When is continued operation more economic than repowering?

When running costs (OPEX, insurance, repairs) stay clearly below the achievable electricity price, the turbine is still running reliably from a technical standpoint, a lifetime-extension assessment confirms the residual structural stability, and no repowering permitting window is open for the site. In low-wind years with high market prices, post-EEG operation can carry the business case economically for several years.

When is repowering the better choice?

When the new turbine raises the yield by a factor of 2 to 3, the permitting situation is stable, the investment achieves an IRR in the high single-digit percent range over 20 years, and the lease environment allows a repowering step. With a 1:1 repowering at an established site, the acceptance hurdles are also lower.

Guide · Decision logic

When does continued operation make more sense than repowering?

In short: If the turbine is still running cleanly from a technical standpoint, OPEX stays well below the market price and no repowering permitting window is open, continued operation is often the right bridge. But as soon as a repowering project with a clearly higher yield and stable permitting becomes feasible, the answer is usually repowering — the site then delivers a multiple of the output.

The five decision levers

Lever	argues for continued operation	argues for repowering
OPEX vs. electricity price	OPEX clearly below electricity price	OPEX approaching the electricity price
Technical condition	low wear, manufacturer support available	frequent failures, spare parts scarce
Residual structural stability (lifetime extension)	assessment confirms continued operation	assessment reveals risks
Permitting window	no repowering possible (setback, protected area)	site is suitable, authority signals go-ahead
Lease/acceptance	short-term stable relationships	willingness for higher lease + long-term contracts

The Repowering IRR calculator provides a quantitative classification — it shows from which electricity price and which turbine class the project tips over.

The math for continued operation (post-EEG)

Without EEG (Erneuerbare-Energien-Gesetz / Renewable Energy Sources Act) remuneration, the turbine carries itself as long as:

(market price − direct-marketing cost) > (OPEX + insurance + bond reserve)

With every annual replacement of the generator or gearbox, OPEX rises. Post-EEG OPEX is typically in the range of 30 to 40 EUR per MWh, with a tendency to increase as the turbine ages. If the market price (e.g. secured via a PPA) lies clearly above that, continued operation makes sense.

The math for repowering

A modern turbine generates, at the same site, typically 2 to 3 times the output of the old turbine. The investment (on the order of 1.0–1.5 million EUR per MW) must, out of the revenues, deliver an adequate return over 20 years — banks usually expect a DSCR ≥ 1.2 and IRR targets in the high single-digit range (see Wind farm financing).

Hybrid in practice: the turbine is often kept in operation for 3–5 years while the repowering procedure runs. This keeps the site generating revenue, and the repowering start coincides with the end of the old turbine's economic reach.

Frequently asked questions

How long does the lifetime-extension assessment run?

It extends the type-certificate duration by, as a rule, a further 5 to 10 years, provided the residual structural stability is demonstrated. After that, it can be reassessed.

What happens to the old lease agreement?

With repowering it is usually redrafted or extended — see the guide Lease agreement in repowering.

Can I plan both in parallel?

Yes. As long as the repowering procedure is running, the old turbine can legally keep operating — up until the new turbine is commissioned. A clearly planned transition avoids revenue-free phases.

Continued operation or repowering decision logic: five levers determine the choice. OPEX vs. electricity price, technical condition, residual structural stability via lifetime-extension assessment, permitting window and lease acceptance. Continued-operation formula: market price minus direct marketing must be greater than OPEX plus insurance plus reserve, post-EEG OPEX 30-40 EUR per MWh. Repowering delivers yield times 2-3 at 1.0-1.5 million EUR per MW investment, IRR target high single-digit percent, DSCR at least 1.2. Practical hybrid: 3-5 years of continued operation while the repowering procedure runs

Continued operation or repowering – decision logic with 5 levers, formulas and a hybrid approach

Weighing continued operation against repowering for a specific site? We connect you with the right engineering firms and project developers for an assessment.

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