REMix was developed at the DLR Institute of Engineering Thermodynamics and consists of the sub-models EnDAT and OptiMo (see Figure). EnDAT provides information on global renewable energy resources in high spatial and temporal resolution, assessed based on meteorological and geo-referenced data. It provides maximum installable capacities and hourly time series of renewable power generation, as well as power and heat demand. This information is the basis for the determination of least-cost energy supply systems in the linear optimization model REMix-OptiMo.
Across different sectors, the model covers a wide range of technologies for energy conversion, storage and transport. In the case of energy conversion, this includes not only the generation of electricity and heat from renewable and fossil sources but also the electricity-based production of synthetic fuels (hydrogen, methane, liquid hydrocarbons). For the temporal decoupling of generation and demand, the model includes electricity storage, heat storage, fuel storage, load management in households, trade and industry, as well as the controlled charging and grid feed-in of battery electric vehicles. In addition, energy transport between the model regions under consideration via the alternating current transmission grid, high-voltage direct current transmission lines and fuel pipelines is represented in the model in a simplified form.
REMix-OptiMo is programmed in a modular structure. Each technology is represented by an independent module representing its technical and economic characteristics. The model relies on a perfect foresight modelling approach and optimizes over the overall time horizon. Additional power plant, transmission line or storage capacity can be optimized by the model according to the available potentials and system requirements.
Taking into account constraints such as installed capacities or the flexibility of producers and consumers, REMixOptiMo simulates the interaction between all technologies in hourly resolution and determines the least-cost development and operation of the power system. REMix is designed to offer a high flexibility concerning geographical or technological focus. All modules can in principle be applied to regions of all sizes, ranging from world regions to single cities.