The modelling and simulation of power plant processes and synthesis processes for renewable energy sources are an essential factor in the expansion of renewable energy sources. The process efficiency and the profitability of planned plants must be quantified under variable conditions before recommendations regarding engineering and subsequent operation can be made. Simulation combined with technology monitoring can also be used to determine the potential for optimisation in regard to existing systems. To do this, ZSW uses the IPSEpro software (Integrated Process Simulation Environment). This software focuses on the simulation of detailed overall process chains, including the necessary peripheral systems, for example, the methane and hydrogen generation processes.