From surplus to opportunity: battery storage as a key factor in the energy transition Interview with Ilona Dickschas from TÜV Nord Clean Energy Solutions in the run-up to the Cross-Cluster Conference on 4.2.26 in Hamburg

Battery storage systems are the key to reliably integrating fluctuating solar and wind energy into the grid and reducing costs at the same time. They can provide balancing power in fractions of a second, prevent expensive grid overloads and enable intelligent self-consumption optimisation. However, regulatory hurdles, complex approval procedures and conflicts of interest are delaying their widespread introduction. In this interview, Ilona Dickschas from TÜV Nord Clean Energy Solutions explains what regional potential exists, how second-life batteries are rated and what role business continuity management (BCM) plays in the resilience of critical infrastructures.

Why is the development of battery storage systems an integral part of a sustainable energy transition?

Due to the increased expansion of renewable energies, our power grid is subject to ever greater and more diverse fluctuations – be it hourly, daily or seasonally. Since wind and solar energy are, by their nature, not permanently available, a flexible balancing strategy is required. Renewable sources were already responsible for 62% of net electricity generation in 2025 and this percentage will continue to increase in the coming years. Battery storage systems offer a crucial solution here: they make it possible to shift surplus electricity generated during the day, for example, to times of higher consumption – such as in the evening hours. In doing so, they not only make an important contribution to grid stability, but also increase profitability by optimising self-consumption. This allows renewable energy sources to be used more efficiently, and dependence on conventional power plants can be further reduced.

What can these storage systems do both in terms of (regional) grid stabilisation and cost reduction in our grids? What compromises have to be made with the grid operators for this, what market-based incentives are needed?

Battery storage systems are able to draw or feed electricity from/into the grid within seconds and thus play a central role in the provision of balancing power. While this task used to be the realm of pumped storage power plants, large-scale battery storage systems are now increasingly taking on this function and receiving remuneration for doing so. Battery storage systems also enable co-location, meaning that the output of solar and wind power plants does not have to be curtailed when the grid reaches its capacity limits. This way, the renewable energy generated can be used efficiently and grid overloads can be avoided. For successful implementation, it is essential to initiate dialogue with the grid operator at an early stage in the planning phase of a battery storage system so that both grid-serving and market-serving aspects can be coordinated and taken into account optimally.

Are there currently any regulatory hurdles to fully exploiting the potential of battery storage systems? Are there any conflicts of interest?

Yes, there are currently a number of regulatory hurdles that make it much more difficult for both investors and project developers to realise battery storage projects. The challenges range from complex and lengthy approval procedures to the legal classification of battery storage systems as separate generators and consumers, to the lack of a uniform and clear legal framework. These ambiguities cause time-consuming planning processes and significantly slow down the implementation of urgently needed storage projects. In practice, this is often particularly evident in grid connection: procedures, requirements and available connection capacities are sometimes complex and time-consuming.

Conflicts of interest arise at various levels, as numerous stakeholders such as municipalities, grid operators, project developers, investors and plant operators are all involved. This makes it all the more important to initiate an open and transparent dialogue between all participants at an early stage. This is the only way to clear up misunderstandings, break down prejudices and jointly develop viable solutions for the use of battery storage systems.

In which regions are the projects implemented and where does integration make the most sense locally?

Large-scale battery storage projects are currently operated, being implemented or are at the planning stage in all federal states. Locally, integration makes particular sense where storage systems provide a concrete benefit to the grid and system – for example, in regions with high feed-in from wind and photovoltaic plants (to reduce curtailment) as well as at grid-relevant nodes such as substations or in bottleneck areas of the distribution and transmission grids. It is exciting that more and more battery storage systems with a capacity of over 50 MW were installed last year and the first 100MW projects also went into operation. There is also an evident trend for storage time being extended from the one-hour systems we have seen up to now to two-hour systems.

Due to the continuing decrease in costs for large-scale battery storage systems, it is now much more attractive to rely on new systems. Increasing standardisation and the use of container-based solutions lead are leading to constant further cost reductions and enable the efficient, economical integration of modern storage technologies.

On the technology used: is it still attractive for operators to use second-life car batteries?

Due to the continuing decrease in costs for large-scale battery storage systems, it is now much more attractive to rely on new systems. Increasing standardisation and the use of container-based solutions lead are leading to constant further cost reductions and enable the efficient, economical integration of modern storage technologies.

Keyword BCM (business continuity management): against the backdrop of a world marked by crises and conflicts, securing critical infrastructures is becoming increasingly important. What aspects do you consider in BCM and how do you support the operators of energy infrastructures?

These days, when we talk about business continuity management in the energy sector, it goes far beyond the classic risk analyses. We see that energy infrastructures are increasingly becoming the target of hybrid attacks. One very recent example is the Berlin power outage at the beginning of 2026, which paralysed several districts for days and left over 45,000 households without electricity, without heating, and in part with severely limited mobile phone reception. For us in the field of BCM, this sort of event means that we have to look at physical, digital, operational and systemic risks in equal measure. This is exactly what is shown by the Fraunhofer IEE analysis, which emphasises that resilience in the energy system goes far beyond technical defects and also includes sabotage, cascade effects or digital attacks. Our support for infrastructure operators therefore always begins with a structured systematic analysis: which components are critical, which dependencies exist, which failures would have cascade effects? We then develop redundancy and restart concepts – very specifically, from an emergency power supply and spare-parts strategies to communication security in a blackout scenario. Because the Berlin case has shown:

When mobile communications and the Internet are impaired, even the coordination of the helpers becomes a challenge.

It is important to note that merely drawing up plans is not enough. These must be practiced regularly. We regularly train emergency scenarios and restarts with crisis teams. It turns out that it is usually the details that matter. Details such as fuel logistics, operational personnel for power units or the supply of critical facilities make the difference between success or failure – companies that have practiced scenarios like this beforehand come through the situation much better.

Are centralised or decentralised energy supply systems easier to protect in terms of security and reliability? (Would you say there any interesting aspects that the Berlin power outage has provided as learnings for a BCM)?

That’s an interesting question, and the answer lies in a balanced mix. Central energy supply systems are generally easier to monitor because the sites are fewer in number, while operated highly professionally. The problem, however, is their susceptibility to so-called single points of failure, i.e. critical individual components whose failure can affect large parts of the supply. The Berlin blackout has shown this to great effect: a single attack on a cable bridge disconnected around 45,000 households and over 2,200 commercial enterprises from the grid – and in the middle of winter for that matter. Repairs took days, and the complete restoration even weeks or months. This makes it clear how vulnerable central nodes can be. Decentralised systems, on the other hand – for example, photovoltaics with battery storage, microgrids or stand-alone grids – noticeably increase resilience. At the same time, however, decentralisation also brings challenges, for example in IT security, standardisation or operator qualification. The most important lesson from Berlin is, therefore, that we need both. A robust central grid – but supplemented by decentralised, resilient stand-alone networks that can continue to run autonomously in crises. This includes technical measures such as closed loop lines or additional transformers, but also organisational resilience: clear crisis communication, secured emergency power capacities and experienced crisis teams.

In short, centralised systems are easier to protect, but structures that are more decentralised make the overall system more resilient. And the Berlin power outage has made it clear to us that we need to switch from pure protective logic to real resilience logic.