The cellular approach (CA) is a novel planning, operational, and market principle tailored to address the specific technological and economic challenges arising from the extensive transformation of our energy systems. Current principles will likely not be adequate for the future energy systems with high share of renewable energies, new loads, and strong dispersion over all grid levels. In the CA, the energy system is divided into hierarchically ordered, cross-sectoral energy cells (EC). ECs optimize their own technology portfolio considering subordinate ECs with the aim to benefit the overall system whilst keeping the cost of energy low. To achieve this, ECs are embedded into a new market harmonized with the management concepts of the ECs enabling an optimization based on economic parameters. Verification of such a system concept requires an extensive simulation model capable to represent the energy system on all hierarchical levels and over a wide geographical area. This paper provides an overview of the system structure of a cellular energy system, the according market concepts, and the simulation model used for the analysis of the system concept.