“Higher network utilization without putting security of supply at risk”
The electricity transmission grid operator TransnetBW is building a “grid booster” with a power output of 250 megawatts in Kupferzell in the German state of Baden-Württemberg at a cost of 200 million euros. The grid booster will act as a safety buffer to protect the transmission network by making energy available from its lithium-ion batteries within seconds behind the bottleneck created by a congested line. Grid boosters are a partial replacement for preventive measures such as the low utilization of network capacity and redispatching. In this interview, Severin Mosek, the head of the grid booster project at TransnetBW GmbH, explains the idea behind the facility and its benefits for consumers.
What role does the grid booster in Kupferzell play?
The purpose of the grid booster is to increase the load on the existing electricity grid without putting security of supply at risk.
Severin Mosek, the head of the grid booster project at TransnetBW GmbH
Can it also handle longer supply bottlenecks?
The grid booster is not designed to maintain the energy supply over a longer period. Instead, it will allow the existing transmission grid to operate under a higher load, even in a passive state.
How does it work?
In a normal situation, the integrated battery system is fully charged. This allows for higher utilization of the transmission grid. If a circuit in the grid fails, this would usually result in the remaining circuits becoming congested. In this case, the grid stabilization system functions as a kind of airbag. Within seconds, we can supply energy to the grid at a strategically important point. At the same time, the generation in the north will be reduced, which enables the circuits to remain within their thermal limits. And while the grid booster is supplying energy, we have the time to manage the bottleneck, either by switching circuits or firing up power stations.
Why are facilities of this kind needed throughout Germany?
Intelligent management and networking can reduce the load on the electricity grid right across the country. This is why it is a good idea to have grid boosters all over Germany.
How many grid boosters would be required in total in Germany and in Baden-Württemberg?
We need to understand exactly where the bottlenecks occur in order to put the grid boosters in the right places. It is not so much about how many there are but more about whether they are in the best possible location, for example the very heavily congested node in Kupferzell.
What are the benefits for consumers?
The grid booster will reduce costs in two areas: the expansion of the grid and redispatching. We all pay for both of these things via the grid charges on our electricity bills. In order to minimize the risk of overloads, as a precautionary measure the capacity of the power lines is not fully utilized. A grid booster allows the use of capacity to be increased, which means that fewer new lines are needed. Grid boosters also reduce the need for redispatching. This is a measure which transmission grid operators use to resolve bottlenecks. It involves reducing the power supply before the bottleneck and increasing the power supply after it. This results in significant costs being incurred in the form of compensation for the energy that was not used and payment for the additional energy.
What is the current status of the grid booster project?
The documents needed for planning approval are currently being inspected for completeness by the regional council in Stuttgart. The next step is the public consultation. After planning approval is granted, the construction work can start. This will be followed by testing and finally full operation, probably in 2026.
