The 2026 Grid Package does allow new PV and battery storage projects to connect to the grid even in bottleneck areas, but it links this to the controversial redispatch reservation. The strategic Network overlay offers a solution and is increasingly coming into focus. It uses existing capacities more efficiently, reduces curtailment risks, and, according to an EWI study, saves up to 1.8 billion euros in grid expansion costs annually.
Targeted grid overlay has been enshrined in Section 8 of the EEG since February 2025, thus allowing the realization of renewable energy projects even in „capacity-limited grid areas,“ as they are characterized in the Network Package 2026 be named. This involves the Capacity limit a mains connection consciously through large solar parks and/or large-scale battery storage built over. Intelligent grid management specifically absorbs feed-in peaks and shifts them to times of lower grid load. This significantly reduces curtailments caused by redispatching, while simultaneously unlocking new revenue potential – for example, through flexible marketing or grid-friendly operation.
The redispatch clause and its risks for large-scale PV projects
In congestion areas (curtailment >3% of annual consumption), new renewable energy plants will be required to install, in accordance with Grid Package 2026, a Redispatch reservation accept. This means that in the event of grid-related curtailment, the EEG compensation will be completely suspended for up to 10 years. This, in particular, limits the economic viability of Large-scale PV projects especially one, as future redispatch quotas are difficult to predict. Investors are therefore also calculating more conservatively, and financial institutions have since been pricing in bottlenecks and congestion projects at a higher rate.
Against this backdrop, Flexibility solutions directly at the grid connection point (GCP) increasingly becoming a prerequisite for the feasibility of new projects. Through the integration of storage and the use of intelligent control systems, feed-in peaks can be specifically smoothed out and grid-related curtailments actively avoided. Instead of passively accepting redispatch measures, operators can flexibly adapt their plants to the grid situation and thus stabilize the actual feed-in volume. This not only increases planning certainty but also improves bankability, as projects become more resilient to the economic risks of redispatch reservations.
What is grid overlay - and how does it work with PV + BESS?
Grid overlay describes the principle of consciously oversizing the installed capacity of a PV system beyond the available grid connection capacity. Specifically, this means, for example: A 15 MWp photovoltaic system is being done together with a BESS with 5 MWh capacity to an NVP with only 10 MW connected load connected. Technically, the smart control system balances the difference between generation and grid capacity. While the solar system generates high feed-in peaks—especially around noon—the battery storage system absorbs excess energy and feeds it back into the grid at a later time—such as in the evening or when solar radiation is lower. Only as a last resort is it necessary to curtail feed-in.
This allows for the smoothing out of negative or positive load peaks in the grid and enables grid capacity to be utilized much more efficiently. A 2024 study by the BEE shows that even with a development density of around 150 %, curtailment losses remain at a low level of less than 5 %, while the utilization of the grid connection point increases by 30 to 40 %. With integrated storage systems, penetration rates of up to 250 % are even achievable in practice. Overall, the Network usage through network overlay improve by 53 %.
EWI Study: 1.8 Billion Euros in Grid Expansion Cost Savings
An EWI study from summer 2025 quantifies the potential of the BEE study and provides specific figures. According to the study, overlaying the grid with PV and wind power reduces annual grid expansion costs. by up to 1.8 billion euros. Furthermore, the optimized utilization of existing infrastructure provides a much-needed delay for costly new construction. For large-scale PV projects combined with BESS, this means: The Network bottlenecks become opportunities, as the resulting local flexibility reduces the need for grid expansion in the region.
Combined with cable pooling – meaning PV, wind, and BESS at the same NVP – a multiplier effect is created. Surplus solar power charges batteries during the day, which feed into the grid when needed or cushion redispatch situations. This increases the grid utilization rate and reduces costly curtailments. According to EWI, the following savings arise from grid overbuilding:
| Superstructure | Network utilization | Loss of regulation | Cost savings |
| 100 % | Basis | tall | none |
| 150 % | + 30-40 % | < 5 % | tall |
| 250 % | + 50-53 % | 10-15 % | up to €1.8 billion/year |
Practical examples of meaningful network overlay
1. Open-space PV system with BESS in a capacity-constrained distribution network area
A distribution system operator classifies a grid area as a „capacity-constrained grid area“ because the curtailment rate there is already above 3%. A project developer is planning a new solar farm and is informed by the grid operator that at the desired grid connection point, only 10 MW connected load be available. A classic project with 10 MWp PV and redispatch reservation would fundamentally be connectable, but would bear the full economic risk of uncompensated curtailments.
Instead, the operator opts for strategic network overlay: installing 15 MWp of PV capacity and supplements the system with a BESS with 7.5 MWh capacity. Over a Energy management system (EMS) It is ensured that the maximum feed-in power at the NVP of 10 MW is not exceeded at any time.
