Tennet proposes new grid connection rules

25.08.2025

Source: E & M powernews

The transmission system operator Tennet is calling for reforms to the rules for grid access. A position paper is to show which levers need to be used.

Storage systems offer great potential for making generation and consumption more flexible. They are considered a key success factor for the integration of renewable energies into the electricity grid and for its stabilization. Now that more and more large-scale storage projects are being planned and are requesting a grid connection, grid operators are sounding the alarm.

"The enormous rush for grid connections - especially from battery storage systems - shows that the current rules no longer fit the reality of the energy market," says Tim Meyerjürgens. The CEO of transmission system operator Tennet paints a bleak scenario. Without reforms, access to the electricity grid threatens to become a bottleneck.

This is because not only storage facilities, but also system-relevant power plants, data centers and industry need direct access to the grid. In view of the veritable rush for grid connection capacities, new connection procedures, smart solutions for resource utilization and more flexibility in the planning and expansion of substations as central hubs are urgently needed, according to Meyerjürgens. Otherwise, negative consequences for security of supply and the business location are to be expected.

Tennet therefore presents a series of proposals in a position paper in order to - as the title of the five-page paper says - provide "Political impetus for the further development of the grid connection process".

It must be possible to prioritize certain customer groups for grid connections. New controllable power plants, grid-serving loads or grid-serving storage systems are examples of this. A new grid connection procedure must be established in the near future that allows an economically sensible, balanced and efficient allocation of limited resources. However, this requires transparent criteria so that the transmission system operator can deviate from the first-come, first-served principle and "differentiate without discrimination", write the authors of the paper.

Prioritization of storage systems

According to Tennet, short-term solutions must be created for battery storage systems - at least if not all customer groups can benefit from a new regulation. This is where the transmission system operator sees the greatest need for action. Tennet points out that the ordinance regulating the grid connection of systems for the generation of electrical energy (KraftNAV), which is used for battery storage systems in the grid connection procedure, was originally designed as an individual process for power plants. At that time in 2007, the legislator had assumed around ten power plants per year for all control areas as a whole.

In addition, a continuation of the grid fee exemption for battery storage systems beyond 2029 should "urgently be linked to grid serviceability criteria, for example via flexible grid connection contracts". An "unconditional grid fee exemption" is no longer in keeping with the times. To get an idea of what such a regulation could look like, Tennet recommends taking a look at the Netherlands, where grid customers receive a 45 percent discount on grid fees if they allow restrictions to be placed on power consumption for 15 percent of all hours. The transmission system operator is also calling for the mandatory introduction of flexible grid connection contracts. This would enable better utilization of grid connections.

Another proposal relates to securing and protecting areas around substations under planning law. This would allow grid operators to expand quickly if necessary.

In addition, grid operators should be allowed to provide additional switchgear panels when building new substations or expanding existing ones, above and beyond what is currently considered "demand-based". A differentiation of the construction cost subsidy according to customer groups should provide an incentive for an even distribution of storage facilities in the south of Germany and electricity-intensive customers in the north.

Finally, Tennet advocates greater promotion of the multiple use of grid connection points and the introduction of cross-grid connection planning at regional level. "It is important that all political levels - from the municipal administration to the EU Commission - work together to find solutions to this challenge," emphasizes Meyerjürgens.

The position paper entitled "Political impetus for the further development of the grid connection process" is available on Tennet's website.

Author: Fritz Wilhelm