What happens to wind turbines after 20 years?

When wind energy expanded in the early 2000s, it came with a 20-year promise: a fixed feed-in tariff under Germany's Renewable Energy Sources Act (EEG). That funding window is now closing for more and more turbines – raising a surprising question.

An invisible crisis of the energy transition

After 20 years, many wind turbines are far from worn out. Rotors turn, generators produce power. And yet thousands of fully functional turbines face dismantling. The reason is rarely wear and tear – it is economics.

Not a technical problem, but an economic one

Without the guaranteed tariff, turbines have to compete at the market price for electricity. For a single, older turbine that can quickly become tight: maintenance, insurance and administration continue while revenue fluctuates. The choice between "continued operation" and "dismantling" is therefore primarily a business decision.

Bundling instead of single-asset risk

In other asset classes the principle is well known: bundling many individual holdings smooths out the swings of any single one. Applied to continued operation, this means that when several sites are considered together, outages, maintenance peaks and yield fluctuations are spread out – the portfolio becomes more stable than any single turbine on its own.

Continued operation beats rebuilding – ecologically, too

Keeping an existing turbine running avoids the embodied energy locked into the steel, concrete and transport of a new build. As long as a turbine runs safely and efficiently, continued operation is usually the more resource-efficient option compared with dismantling and rebuilding.

So the question "What happens to wind turbines after 20 years?" has no technical answer, but an entrepreneurial one – and that is exactly where the real lever of the next phase of the energy transition lies.