The real lesson about the end of nuclear in Germany

The end of baseload is coming

A lot of articles about the closure of the last German nuclear power plants have emphasized the cost in carbon emissions of closing nuclear plants rather than coal (more precisely: lignite) plants: see for instance Jean-Marc Jancovici, the highly publicized French pundit.

While I agree that Germany should have closed its lignite plants before its nuclear plants, the more important story here is that it has closed ‘reliable’ baseload plants and replaced them by “intermittent” renewables. And not on a small scale. Twenty years ago, baseload (nuclear+lignite) was 60% of total generation (roughly 30% each). Now it is about 20%. And most of that has been replaced by renewables - close to 30% of wind, close to 10% of solar, and some biomass (5-10%, which is similar to baseload).

In parallel, the share of flexible fossil fuel plants (gas and hard coal) has actually gone down - gas, while volatile, is still close to 10% of total generation like it was 20 years ago, and black coal has gone done from more than 20% to less than 10%.

(All numbers from Frauhofer - the same source as Jancovici. Solar is low in 2023 because there’s only been winter days in 2023 so far… Wind is higher for the same reason)

So more renewables and less baseload means less flexible generation!

Is that what you usually hear? That replacing nuclear (a lot of it) by (a lot of) renewables will actually reduce fossil fuel use in the power sector?

And yet it is the main lesson here. Lignite will be phased out in the next 10 years, and Germany will thus soon become a baseload-free system, dominated by renewables (which will then be well above 50% penetration, probably close to 60%).

And do you hear about how German is a larger exporter of power than France? And, even more significantly, that its exports are at a higher price than France’s (ie that they produce more at times that are better correlated to demand than France)? And that it is imports from Germany that allow France to go through peaks of high demand, because baseload cannot produce more than what it usually produces (that’s the whole point of baseload)?

Germany exports wind when it can, and flexible generation otherwise. Upward flexibility can only come from flexible plants that are switched off a lot of the time, and turned on only in times of need. So yes, Germany has a lot of gas-fired plants, and a lot of coal-fired plants, but they are actually used very little - only when demand (including from France) is very high and renewables supply is very low - which does happen, but not that often anymore. Fossil fuel power plants are relatively cheap (and made in Europe), and if they are used rarely they don’t emit a lot of carbon dioxide.

Germany had a horrible starting point in terms of carbon emissions of its power sector, but it’s improving that rapidly. France was lucky to have a largely decarbonated system to start with (the nuclear build up was smart in many ways, but low-carbon emissions was not amongst the reasons it was done originally) but now its emissions, while still low, are getting worse as the increasing unreliability of its ageing nuclear fleet requires increasing use of gas fired plants or imports (which are usually met, at times of peaks, by fossil fuels as well).

France was also lucky to have access to a massive battery - the Alps. Nuclear requires the huge volumes of storage/flexible capacity provided by large scale hydro, which France has plenty of, and borrows plenty more of from its neighbors. That capacity can, and will, be used differently once it no longer has to deal with the very large daily cycle of baseload (excess production at night is dumped in the Alps, and given to the system back the next day).

The future is not baseload, whether coal-fired or nuclear. The future is renewables and a mixture of smarter demand and flexible generation, whether hydro, new forms of storage, and a little bit of fossil fuel use (again, a lot of power plants does not equal to a lot of fossil fuels being burned - it makes sense to keep those plants available and use them only in case of extreme demand peaks compared to available supply).

Europe has paid a lot for early projects to make renewables cheap on a per MWh basis. Now, it is proving that it is possible to build a full system that is no longer dominated by baseload. That model will very soon prevail everywhere, because it’s cheaper and smarter. The only obstacles are permitting, and incumbents fighting tooth and nail to prevent it from happening. They will waste more years, but will be swept away.

And Europe, and in particular Germany, will have shown the way.