Your assertion that the uptick in coal in recent years is purely a result of the country’s shutting down of nuclear is dubious. Yes, most of the increase in coal use can probably be attributed to the decline in nuclear, but there has also been an increase in coal due to more intermittent wind and solar on the grid. Germany’s energy policy gives wind and solar generation first priority access to the grid. Large influxes of wind and solar typically force natural gas generation, not coal generation, offline due to gas’s higher marginal cost. Grid operators have filled the gap by building more coal capacity or burning more coal in existing plants. So the picture is not as simple as you make out and wind has not led to a one-to-one displacement of CO2 as you imply.
That said, we’re not arguing against wind or that wind has driven an increase in CO2 emissions. Wind and solar have clearly displaced some carbon emissions and Germany would be more carbon intensive if wind and solar hadn’t increased over the same period that nuclear has been declining. What we argue in our piece, and what I think is more important than arguing about how much carbon wind has displaced, is that by rejecting nuclear Germany has locked itself into an electricity sector that will be no cleaner in 2020 than it was in the year 2000.
At the planned current rate of expansion, when the last German nuclear plants shut down in 2022, renewables will be generating about 38 percent of electricity. With no more nuclear power in operation this will be the total share of zero-carbon electricity, but that’s almost exactly the same share of zero-carbon electricity Germany produced in 2010, when its share was 38.8 percent (22.4 percent nuclear and 16.4 percent renewable). This has been dubbed Germany’s lost decade.
But it’s more like a lost generation given that the policy of favoring renewables over nuclear has been in effect for 13 years and counting. In 1999, a peak year of power generation for nuclear, the share of zero-carbon electricity was 36 percent, with nuclear contributing 31 percent. Thus, over a twenty-three-year period of expanding renewables and closing nuclear plants from 1999 to 2022, Germany will have managed to decarbonize a meager 2 additional percentage points of its electricity.
And while I appreciate you pointing out that the countries with the most aggressive wind deployment have seen emissions reductions (you would need to do more analysis to prove causation here, rather than correlation), the countries that have experienced the fastest rates of decarbonization of the electricity supply are those that have rapidly ramped up nuclear power. For instance, between 1971 and 2006, France and Sweden, which both pursued nuclear power aggressively, achieved the fastest average rates of decarbonization of energy supply of any OECD nations (-2.0% and -2.5%, respectively – see link below). So while wind definitely contributes to modest decarbonization and CO2 emissions reductions in most cases, by locking out nuclear Germany has removed from the table the technology that has the best track record of meeting climate goals.