In fast-transforming energy systems renewable technologies and innovative digital solutions play a major role to tackle the issue of climate change. Due to the increasing renewable capacities in energy systems, the need for flexibilities is emerging. Intelligent system management and increased utilization of flexibility are at the core of transitioning to a sustainable future energy system.
This thesis looks into the interplay between the need, potential and the value of flexibility in regional and decentralized electric power systems. It investigates the effects of different penetration levels of solar photovoltaics and wind power capacities within a regional system as more and more storage technologies are added.
An evaluation framework is created based on a systematic three-step-approach starting with (1) the evaluation of flexibility needs on a local level followed by (2) the identification of local flexibility solutions and (3) the economic assessment of the effects on local energy systems and end-users. The framework provides a generic process, applicable to regions with different demographics and thus bears the ability to be adjusted to any given region. This strategy shall close the gap between the nation-wide analysis of flexibilities and the household-specific approaches to further improve the overall functioning of an interconnected energy system with increasing bi-directional flows on the lower grid levels.
Bringing the data to the model, the framework suggests computing scenarios with the underlying demand profiles, the renewable energy generation data and integrates the techno-economic parameters for the flexibility options available in the region. Three different scenarios are being investigated – solar PV-dominated, wind power-dominated, and a mixed renewables (solar PV and wind) -dominated system. At the core of this evaluation, a calculation model was created to determine the differences between these scenarios regarding flexibility need, how this need can be met by storage technologies (Li-Ion batteries), and what the economics of these scenarios mean to the investors of flexible assets. The power grid is used only at times of local shortage or already fully utilized flexibilities in order to give priority to local optimization.
The results across all scenarios showed a weak economic performance. The investment costs of batteries have the strongest influence on the outcome across all considered factors. The results prove that there is potential to exploit for Li-Ion battery storages, but investments are unprofitable at current levels of capital expenditures, lacking suitable market conditions to leverage their potential e.g., in local flexibility markets. Solely increasing the capacity of renewables lead to an enormous volatile and unstable system where the need for grid infrastructure skyrockets. As a consequence, measures must be taken to cushion those effects. Storage technologies provide the possibility to stabilize the system, while providing additional features to elevate the value of flexibility.