The "Final Boss" of the Energy Transition: Decoding Germany’s Path Through the Dunkelflaute

BERLIN – As Germany navigates the most ambitious industrial restructuring in its modern history, a singular term has come to dominate the political and economic discourse: Dunkelflaute. Translated as the "dark doldrums," it refers to those winter periods when the sun does not shine and the wind does not blow, leaving the nation’s burgeoning renewable infrastructure momentarily dormant.

To some, the Dunkelflaute is an insurmountable barrier to a carbon-neutral future; to others, it is a technical hurdle already in the process of being cleared. According to energy expert Tim Meyer, author of the influential book Strom (Power), the challenge is significant but far from invincible. In a recent comprehensive analysis, Meyer dissects the conflicting figures regarding Germany’s "guaranteed capacity" and argues that the solution lies not in a massive return to fossil fuels, but in a sophisticated, decentralized mix of flexible assets.

Main Facts: The Numbers Behind the Power Gap

The debate over Germany’s energy security is currently defined by three distinct figures: 11 gigawatts (GW), 22 GW, and 35 GW. While these numbers are often used interchangeably in political shouting matches, they represent very different scenarios for the year 2035.

• 11 Gigawatts: This is the immediate target currently being tendered by the German federal government under the Power Supply Security and Capacity Act (Stromversorgungssicherheits- und Kapazitätengesetz or StromVKG). It represents the "safety net" the state is willing to subsidize to ensure the lights stay on during the initial phase of the coal phase-out.
• 22.4 Gigawatts: This is the figure calculated by the Federal Network Agency (Bundesnetzagentur) as the required additional steerable capacity by 2035, assuming the expansion of renewables and flexible demand proceeds according to plan.
• 35.5 Gigawatts: This represents the "worst-case" requirement if the energy transition stalls—specifically, if wind and solar expansion lags or if the rollout of smart meters and flexible consumer response (demand-side management) fails to materialize.

Tim Meyer points out that critics often weaponize the highest figure (35 GW) to argue for the construction of up to 70 new gas-fired power plants. However, Meyer’s analysis suggests that by 2035, Germany will actually require less steerable power plant capacity than it possesses today, provided the system is managed with modern flexibility.

Chronology: From Coal Dependency to Flexible Reliability

The evolution of Germany’s power grid follows a strict timeline dictated by climate targets and the physical decommissioning of aging infrastructure.

2024–2026: The Transition Phase

As of late 2026, Germany’s fleet of steerable power plants stands at approximately 65 GW, comprised of 35 GW of gas-fired plants and roughly 30 GW of combined hard coal and lignite (brown coal). Despite fears of shortages, data from energy-charts.de reveals that even in peak periods, the entire gas fleet is rarely utilized simultaneously. In 2025, for instance, the maximum simultaneous output from gas plants peaked at 24 GW.

2031–2032: The Subsidy Kick-off

Under the StromVKG passed in July 2026, operators of new plants will begin receiving "readiness premiums" starting in 2031. These payments, guaranteed for 15 years, are designed to ensure that capacity exists even if it is rarely called upon. By 2032, the government plans to transition to a full "capacity market," where storage providers and flexible industrial consumers can compete alongside traditional power plants to provide grid stability.

2035: The Coal Exit

By 2035, the landscape changes fundamentally. As coal plants go offline—driven by both policy and the increasing unprofitability of carbon emissions—the "gap" is filled by a mix of new gas plants (designed to eventually run on hydrogen) and decentralized flexibility. Total steerable capacity is projected to drop to 57 GW, which Meyer argues is sufficient because the grid will be bolstered by significantly higher levels of storage and international interconnectivity.

2045: The Net-Zero Goal

By 2045, the system must be entirely climate-neutral. Estimates for required steerable capacity range from 70 to 100 GW. However, Meyer notes that these high-end estimates often rely on a "baseload" mindset that may be obsolete by then.

Supporting Data: Redefining the Dunkelflaute

A central pillar of Meyer’s argument is that the traditional definition of Dunkelflaute is flawed. Usually defined as a period where wind and solar provide less than 10-20% of their installed capacity, Meyer argues this fails to account for the sheer volume of renewables being built. If you double the number of wind turbines, even a 10% output provides a massive amount of electricity.

