Switching from nuclear power to renewables has been a topic of discussion for quite some time now in German media. The main concern is that this transition might not be possible without having to dig into the power storage reserves or rely on coal use.
A study conducted in Germany by the Association for Electrical, Electronic and Information Technologies (VDE) , looked into the influence of intermittent wind and solar power on the grid, and whether electricity needs to be stored. They simulated five scenarios, where the outcome was only determined by the flexibility of dispatchable power generators. The estimated that with a maximum of 10% increase of power cost, when the share of renewables is 40%.
According to Renewables International, these results indicate that there will not be a need of excessive power storage, given that the targets for wind and solar power generation are met. Germany should produce 40% of its electricity using renewable sources, when currently this number is 25%. In Denmark, this has already been achieved without additional power storage infrastructures.
The targets for 2050 indicate between 40 and 80% of energy to be produced using renewables. To meet these, Germany would need up to 18% GW of seasonal power storage, which would cause around 10% increase in current energy prices. The final 20% however, according to the German engineers, would be at twice higher cost due to the bigger need for power storage.
As the chart indicates, nuclear power generation is to be fully withdrawn due to national polices, while coal power would drop and nearly disappear when the country reaches the 80% target, although there is no national policy set yet.