Alexandra Kaatz studied electrical engineering and information technology with a focus on energy technology at TU Dortmund University and completed her Master of Science. Since joining the Federal Network Agency, she has worked in energy regulation with a focus on grid development and system stability in the transmission grid. After a year in the Grid Expansion Department, she has been Head of the Offshore and International Team for almost five years and recently took over as Deputy Head of the Scenario Framework Team. Her department is responsible for the entire grid development process, from the consultation and approval of the scenario framework to the review of grid expansion measures.
1 Dear Ms. Kaatz, thank you for giving us an insight into your day-to-day work today! Grid expansion is one of the most complex technical challenges of the energy transition. What central role does the expansion of the transmission grid play in this context and what technical and regulatory hurdles need to be overcome in order to provide the necessary grid capacities to integrate renewable generation as quickly as possible?
Grid expansion is a fundamental component of the energy transition. Grid expansion at distribution grid level serves in particular to integrate smaller regional producers and new local consumers, such as heat pumps. Transmission grid expansion, on the other hand, is necessary for the large-scale transportation of higher outputs. The expansion of large wind farms is taking place in the north and north-east of Germany in particular. The capacity of offshore wind farms is to be expanded to 70 GW by 2045. Large consumption centers, on the other hand, are located in the south and west of Germany. In order to bring the energy to these consumers, the expansion of the transmission grids is absolutely essential.
In the past, there have been lengthy approval processes, which have often been further complicated by massive resistance from the local population or municipalities. In order to explain the background and the need for grid expansion to the public, both the transmission system operators (TSOs) and the Federal Network Agency have held extensive participation and information events. The amendment to the NABEG and the EnWG and the associated introduction of preference areas will also significantly shorten the approval processes for direct current projects, which will speed up grid expansion
2. the grid development plan (NDP) is the result of extensive consultations with various stakeholders. What particular challenges do you see in balancing the interests of grid operators, political objectives and the requirements of the industry? How do you manage to incorporate these different perspectives into the scenario framework and long-term grid development?
It is very important for the Federal Network Agency to involve the individual stakeholders in the NDP process. In order to ensure robust planning of the grid expansion, the process is repeated every two years so that any legal or technical changes can be reviewed and, if necessary, reflected in the infrastructure planning. First, the TSOs prepare a draft scenario framework (SZR), on which the Federal Network Agency then consults the public. During the consultation, we will also hold information events and invite all stakeholders to participate. In order to meet the future requirements of sector coupling and to enable greater integration of the grid planning processes, the TSOs have launched a joint market survey with the transmission system operators (gas) for large consumers. This joint survey took place for the first time in the current process and is now to be carried out on a permanent basis in order to be able to map the future needs of the industry even better.
3. market modeling and grid calculations are essential tools for ensuring system stability. How exactly do these modeled scenarios and the grid calculations based on them help to identify bottlenecks in the electricity grid at an early stage and efficiently determine the actual need for grid expansion?
In order to make our electricity grids fit for the future, three different scenario paths are being developed for the target years 2037 and 2045. These scenarios form the basis for the subsequent regionalization, market modelling and the grid calculation based on them. Based on a historical weather year, time series are first created for the feed-in of renewable energies and for consumption. This means that generation and consumption are calculated for each of the 8760 hours of a year. The consumption that cannot be covered by renewables in the individual hours is referred to as the residual load. This must be covered by the use of storage, flexibility, controllable power plants or imports. If the generation is higher than the consumption of the individual hour, the residual load becomes negative. This surplus generation is then generally used by storage facilities or electrolysers or exported. The result of this market modeling forms the basis for the grid calculation. The resulting utilization of the grid in the individual hours ultimately shows the need for necessary grid expansion.
Without these complex steps of creating the scenarios, locating consumption and generation in the regionalization, market modelling and grid calculation, a serious determination of future grid expansion requirements would not be possible.
4. flexibility is a decisive factor in the future electricity system. Which technological options do you see as particularly suitable for minimizing the need to expand the grid? Which technologies could be implemented in the short term and make economic sense?
Private households as well as industry and commerce can and must make their contribution in the future. For private individuals, the potential is increasing in particular with new applications such as electromobility and heat pumps, but the combination of PV systems and small battery storage systems can also make a major contribution. At present, however, storage systems are generally used by private individuals to optimize their own consumption, which means that their potential is not fully exploited. In addition, the ability to react to price signals and control the devices accordingly is a basic requirement. This requires a rapid expansion of smart meters and the creation of flexible electricity tariffs. The current penetration of smart meters is only around 1%. Although the choice of flexible electricity tariffs has increased slightly in recent years, it is still very limited.
In the past, technical conditions and the structure of grid fees have generally led to rigid consumer behavior in terms of industrial demand. However, individual sectors are quite capable of reacting flexibly to price signals. This flexibility is also known as load management or demand side management (DSM). By adjusting demand behavior, it is possible both to reduce one's own electricity costs and to relieve the overall system. In the draft SDR, the TSOs propose a DSM potential of 5.3 GW to 6.7 GW in 2045.
A combination of industrial consumption with in-house storage to increase flexibility is also likely in the future.
5 The Federal Network Agency is currently revising the electricity grid fees, particularly for electricity-intensive industrial customers, with a focus on greater flexibility. If you could make a wish for the future design of electricity grid fees: What changes or measures would you like to see?
I would like to see a fair and fair distribution of grid fees. Of course, our industry should not be excessively burdened either. In my opinion, this is a matter for politicians to remedy.
