Economists of the German Institute for Economic Research (DIW) conclude in a recent paper that “the decline in nuclear power will temporarily lead to a higher use of fossil energies and imports, which will increase CO2 emissions in the short term. However, these should be quickly reduced by the accelerated expansion of renewable energies.”
-- https://www.cleanenergywire.org/news/qa-why-germany-phasing-out-nuclear-power-and-why-now#six
Temporarily they say...