The Storage Threshold

Meyer proposes a new, more practical definition: A Dunkelflaute begins only when pumped-storage hydro and batteries are exhausted, and a deficit still remains. It ends when these storages are recharged. By this logic, every additional hour of battery storage added to the grid pushes the start of a "true" Dunkelflaute further back.

Simulation Results

Simulations conducted by the Fraunhofer Institute for Solar Energy Systems (ISE) for the year 2045 demonstrate this shift. In a typical week, solar and wind are projected to cover 96% of demand. The remaining 4% is covered by hydrogen-ready backup plants. Crucially, the simulation shows that batteries can shave off the "peaks" of demand, meaning the backup plants can run at a steady, lower output rather than needing to match extreme volatility. This significantly reduces the total gigawatt capacity required.

The Role of Decentralized Assets

Germany currently has approximately 9,600 biogas plants. If converted to flexible operation with larger gas storage tanks, these plants act as a "green" steerable reserve. Furthermore, the emergence of "reversible" power plants—such as those developed by the Munich-based startup Reverion—allows for a system that can both generate electricity from biogas and use excess wind/solar power to create synthetic gas for storage.

Official Responses: Policy and Market Mechanisms

The German government’s approach has been met with both cautious optimism and rigorous academic critique.

Klaus Müller, President of the Federal Network Agency, has remained steadfast in his assessment that the energy supply is secure. "Power supply will remain secure in the future if additional steerable capacities are built," Müller stated during the presentation of the 2025 Monitoring Report. He emphasized that the 13 GW difference between the "target" and "stalled" scenarios is essentially the "price" Germany pays for any delays in the smart-meter rollout or renewable expansion.

The European Commission has also weighed in, approving the German subsidy schemes but noting the significant costs. Estimates suggest that between 2026 and 2045, the cost of maintaining this backup reserve will range from €15.6 billion to €35.2 billion. These costs will likely be passed on to consumers via grid fees, though Meyer argues this will be offset by the overall lower cost of renewable generation.

Economist Veronika Grimm and her team at the Technical University of Nuremberg have proposed an alternative to the government’s capacity market. They suggest an "insurance obligation" for energy suppliers. Instead of the state tendering power plants, suppliers would be legally required to prove they have secured enough capacity to cover their customers’ needs years in advance. This would allow the market to decide whether that capacity comes from a gas plant, a massive battery, or a contract with an industrial plant to reduce consumption during peaks.

Implications: The Death of the Baseload Myth

The most significant implication of Meyer’s analysis is the final dismantling of the "baseload" concept. Historically, the grid relied on coal and nuclear plants that ran 24/7 because they were difficult and expensive to turn off. In a renewable-heavy system, these plants are a liability because they cannot get out of the way when the sun is shining.

Economic Shift

The economics of the grid are shifting from "fuel costs" to "capital costs." In the past, the cost of coal or gas determined the price of power. In the future, the cost of building the wind turbine or the battery is the primary expense, while the "fuel" (wind/sun) is free. Consequently, backup plants will run so infrequently that the price of their fuel (even expensive green hydrogen) becomes secondary to the cost of simply having the plant standing ready.

The Digital Imperative

The success of this transition hinges on digitalization. As of autumn 2026, only a quarter of German households and businesses required to have a smart meter have actually received one. Without these devices, the grid cannot "talk" to heat pumps, electric vehicles, or home batteries to tell them to charge when power is cheap and discharge (or stop charging) when the grid is stressed.

Conclusion: Respect, Not Fear

The Dunkelflaute remains the "final boss" of the energy transition, but Meyer’s data suggests it is a boss that can be defeated through a combination of diverse technologies rather than a single "silver bullet" like massive gas plant construction.

"We have more than enough potential for guaranteed capacity to supply ourselves even in the worst-case scenario," Meyer concludes. The challenge is not a lack of technology or energy, but the speed of implementation. By focusing on decentralized flexibility, international cooperation, and a digitalized grid, Germany can move past the fear of the "dark doldrums" and into a period of stable, carbon-neutral reliability. The Dunkelflaute, it seems, requires respect and meticulous planning—but no longer justifies a state of national anxiety.