4.1 BESS on the rise: A tale of two market types Broadly, two distinct BEsS market archetypes have emerged across Europe. The first comprises more mature markets, where the business case is largely driven by merchant participation in different markets, allowing assets to stack revenues from multiple streams. Great Britain serves as the role model, followed by Germany, the Netherlands, Belgium, and the Nordics. The second group consists of emerging BEsS markets, where public support mechanisms play a central has also underpinned the first wave of BEsS deployments in Southeastern Europe. In more advanced markets lacking CAPEX subsidy schemes, BESS projects rely on a diversified revenue stack - that is, the ability to capture value across multiple markets, including short-term wholesale the complexity inherent in multi-market optimization strategies led to a boom in fixed-revenue FPAs. But it is in Germany where the merchant opportunity really shone in 2025, thanks to a volatile market environment, combined with a still limited supply of storage flexibility, and amplified spreads in the prices rising sharply mid-year and remaining the main source of merchant revenues.