Net wind energy percentage in Germany in 2017 was 18.9%. And that's a fact. Which clearly voids your argument. Yes, there are limitations how high it can go and I don't expect it to be anywhere near 100%. But it's clearly a huge source of energy already and it will increase even more in the coming years.
The reason why it totals 1.5% is because it costs money to replace existing power sources and the lobby power of the coal industry is still huge. It has nothing to do with solar energy itself.
The renewable parts of that is bound to go down: As part of the push to renewables, when spinning up capacity, you get prices guaranteed for 20 years. The different to market rates is spread across the whole market ("EEG Umlage", "renewable energy law contribution").
But: that law is approaching 20 years now and so in 2021 the first installations will drop out of that subsidy scheme. Prices and guaranteed rates were dropping ever since, and so will the subsidies - with a delay of 20 years.
> there seems to be no choice for the heavy industry than to use coal
Comparing the numbers in 2000 and 2017 (https://de.wikipedia.org/wiki/Stromerzeugung#Bruttostromerze...), coal used to account for more than 50% of power generation in 2000, down to 36.6% in 2017. Even in absolute numbers to account for the rise in total power production, coal is less in 2017 than in 2000. Petrochemicals are up from 9.5% to 14.1% though.
Non-regenerative power was 436.5 TWh in 2017, down from 538.7 TWh in 2000.
The stats you have provided are the numbers for the whole electricity generation, while I was talking of the heavy industry alone. I am not an expert, but AFAIK for steelmakers in particular it is crucial to have a reliable constant power supply, which neither solar nor wind can provide (let alone steel production itself relies on coal).
18% at a horrible cost and not for all uses of energy. The german energy politics is a diaster. You are confusing reality with potential. Most countries get energy outside their own countries just like Denmark who are even higher on wind but still had to get coal based energy from germany because of the lack of wind this summer. Solar and wind isnt even close to solving actual energy needs which includes transportation one of the biggest co2 immitors.
And no realistic fuelcell technology or disrributed grids.
France does not have enough nuclear capacity for high winter electricity demand and it has too much nuclear capacity relative to domestic demand in temperate weather. It ends up reliant on imports from Germany in winter time and exports surplus electricity at times of low demand. As I write this, France is importing 6.7 GW from Germany: http://www.gridwatch.templar.co.uk/france/
If France were forced to disconnect from its neighbors, its electricity would be more expensive and/or more emissions-intensive. It would need more fossil combustion to deal with seasonal demand swings and/or it would get less utilization out of its nuclear reactor fleet. The same goes for Germany, of course: electrically isolating itself would also increase costs/emissions. Germany and France both rely on international electrical connections to improve utilization of their non-combustion electricity sources. Both use imports to meet part of their electricity demands. Both are net electricity exporters over the course of a full year.
The reason why it totals 1.5% is because it costs money to replace existing power sources and the lobby power of the coal industry is still huge. It has nothing to do with solar energy itself.