The Act on the Reduction and Termination of Coal-fired Power Generation (KVBG - Coal-fired Power Generation Termination Act) came into force on August 14, 2020. It sets out regulations for ending coal and lignite-fired power generation in Germany by 2038 at the latest. The ability of the transmission system operators (TSOs) to fulfill their legal obligation under Section 11 of the Energy Industry Act (EnWG) to ensure the security and reliability of the electricity supply system at all times is of particular importance to the success of the gradual reduction of coal-fired power generation.
You can therefore find the study papers on the accelerated coal phase-out by 2030 from the four transmission system operators here.