Grid Planning

How can energy grid infrastructures be designed and operated to ensure resilient, secure and cost-effective supply both today and in a future decarbonized energy system? 

The decarbonization of the energy system and structural transformation are changing supply and demand for electricity, gas and heat. The new system is characterized by distributed generators, storages and prosumers. Heat pumps, electrolyzer and cogeneration units are the link between sectors. Variety and scope of tasks in grid planning have increased considerably in recent years. The energy transition, new regulations, changing funding conditions, and the development of storage options and sector coupling are factors of uncertainty with regard to the need for grid expansion, both in terms of extent and temporal distribution. In addition, new equipment such as controllable local grid transformers or new requirements, for example due to e-mobility, lead to an enlarged solution space with increased complexity. Therefore, in the future, increasingly extensive planning tasks will have to be processed or existing plans will have to be adapted and revised. 

Experts at Fraunhofer Energy Research support the transformation of the energy grid infrastructure in various planning phases: From the initial potential study to the concrete target grid planning, during implementation in the pilot project and transfer to the real operation.

Competencies of the Fraunhofer Energy Alliance in the Field of Grid Planning

Asset Management: Grid Expansion, Grid Modification and Maintenance

The integration of volatile generators as well as the mobility and heat transition bring new multi-layered challenges not only for grid operation but also for grid expansion and grid modification. Just as important as operational asset management, which includes the integration of generating plants, additional consumers and maintenance of existing infrastructures, is strategic asset management in relation to grid expansion planning measures. The challenge for grid planners is both increased planning volume and an increase in complexity due to the additional technologies. Fraunhofer’s experts support customers along the entire process chain, from grid expansion planning and target grid planning, through the definition of supply tasks and optimized grid expansion, to evaluation tests. The competencies of the Fraunhofer institutes are not limited to the focused consideration of power grids, but also include (district) heating grids, charging infrastructure for electromobility as well as isolated and micro grids in a holistic view. The expansion and modification of gas networks also plays a special role on the road to climate neutrality. On the one hand, the decentralized feed-in of biogas must be facilitated, and on the other hand, the infrastructure for hydrogen supply must be made H2-ready in order to decarbonize both regional industry and the heat supply of households.



DiGO – Distribution Grid

Due to the German energy transition, the loads in the power grids are changing. Generating plants and additional consumers have to be integrated which increases the need for grid expansion planning measures.


ANaPlan - Autom. Grid Expansion Planning

In cooperation with partners, Fraunhofer IEE is researching how to implement cost-minimizing grid planning for distribution networks (more information German).


pandapower: Autom. Grid Planning

With the help of various tools, pandapower supports network planning systems in meeting quantitative and qualitative requirements.

Scenario Development of Future Supply Tasks

The energy transition—and especially sector coupling—present municipal utilities and local energy suppliers with strategic investment decisions regarding their future grid infrastructure for electricity, heating and gas. Until now, these decisions have often been made individually and separately by line of business. This can lead to bad investments which can be reflected in higher energy prices and thus be charged to the customers. Based on individual data, researchers at Fraunhofer create customer-specific scenarios for future supply tasks and develop optimal grid structures using innovative optimization tools. The scenario development of future supply tasks also focuses on cross-technology considerations with the aim of cross-sectoral infrastructure planning.




»SzenarienDB« aims to create a database for energy scenarios as an extension of the Open Energy Platform (OEP). Scenario data of several studies will be uploaded to the database to become accessible free of charge (more information in German).


Grid Study Hesse 2024 – 2034

Fraunhofer IEE is researching the effects of the energy transition on distribution grids in Hesse and drawing up recommendations for action (more information in German).



In the project »StraZNP – Strategic and Targeted Grid Planning« Fraunhofer ISE is developing a planning tool that calculates proposals for cost-optimal grid expansion for given and expected grid loads.

Grid Integration of Distributed Generation Plants, Storage Facilities and Consumers

In the future, electricity will be provided by a large number of decentralized generators. This poses a particular challenge for ensuring grid stability and security of supply. Decentralized supply concepts can help reduce grid losses by using as much of the locally generated electricity as possible where it is generated. The prerequisite for this is intelligent networking of generation plants, storage facilities and consumers. Experts at Fraunhofer Energy Research develop plant concepts for industry, commerce and municipalities based on renewable energy sources. The portfolio ranges from new combined heat and power concepts to hybrid local storage grids and function-bearing structural components for largely energy-autonomous buildings and settlements. The continuous development of innovative storage technologies, e.g. redox flow batteries and their grid integration, also plays an important role in the context of new plant concepts. With the development and implementation of energy management systems for hybrid systems, our experts also make an important contribution to the grid integration of decentralized generators.




Fraunhofer ISE is using simulation models to investigate the impact of the expansion of prosumers on the generation of electricity and the power grid in Germany.



Together with partners, Fraunhofer IEE examines and evaluates the integration and development of PV-self consumption models in the future energy system.


»Wind-powered Heating 2.0: Long-term Storage«

Together with partners, Fraunhofer IBP explores how surplus electricity from wind turbines can be used to cover the heating requirements of buildings (power-to-heat).



Together with partners, Fraunhofer IESE examines how the use of decentralized flexibility potentials (e.g., batteries of e-vehicles) can support the integration of electromobility (more information in German).



Together with partners, Fraunhofer IEE is investigating the coupling of the current power grid model with requirements and flexibilities from the energy sector. Cross-sector synergies for the energy system of the future are taken into account.

Grid Stability and Grid Recovery

In particular, the novel structure of the grid with decentralized generation plants, storage facilities and consumers can contribute to grid stability and compensate for voltage and frequency fluctuations on a small scale. Nevertheless, the ability to predict grid conditions is a core challenge of future grid management in the German power grid. The most important goal: To prevent bottlenecks in the grid before they occur. The institutes of Fraunhofer Energy Research support their customers with accurate forecasts regarding feed-in and consumption as a central element of optimized grid operation management. The overarching goal here is to create resilient grids and thus ensure security of supply. Resilience is defined as the ability of a system to maintain its functional capability under stress—at least to a limited extent—or to restore it within a short time. If a blackout does occur, the grid must be restarted. Until now, this was done by special central power plants. However, with a high number of decentralized generators, new concepts are needed. These already include the installation of systems such as batteries or cogeneration units in the grid planning, which can help to build up decentralized sub-grids.




»OVRTuere (Over Voltage Ride Through – Temporary Overvoltages and Derived Rules for Efficient and Safe Grid Operation)« investigates the technical causes of large-scale critical surges in the power grid.


GFM Benchmark

In the »GFM Benchmark« project, Fraunhofer ISE and its partners are developing an appropriate procedure to ensure grid stability and testing it with various grid-forming devices. 



To overcome challenges regarding the complexity of reactive power management across voltage levels, the system must be examined from the component to the grid management level (more information in German).


Verteilnetz 2030+

In the project »Safe and stable operation of inverter-dominated distribution grids - Verteilnetz 2030+« Fraunhofer IEE and partners are examining how  grid operation with a high share of renewable energies remains manageable (more information in German).