Germany nearly doubled the volume of curtailed solar photovoltaic (PV) electricity in 2024, highlighting the persistent structural pressure on the national grid. According to data published by the Bundesnetzagentur (Federal Network Agency), 1,389 GWh of solar generation was curtailed, representing a 97% increase compared to 2023. This occurred despite a 17% drop in total grid congestion management costs, which fell to 2.776 billion euros for the year.

The surge in PV curtailment is driven by two overlapping dynamics: Germany’s aggressive renewable expansion and favorable weather conditions.

During the summer of 2024, the country recorded exceptionally high solar irradiation, coinciding with continued growth in PV deployment. February alone saw the installation of over 1.5 GW in new renewable capacity — including 1,020 MW in solar PV, as reported by Strategic Energy.

The southern federal state of Bavaria bore the brunt of the curtailment, with 986 GWh of solar generation cut from the system. This aligns with the state’s dominant share of distributed PV and reflects the limits of current grid flexibility in absorbing midday peaks.

Despite this setback, the overall performance of the renewable sector remained strong. Curtailment across all renewables accounted for just 3.5% of total generation, implying that 96.5% of clean electricity reached end consumers — a figure the agency considers a milestone, given the pace of deployment.

Re-dispatch intensifies in Q4 amid wind surge

The fourth quarter of 2024 presented significant operational challenges. Re-dispatch volumes rose by 19% year-on-year, reaching 10,424 GWh, a clear spike compared to Q4 2023. The rise was largely attributed to a prolonged high-wind event in December, which led to excessive offshore wind generation, surpassing the capacity of the existing transmission infrastructure.

In response, re-dispatch measures involving offshore wind increased from 1,504 GWh to 1,812 GWh, while the use of network reserve power plants surged from 291 GWh to 797 GWh. This marked shift came as Germany’s Power Plant Availability Act expired, reinstating numerous thermal assets into reserve status.

As a result, natural gas and hard coal plants played a greater role in system balancing, contributing 4,151 GWh and 3,792 GWh, respectively. Regional data show North Rhine-Westphalia and Baden-Württemberg as focal points of these re-dispatch operations due to their proximity to demand centers and existing thermal infrastructure.

Source: Bundesnetzagentur

Transmission vs distribution: shifting grid stress

Although the majority of bottlenecks remained within the transmission network (74%), 2024 saw a noticeable shift towards distribution networks, which now account for 26% of congestion in renewables, up from 20% in 2023.

This trend underscores the impact of distributed solar installations on local grid resilience. As prosumers and small-scale installations grow, local lines become increasingly saturated, particularly during high-production hours.

Curtailment also affected wind generation, although less severely than solar. Offshore and onshore wind plants were curtailed by 4,562 GWh and 3,384 GWh, respectively — decreases of 20% and 15%. The largest reductions occurred in Lower Saxony and Schleswig-Holstein, traditional wind hubs with limited export routes.

Cost dynamics: diverging impacts by technology

While overall congestion management costs dropped, the cost differential between technologies remains significant:

• Renewable re-dispatch averaged €200/MWh, down from €216 in 2023.

• Conventional plant re-dispatch averaged €142/MWh, up from €129.

These figures include financial compensation to plant operators, market balancing costs, and activation of reserve assets. Renewable curtailment cost 554 million euros, just 4% less than the previous year, despite a 10% decline in curtailed volume due to lower wholesale electricity prices reducing the market premium paid to affected operators.

Germany’s grid reserve will also become more expensive in 2024. Fixed and activation costs rose to 1.028 billion euros, nearly doubling from 2023. This is largely attributable to the increased number of units reinstated into reserve status after legal changes.

Strategic outlook: progress with caveats

Germany continues to make strides in renewable integration, but 2024 illustrates that infrastructure remains a bottleneck. The significant rise in PV curtailment, alongside late-year re-dispatch spikes, reveals the fragility of the current grid architecture under weather-induced generation surges.

“Renewable integration is progressing, but the system still relies on costly temporary measures to avoid overloads,” the Bundesnetzagentur notes.

Looking forward, Germany will need to accelerate investment not only in transmission expansion but also in storage, flexible demand, and digital grid controls to prevent curtailment from undermining energy transition goals. Without these complementary assets, even record deployment levels risk producing diminishing returns for both operators and the climate.