The energy transition in Germany is facing a paradoxical challenge: As the demand for renewable electricity increases significantly, world-class renewable locations are becoming scarce. But the solution is often not to develop new areas, but to upgrade the existing ones. Repowering is the key to unlocking the full potential of wind and solar farms. Bernd Müller, Head of Infrastructure Asset Management at Commerz Real, identifies the opportunities and challenges. 

Onshore wind: Why repowering is more than a simple device exchange

What sounds like a simple component replacement for laypersons is actually an operational masterpiece. “Onshore repowering is a highly complex task,” emphasises Bernd Müller, Head of Infrastructure Asset Management at Commerz Real. Because the new generation of systems has radically shifted the dimensions: Hub heights and rotor diameters of up to 180 metres as well as rotor blades above the 90-metre mark present completely new challenges for implementation:

• Foundations: Since the static loads of these new giants have increased significantly, a complete new construction of the foundations is inevitable
• Logistics: The sheer size of the components requires logistical precision work for transport through grown infrastructures
• Legal basis: Modern systems often require different distances and surface cuts. This means that leases and permits often have to be completely renegotiated

Despite these hurdles, 2026 marks a turning point. A decisive lever for economic efficiency is a new regulation: Since 2025, it has been legally permissible to “overbuild” grid connection capacities.  

This means that more generating power may be installed on an existing grid connection than the line can absorb in extreme cases. As wind farms rarely feed in their full power at the same time, the losses due to capped capacities are often negligible, according to Bernd Müller.  

To ensure that potential power peaks are not left unused, the focus is on integrated battery storage systems. They collect excess energy, thus stabilising the project and making the flow of electricity plannable. This technological leap is also changing the requirements for financing. New models are emerging that view infrastructure and storage technology as a unit. 

Photovoltaics: The new era of efficiency through repowering

Although solar farms are usually younger than wind turbines, the era of repowering has already begun. By using existing grid connection points, the generation capacity can be increased with significantly reduced investment costs. The technological potential at the same location is often underestimated: Through the interaction of highly efficient module generations, optimised use of space and intelligent system architectures, production can often be more than tripled.

Circular economy: Dismantling as an ecological opportunity

In addition to increasing performance, the focus is on ecological aspects. Critical voices often talk about dismantling old plants - but the facts speak for themselves: Repowering is the starting point for a functioning circular economy. With a recycling rate of around 90 percent, the majority of the components, in particular concrete and steel, can already be recycled today. ¹ For photovoltaic systems, this is even 95 percent.²

The challenge in wind turbines lies in the composite materials of the blades (glass and carbon fibres). But here too, industry and research, such as the Fraunhofer Institute, are constantly advancing solutions for high-quality recycling.³ These findings are directly incorporated into the design of the next generation of plants, which rely on “Design for Recycling”.  

From an environmental point of view, repowering offers clear benefits:  

• Surface protection: No new infrastructure development is necessary  
• Species protection: State-of-the-art bird and bat protection technologies can be integrated directly into the new wind turbines

The Federal Office for Nature Conservation (BfN) expressly supports this approach in order to make the expansion of renewables as area- and nature-friendly as possible. ⁴

Systemic synergies: Teamwork as a success factor

In addition to repowering, hybridisation is a key growth lever. Adding photovoltaics to existing wind farms (or vice versa) creates valuable synergies: In combination with battery storage systems, electricity yields are “smoothed” and the existing grid infrastructure is used ideally. However, the decisive success factor is the symbiosis of repowering, high-performance networks and storage. As power peaks at the site increase massively due to repowering, battery storage systems are the imperative consequence: They absorb energy in a grid-friendly manner, stabilise “overbuilt” connections and thus maximise the economic efficiency of the entire site.  

For klimaVest, this holistic approach means not only investing in individual plants, but also occupying the strategic hubs of the energy transition. In this way, we support the future viability of the portfolio and make an important contribution to the transformation of the European energy system.