plants shifted a bit here. And the other elephant in the room is the raising fuel consumption for transportation. Going electric for cars would have a large impact there.
Let me ask you this, if solar is capable of replacing fossil fuels, why did Germany sign a multi-decade/mult-billion-euro deal to buy Russian gas?
Germany is part of the European power grid, so there are times, when power is imported to compensate for local over- and underproduction. As Germany is in the middle of Europe, far more power is conducted across of Germany. You cannot count French nuclear power as in import, if the same amount of power is exported to Austria at the same time (a very common situation). Germany is a net power exporter.
Gas is important in two way: first of all, it is way cleaner than coal, so it is the best short term replacement for coal. Germany almost has enough (currently mostly idle) gas power plants to completely replace coal short term. As long as there are no mass storage facilities, gas is needed as the gap filler for the times when neither wind and solar can power the grid. As the production capacity grows, these gaps are going to get increasingly smaller. It remains to be seen what is the best long-term solution, either to grow large storage facilities to get to 100% reneweables or allow like 10% gas in the mix.
And there aren't.
>gas is needed as the gap filler for the times when neither wind and solar can power the grid.
This is the entire point!! Wind and solar can't replace fossil fuels. So what Germany did was replace non-CO2 emitting nuclear power with CO2 emitting power generation (natural gas and coal). I guess fighting global warning is less important than satisfying irrational German paranoia against nuclear.
>As the production capacity grows, these gaps are going to get increasingly smaller.
The sun will start shining at night?
The sun will start shining at night?
That sentence did a huge disservice to your post. Of course the sun doesn't shine at night. But no one wants to replace all energy production by solar alone. Wind is the companion of solar, both are roughly the same size in Germany. Wind is what delivers the power at night (where electricity consumption is lowest) and solar adds the power for the additional requirements during daytime.
They aren't. We agreed that wind/solar is not capable of serving as the base power generation of a modern economy. Lack of city-scale battery technology, and the variability of solar and wind precludes this use case.
So what Germany did was remove a non-CO2 emitting power source and replaced it with a mix of solar/wind AND CO2-emitting power generation (via existing coal plants, new gas plants, and importation of coal-based power when they need it).
If the name of the game is to cut CO2 emissions as much as possible, you're at net negative. It necessarily means that had you not closed down nuclear power plants, you would have cut MORE CO2 emissions than you do now. That's just a statement of fact.
And this is my problem with anti-nuke policies. Implicitly the anti-nuke activists are saying that cutting CO2 emissions isn't as important as preventing expansion of nuclear power or even keeping existing plants running. Consider this and cry for our civilization: had the developed world doubled-down on nuclear power in the 60-70s to the same level as France, we would have prevented trillions of tons of CO2 from being emitted into the atmosphere. That could have bought us a few extra decades. I am convinced that history will see antinuclear view as more destructive than right-wing global warming denialism (which on balance does not actually do anything).
>Of course the sun doesn't shine at night. But no one wants to replace all energy production by solar alone. Wind is the companion of solar, both are roughly the same size in Germany. Wind is what delivers the power at night. Meaning that you have to overprovision your infrastructure to supplement periods of low output.
Again, this is a disingenuous point. The problem with wind and solar is not only variability but also the fact that peak generation does not match peak consumption. If peak wind generation is at 3am, it doesn't do our society any good because we need power at 6pm. Worse than that, solar and wind generation profile changes with weather and seasons.
So no, it's not simple as saying: Solar peaks during the day, and Wind peaks during the night and therefore they complement each other ... because they don't.
Replacing both with domestic non-fossil solutions is near-impossible in the medium term unless nuclear forms a big part of the baseload - heating on those winter nights where the sun doesn't shine but electric heat exchangers work full tilt, and generation for those electric cars charging throughout the winter night.
Besides, gas is a cheap, fast way to replace coal with drastically reduced carbon emissions.
I am no expert, and I think neither are you, so we are just making some small talk here, but: I think we don't have the tech to go all in on renewable. Solar is cool and all, but where do we store the energy? Batteries don't scale at a global level (for now). I mean look at Germany: they tried. They got off nuclear and now they emit more CO2 than when they started because they had to revert back to coal.
I see no easy solution to this. Not for now. And for sure it's not something like "let's just switch to wind and solar and we are good".