In times of high solar radiation, surpluses are routed to the storage system instead of being curtailed. Only when the storage system is full and the grid load does not allow for additional feeding does a controlled power limitation of the PV system take effect. On an annual basis, the operator can thus achieve a significantly higher energy yield via the same grid connection, while redispatch measures are noticeably reduced.
2. Hybrid project with wind farm, PV system, and BESS
In a windy region, a wind farm with 20 MW connected load has been in operation for several years now. Although the NVP is operating at 100% capacity and power curtailments occur regularly, and although an expansion would be costly and feasible only with a substantial construction subsidy, the operator is interested in integrating additional photovoltaic capacity and a large-scale storage system.
As part of a hybrid concept, the existing grid connection capacity is deliberately overlaid: in addition to the wind farm 15 MWp of PV capacity and one 10 MWh battery energy storage It is connected to the NVP. Here too, the EMS automatically adapts to the overall system. During the night and with weak solar radiation, wind energy dominates the feed-in, while the solar park delivers high outputs during the day. The storage system absorbs wind and PV surpluses during times of low grid absorbency and makes them available again with a time delay. This smooths out the feed-in peaks of the combined system and significantly reduces redispatch interventions.
3. Large consumers with PV feed-in and BESS
An energy-intensive company has a medium-voltage connection with 5 MW power, through which all electricity purchases and a portion of the existing rooftop PV system are managed. Due to rising electricity prices and sustainability goals, the company plans to significantly expand its self-generation capacity with a ground-mounted PV system and a BESS on its premises. However, the grid operator has indicated that increasing the connected load would only be possible with a significant expansion of the grid.
The company decides to strategically overbuild the existing network connection and additionally installs 7 MWp of PV capacity with BESS with 4 MWh capacity. In normal operation, the photovoltaic system first covers the plant's own consumption. The battery storage is charged with the surplus, and if connection capacities are available, the operator receives feed-in tariffs. During operating times with low consumption or on weekends with high PV generation and a full battery, the EMS prevents the 5 MW limit from being exceeded and throttles back the PV system.
Cable Pooling as Operational Implementation of Network Overlay
Die beschriebenen Szenarien setzen in der Praxis Cable Pooling ahead – the shared use of a network connection point by PV, BESS, and potentially other renewable energy systems. There are two main variants:
- Co-locationModel: The PV system and BESS have separate market locations (MaLo) and metering concepts. The storage system can flexibly charge using off-grid electricity and participate in balancing energy markets, while the PV system remains eligible for EEG subsidies.
- Hybrid modelPV system and BESS are connected behind a MaLo. The storage system exclusively charges with green PV power – compliant with the EEG, but with lower market flexibility.
Both models utilize flexible grid connection agreements (§ 8a EEG), which define dynamic feed-in limits. An EMS coordinates all real-time decisions between battery charging, self-consumption, and grid feed-in.
Legal and Technical Requirements
Legal Projects needed:
- Approval from the grid operator for construction (Section 8(1a) of the EEG 2023)
- Flexible grid connection agreement with defined maximum power levels
- Separate metering concepts for co-location (metering point + meter)
- Demonstration of technical controllability
Technical The following are crucial:
- EMS with predictive models (PV yield, load, grid prices)
- Fast power control (< 1 second response time)
- Communication with grid operator (e.g. via IEC 61850)
- Redundant systems for operational safety
Checklist for the Implementation of Network Overlay Projects
CUBE CONCEPTS takes on the holistic coordination of all critical steps in planning and implementing grid overlay projects. The starting point is a sound network analysis, evaluating curtailment rates and capacity limits at the grid interconnection point. Based on this, we develop an optimized technical concept with the appropriate degree of overlay, battery storage, and EMS.
In parallel, we are clarifying the regulatory framework, particularly the flexible grid connection agreement according to § 8a EEG, in close coordination with the grid operator. Additionally, we are preparing robust economic feasibility calculations that take into account redispatch risks as well as additional revenue potentials – for example, from Control energy or energy trading – take into account. Through the coordinated and parallel implementation of PV and storage projects, we ensure that grid expansion is technically efficient and economically successful.
Conclusion: From Network Bottleneck to Flexibility Strategy
Grid overlay with PV and BESS transforms the challenges of the 2026 grid package into competitive advantages. While the redispatch reservation complicates investments, the grid connection point can be better utilized, creating:
- Shorter project durations (no network expansion)
- Higher energy yields (better annual utilization)
- Ancillary revenue through flexibility markets
- System post for grid stability
Companies that are rethinking now are strategically positioning themselves better for the energy transition.