[belorn]

Looking at this from a historical perspective, Nuclear with other types of primary generation did not generate a highly variable grid. Its a recent phenomena in Europe that has caused spot prices jumps from negative to 2$ per kWh, which the primary blame being put in volatile energy production.

If we are claiming that nuclear is similar to renewables, we should expect regions where nuclear is being decommissioned to have an increase in renewables with no increase in natural gas consumption. This is however not the case. This has been demonstrated by the decommissions of nuclear plants in Germany and Sweden, with fossil fuel emissions being increased as a direct results. To take Sweden as an in-depth example, after the decommission of their south based nuclear power plant the two major natural gas plants in the region went from operating a few times a year to running almost 24/7, only shutting down briefly during optimal weather conditions. They are now the highest source of pollution in that region, and more natural gas plants are being planned for construction. As a result the government funding for the "reserve energy" has increased significantly (ie, fossil fuel subsidies).

[ZeroGravitas]

Germany's gas generation has indeed been flat while nuclear and coal is being phased out, so I guess you've very strongly proved my point.

https://ourworldindata.org/grapher/electricity-prod-source-s...

I'm also not seeing your claimed Swedish impact in the data:

https://ourworldindata.org/grapher/electricity-prod-source-s...

Also worth bearing in mind that support payments generally are used to keep fossil plants open because they no longer burn enough fossil fuels to earn a profit from energy sales. It's an insurance policy which needn't ever burn any fuel to be worthwhile.

[AnthonyMouse]

> Germany's gas generation has indeed been flat while nuclear and coal is being phased out, so I guess you've very strongly proved my point.

That graph shows domestic generation falling by more than 100TWh and being replaced by "nothing" -- which is to say nothing shown on that graph, because now instead of generating and exporting electricity they're importing it:

https://ourworldindata.org/grapher/net-electricity-imports?t...

Primarily from France, which is using nuclear, hydro and natural gas (in that order).

[ZeroGravitas]

The net import in 2023 was only 10TWh so you've over explained this by x10, so something else must be going on than just importing nuclear from France (which is roughly 8TWh that year)

France is the biggest single source of imports but not the majority of imports since Germany imports from a range of countries and the energy mix of imports is roughly:

> the shares of RE, nuclear, and fossils in Germany net imports were 59%, 33%, and 8%, respectively.

https://www.renewable-ei.org/en/activities/column/REupdate/2...

Nice graph: https://www.renewable-ei.org/realfiles/pdfimage/1721291204_6...

And this makes sense as imports work on the merit order effect, with the cheapest going first. Why buy fossil electricity from one neighbour if another has cheap wind available.

[AnthonyMouse]

> The net import in 2023 was only 10TWh so you've over explained this by x10, so something else must be going on than just importing nuclear from France (which is roughly 8TWh that year)

They were previously exporting 90TWh.

> the shares of RE, nuclear, and fossils in Germany net imports were 59%, 33%, and 8%, respectively.

That's still a pretty big proportion of nuclear and fossil fuels, and it's not clear that the way they're calculating that actually works. Imports are going to be needed at times of high demand or low renewable output, when baseload capacity is being consumed for domestic use by the exporting country and incremental power for export has to come disproportionately from peaker plants, i.e. fossil fuels (or lower curtailment by nuclear in France).

Moreover, they're counting hydro under renewable, e.g. Norway is "99% renewable" but is in fact 88% hydro.

[ZeroGravitas]

The net import graph you linked to shows Germany hit record net exports in 2017, at 50TWh (roughly half the 90TWh level you claim) and at a time when nuclear and coal has been phased out by roughly triple that amount so, once again, the data does not line up with the claims being made.