Smart Charging for Greater Grid Stability: OctoFlexBW Project Demonstrates Potential for Redispatch
Stuttgart (Germany) - Redispatch ensures the stability of power grids, but is becoming more complex with the growing share of electricity generated from renewable energy sources. A pilot project now shows how electric vehicles can be actively integrated as flexible consumers to efficiently support congestion management.
Redispatch in transition: flexibility becomes a key factor
Redispatch is a central instrument for ensuring grid stability. Power plants are specifically controlled to balance grid bottlenecks. As the share of renewable energy increases, this measure is becoming more important - while at the same time the need for flexible solutions is growing.
With advancing electrification, particularly in the transport sector, new potential is emerging through additional flexibility in the electricity system. In 2025, new registrations of electric vehicles rose by 43.2%, with their market share reaching 19.1%. This creates a growing number of decentralized battery storage units that could be used for redispatch measures.
So far, redispatch has largely been implemented by conventional power plants. The integration of electric vehicles now offers the possibility to expand this measure with a decentralized, market-oriented component and to make targeted use of existing flexibility.
OctoFlexBW: electric vehicles as a solution for Redispatch 3.0
The OctoFlexBW pilot project by Transnet BW and Octopus Energy clearly demonstrates how electric vehicles can be integrated into redispatch processes. The aim was to fully map all technical and energy industry processes - from controlling the wallbox to system operation by the transmission system operator.
In the project, more than 700 electric vehicles from private households were aggregated. They provided around 2 MWh of flexibility per day. Extrapolated to one million vehicles, this results in a potential of about 3 GWh per day. Annually, up to 0.5 TWh could contribute to grid stabilization, covering a significant share of redispatch demand.
Dr. Oliver Strangfeld from Transnet BW explains: “With the integration of electric vehicles from private households, Transnet BW and Octopus Energy have impressively demonstrated that the market-based solution we are pursuing for grid congestion management works flawlessly and is ready for market ramp-up.”
Project implementation: flexible and convenient use of electric vehicles
Octopus Energy scheduled charging processes so that vehicles were fully charged in the morning and charged as cost-effectively as possible. Using the KrakenFlex IT platform, the flexibility potential of the vehicles was determined and the aggregated data was transmitted to the Transnet BW DA/RE platform. In the event of anticipated grid bottlenecks, DA/RE issued a dispatch signal, which KrakenFlex automatically translated into an adjusted charging strategy and coordinated the vehicles - without compromising user comfort. The system used each vehicle’s available charging window - the period during which the car is connected to the grid - to optimally control charging.
Vehicle owners could still individually specify when their car needed to be fully charged and at the same time benefited from lower electricity costs through the “Intelligent Octopus” tariff. Feedback from the project showed high acceptance and willingness to provide flexibility to support the grid.
The approach is also economically attractive: “Consumers can actively contribute their flexibility while saving costs. Either consumers pay for expensive redispatch, or they provide their flexibility and get paid,” said Bastian Gierull, CEO of Octopus Energy in Germany.
Outlook: from pilot project to market-based application
From Transnet BW’s perspective, the results of OctoFlexBW show that electric vehicles are a practical addition to the existing redispatch system. They can help manage grid bottlenecks more efficiently while establishing new market mechanisms.
The follow-up project “DataFleX” aims to scale this approach further - with more than 1,000 vehicles and the integration of additional flexibilities such as home battery storage. In the future, heat pumps could also be integrated. A suitable regulatory framework is now crucial for widespread implementation. Only with regulatory support can electric vehicles fully realize their potential for the overall system, reduce grid fees, and actively contribute to the stability and efficiency of the electricity system.
Source: IWR Online, 27 Mar 2026
