BONN (dpa-AFX) - Grid congestion once again led to the temporary shutdown of wind and solar power plants last year. "In total, curtailments of renewable energy accounted for 3.5 percent of total renewable electricity generation," reported the Federal Network Agency (Bundesnetzagentur) in Bonn. "This means that more than 96 percent of renewable energy could be fed into the grid and used by end consumers," the authority emphasized. In 2024, 3.5 percent of renewable electricity generation had already required curtailment.
The underlying issue is that while numerous wind turbines and solar parks have been connected to the grid in recent years, grid expansion has failed to keep pace. To prevent overloading existing lines, grid operators employ what is known as grid congestion management. The primary measure is a short-term adjustment of power plant dispatch, referred to as redispatch.
Electricity Consumers Bear the Costs of Congestion Management
When a line bottleneck is imminent, power producers on one side of the bottleneck are instructed to throttle their feed-in. These are, for example, wind turbines in Northern Germany that are curtailed. Simultaneously, plants on the other side of the bottleneck must increase their feed-in. These are typically coal-fired or gas-fired power plants in Southern Germany.
Plant operators on both sides receive compensation for such measures: operators of conventional power plants for additional output on one side of the bottleneck, and renewable energy operators as compensation for curtailed electricity on the other. These costs are passed on to all electricity consumers via grid fees.
Congestion Management Costs Reach 3.1 Billion Euros
According to the Federal Network Agency, the costs for total grid congestion management rose by four percent in 2025 to nearly 3.1 billion euros. The volume of measures remained stable. In 2023, costs stood at approximately 3.4 billion euros.
When feed-in from generation plants was reduced in 2025, 60 percent of the affected electricity volume originated from renewable sources. However, conventional power plants were also impacted by such measures. The energy sources most affected were lignite, natural gas, and hard coal. Grid operators also handle a portion of redispatch measures via the power exchange, where a precise allocation to specific plants is not possible.
The Federal Ministry for Economic Affairs intends to better coordinate the expansion of power grids and renewable energies in the future to reduce overall costs. According to a ministerial draft, new wind or solar parks in heavily congested grid areas will no longer receive compensation if the plants must be curtailed. Environmental associations, the Green Party, and the renewable energy industry have criticized these plans./tob/DP/zb
