Is the coherence of coal phase-out and electrolytic hydrogen production the golden path to effective decarbonisation?

• Scenario-based simulations with EnergyPLAN based on Choice Awareness Theory. • Evaluation of recent coal power phase-out plans on annual and hourly bases. • Decarbonising effects of the coal phase-out and electrolytic hydrogen production. • Analysing the coherence of phase-out policies and low carbon technology diffusion. We analyse whether Germany will fall short of the country's decarbonisation targets. Bearing this potential failure in mind, the present study investigates technological options and their effectiveness for decarbonising the energy system from a systemic perspective. We consider the country's coal phase-out, the increasing amounts of electricity from renewable energy sources, more efficient heating concepts as well as the evolving of smart charging infrastructures and large-scale storage options. Based on the declared plans of the federal authorities and alternative proposals of environmental associations, ten distinct decarbonisation scenarios for the period from 2020 to 2030 form the basis of our models. Using the Energy PLAN simulation tool, annual and hourly performance indicators were computed in order to evaluate the effectiveness of decarbonisation measures. In particular, we examine the increasing usage of electrolysers for both the absorption of excess electricity and the production of hydrogen as a substitute for fossil fuels in relation to the timing of the coal phase-out. Pursuing this approach, we demonstrate the coherence between coal phase-out policies and low carbon technology diffusion. Our findings reveal that implementing the coal phase-out earlier than has been scheduled by the country's Commission on Growth, Structural Change and Employment mitigates the non-achievement of the decarbonisation targets. Moreover, our results suggest the upscaling of domestic electrolyser capacity to up to 9554 MW by 2030. [ABSTRACT FROM AUTHOR]