Essentially it's not an isolated market, but part of a bigger whole.
As an example imagine a village that constituted 1% of the population of a country. The village was 100% renewable, and the country was 0% renewable. If the village disconnected its grid, in isolation its prices would be dictated by its renewables. But if its connected, its renewables just get traded on a market with marginal prices. If a person elsewhere in the country has more expensive generation, they'll but your cheap renewables at their price level. Thus the village will experience high prices like everyone else.
Now suppose Germany is that village in an interconnected EU market. Of course the numbers from my example are exaggerated, but the point remains: Germany's renewables aren't enough, if pricing is set at a much larger market, with fewer renewables.
Today about 20% of Germany's electricity was exported. While only about 6% of its demand came from gas. In other words if Germany was disconnected, it'd have needed no gas, and thus prices would've been lower.
Of course disconnecting isn't a good idea for other reasons, as on other days Germany imports. And Germany's ability to export its renewable excess generates significant revenues, creates incentives to build more renewables, and offsets emissions and pollution in other countries, too.
But long story short, it'll take more for one part of the whole to go renewable. As the EU is generally transitioning towards renewables we see a decoupling happen.
Essentially it's not an isolated market, but part of a bigger whole.
As an example imagine a village that constituted 1% of the population of a country. The village was 100% renewable, and the country was 0% renewable. If the village disconnected its grid, in isolation its prices would be dictated by its renewables. But if its connected, its renewables just get traded on a market with marginal prices. If a person elsewhere in the country has more expensive generation, they'll but your cheap renewables at their price level. Thus the village will experience high prices like everyone else.
Now suppose Germany is that village in an interconnected EU market. Of course the numbers from my example are exaggerated, but the point remains: Germany's renewables aren't enough, if pricing is set at a much larger market, with fewer renewables.
Today about 20% of Germany's electricity was exported. While only about 6% of its demand came from gas. In other words if Germany was disconnected, it'd have needed no gas, and thus prices would've been lower.
Of course disconnecting isn't a good idea for other reasons, as on other days Germany imports. And Germany's ability to export its renewable excess generates significant revenues, creates incentives to build more renewables, and offsets emissions and pollution in other countries, too.
But long story short, it'll take more for one part of the whole to go renewable. As the EU is generally transitioning towards renewables we see a decoupling happen.