Nord Pool’s New European BESS Revenue Index ‘Reduces Trader Bias Risk’ for Merchant Plays

Why It Matters

By offering a transparent, data‑driven benchmark, the index lowers perceived counter‑party risk, making merchant BESS projects more attractive to lenders and accelerating financing for storage assets across Europe.

Key Takeaways

• Clean Horizon's index simulates an average trader’s revenue for BESS projects
• Index provides a transparent benchmark to reduce trader bias risk for owners
• Can be embedded in merchant offtake contracts, improving bankability for lenders
• Model assumes 85% round‑trip efficiency and 1.5 cycles per day
• Battery duration (1‑4 h) affects revenue based on energy vs ancillary markets

Pulse Analysis

The rapid expansion of battery energy storage systems (BESS) across Europe has outpaced the development of standardized performance metrics. Lenders and investors often struggle to assess the commercial viability of merchant‑only projects, where revenue depends entirely on market participation. Nord Pool’s new Clean Horizon Storage Index fills that gap by providing a transparent, model‑based benchmark that reflects what an average, unbiased trader could earn under prevailing price and weather conditions. By anchoring revenue expectations to a consistent reference point, the index helps de‑risk financing and aligns stakeholder expectations.

At the core of the index is the COSMOS simulation engine, which processes historical price data from day‑ahead, intraday, aFRR and mFRR markets while applying uniform technical assumptions—85% round‑trip efficiency, 100% availability and 1.5 cycles per day. The tool generates a virtual trader profile for each battery duration (1‑, 2‑, and 4‑hour) and calculates the revenue that such a trader would have captured each month since 2023. This approach isolates performance from individual optimiser strategies, allowing asset owners to compare actual results against a market‑wide average rather than a single counterpart’s track record.

The practical impact is immediate. Asset owners can now embed the index in merchant offtake contracts, guaranteeing a floor tied to the index while still exposing both parties to upside potential. Traders benefit by showcasing performance that meets or exceeds the benchmark, building credibility with clients. For banks and private‑equity sponsors, the index reduces the “trader bias” component of credit risk, making BESS projects marginally more bankable. As the European storage market matures, such standardized benchmarks are likely to become a prerequisite for large‑scale financing, driving broader adoption of longer‑duration batteries in markets where energy revenues dominate and encouraging shorter‑duration assets where ancillary services are more lucrative.