Wind Hybridisation Model — Evaluate Co-located BESS on an Existing Onshore Wind Farm Across 8 Markets

Description
If you develop, advise on or finance battery co-location on existing onshore wind farms, you know the problem: wind hybridisation has a financial logic that is categorically different from solar hybridisation, and different again from a standalone BESS. The BESS charges from a generation source that produces energy at night, during storms, in winter — precisely the hours when solar cannot charge it. The connection constraint is less severe than in solar because the wind farm does not monopolise the grid connection during peak hours. And there is a fourth revenue stream that does not exist in any other BESS context: curtailment recovery, where the battery absorbs energy that the wind farm would otherwise be forced to waste by grid operator instruction and re-injects it during peak demand.
This model handles all three of these specificities correctly, in one place, across 8 markets.

Open it, enter the existing wind farm data — capacity, production, curtailment rate, connection capacity and incentive regime — then size your BESS and allocate revenue streams. The model runs the wind as-is baseline and the Wind+BESS hybrid in parallel, shows the incremental NPV the BESS adds, and calculates the BESS incremental IRR against the wind baseline. All from a single control panel.


What makes it different from the PV Hybridisation Model
The curtailment recovery stream is the key differentiator that makes this a wind-specific model rather than a reskinned solar tool. Wind curtailment — grid operators instructing the farm to reduce output during low-demand periods, congestion or negative prices — runs at 3-5% of annual production in Italy and Spain and 5-8% in the UK and Nordic markets. The BESS absorbs curtailed energy and re-injects it during peak demand, recovering value at the merchant price. The curtailment recovery revenue is calculated as curtailed MWh multiplied by the curtailment value per MWh — a country-specific parameter calibrated separately from the arbitrage spread — and the BESS curtailment capture rate is separately configurable to reflect the BESS capacity constraint relative to the curtailment volume.

The usable capacity factor for the BESS defaults to 75% in wind co-location versus 80% in solar, reflecting the different dispatch profile: wind produces at night and in winter, which means the connection is available to the BESS during more hours, but the dispatch timing is less predictable than in solar, reducing the effective capture rate relative to rated capacity. This distinction is not cosmetic — it materially affects the BESS incremental IRR calculation.

The wind baseline engine models gross production, applies the annual curtailment loss to calculate net exported production, then applies degradation at 0.60%/year and OPEX escalation at 2.5%/year across 20 years. Incentive revenue is correctly projected until the contract expiry date and then switches to market revenue, capturing the incentive cliff that is the primary driver of the hybridisation decision in Germany, Italy and the UK. The incremental BESS IRR is calculated against this wind as-is baseline — not against zero — which is the only economically correct framing of the investment decision.

The incentive interaction module reflects the specific regulatory position of BESS co-location in each market. In Italy under D.L. 21/2026, all five CE options remain available — in Mode 3, repowering with Quota A/B split increases the wind capacity and therefore the curtailment volume, making the BESS curtailment recovery stream proportionally more valuable. In Mode 5, the exit indemnity can partially fund the BESS CAPEX. In Germany, the BESS earns fully separate market revenues without affecting the EEG contract. In the USA, the ITC 30% applies to the BESS CAPEX under the IRA as a standalone qualifying investment, and the wind PTC is unaffected.


Who this is for
Developers and asset managers evaluating BESS co-location on existing onshore wind farms where curtailment is a significant and growing source of value loss, particularly in congested grid areas in the UK, Germany and Nordic markets. Financial advisors preparing business cases for wind hybridisation investment where the incremental BESS IRR and standalone BESS DSCR need to be demonstrated to lenders separately from the wind plant metrics. Infrastructure investors reviewing wind portfolio assets for hybridisation upside, particularly where incentive expiry is approaching and the BESS provides a revenue diversification rationale alongside the curtailment recovery case.


Workbook: Cover · CONTROL_PANEL · WIND_INPUTS · BESS_INPUTS · INCENTIVE_CONFIG · BASELINE_ENGINE · HYBRID_ENGINE · COMPARISON_ENGINE · FINANCIAL_MODEL · DASHBOARD.


For custom versions, country extensions or specific requests, contact us at [email protected]