Paid on contract, or squeezed on spread: Europe battery market is on split

The week of 30 September to 7 October 2026 made one thing plain: how a battery locks in revenue now decides whether it gets built. Poland saw the largest battery tolling deal yet signed in the EU plus a fresh financing close, both resting on long-dated contracts, while Bulgaria became the live test of what happens when a fleet grows on merchant spreads alone. Spain showed a third path through co-located hybrid contracts, and every figure below links to its source.

1. Poland is paying its batteries up front, on contract

Statkraft and Greenvolt signed a 10-year tolling agreement covering 400MW of battery storage across two operating Polish projects, the Elłk and Turośń Kościelna systems (each 200MW/800MWh). Greenvolt called it the largest publicly communicated BESS tolling deal in the EU to date. Under it, Statkraft decides when the batteries charge and discharge across energy and flexibility markets in return for a fixed payment, adding a second layer of contracted revenue on top of the capacity market contracts both projects already hold.

The structure is becoming the norm rather than the exception. Jakub Kupcu of investor Claritas Investments notes that Polish storage has secured more than 11GW of capacity market contracts, yet returns on newly built CM-contracted assets have compressed by roughly a third in recent years, and layering a toll or floor on top of a bare CM contract can lift the share of project cost covered by debt from about a third to nearly two-thirds, while extending loan tenors from under a decade to well beyond ten years. Days earlier, Canada's Northland Power closed roughly PLN500 million of debt, alongside about PLN280 million of grants, for its 300MW/1.2GWh Mieczysławów and Kamionka projects, which carry 17-year capacity market contracts and are due online in 2028. Northland expects the pair to contribute around CA$40 million to CA$50 million of combined annual adjusted EBITDA, and its advisers framed the close as a sign of lenders' growing appetite for the Polish market.

What this means if you own or develop BESS. First, line up a route to market, a toll, a floor or an offtake, before commercial operation rather than after, because contracted revenue is what moves lenders now. Second, stack it: a capacity payment on its own is a thinner base than it used to be, so a toll or floor on top is what pushes debt up and tenors out. Third, keep the upside, because the point of a modern toll or floor is to secure the core economics while still capturing value across day-ahead, intraday, balancing and ancillary markets through active dispatch.

That last part is our day job. Fusebox integrates and dispatches BESS, PV, EV chargers, HVAC systems and C&I industrial loads on a single platform, and we operate across 15 European markets and 9 TSOs.

Talk to Fusebox about routing a new battery to market →

2. Bulgaria shows what merchant-only revenue does at scale

Renalfa IPP and Eurowind inaugurated the Tenevo complex in southeastern Bulgaria, pairing 242MWp of solar with 311MW/772.5MWh of co-located battery storage, with 250MW of wind planned later. It was financed with €50 million from the EBRD and €53 million from Raiffeisen Bank International, the first project to carry an InvestEU guarantee, and the EBRD described it as a sizeable merchant project. Renalfa's Ivo Prokopiev called it the first showcase in Europe of a dispatchable renewable asset of that scale.

The backdrop is unusual. Bulgaria now runs around 5.4GW of operating batteries, equal to 22.8% of its installed power capacity, which makes it the most battery-intensive power system in the world (California sits at 14.9%). With roughly another gigawatt due in the coming months, those batteries are starting to reduce the very price spreads and balancing revenues that drew the first investors, and the economics of the next projects look harder. The flexibility has earned its keep: in July and August the country ran net exports of around 830GWh a month, more than twice its spring average, as drought cut regional hydro and nuclear output. The read-across for owners everywhere is that holding a battery is no longer the hard part. Results now depend on dispatch strategy and access to more than one market.

For asset owners in fast-filling merchant markets, the move is to stop underwriting today's spread. Co-locate where you can, lengthen duration, and spread revenue across arbitrage, balancing, ancillary and, where available, contracted layers. If you just want to pressure-test how saturated your market's spreads really are, our knowledge bot can walk you through the basics, but the real value is in the dispatch.

Talk to Fusebox about dispatching across every market, not just one →

3. Spain is making co-located hybrids bankable

Zelestra and EDP added two more hybrid power purchase agreements in Spain, bolting 462MWh of batteries and 181MWdc of solar onto existing plants at Pedroso (Seville) and Valkyria (Castilla-La Mancha). That takes the storage under their Spanish hybrid PPAs to 1,022MWh. The structure, which Zelestra has described as "PPA 2.0", uses the battery to flatten an otherwise solar-shaped output curve so the offtaker can contract a steadier profile. Spain chief Jaime Burguete said the deals show energy storage is bankable in Spain and expects co-located storage to be the market's main growth area in the coming years. The same company recently signed a comparable solar-plus-storage PPA with steelmaker Salzgitter Flachstahl in Germany (147MW of solar, 273MWh of batteries), so the model is travelling.

For PV owners and portfolio managers watching capture prices fall, co-location is the hedge hiding in plain sight. A battery on an existing grid connection protects the value of midday generation and opens a contracted, flat-curve offtake that a bare solar plant cannot offer. If you are weighing whether to add storage to a PV site, bring us the connection and the generation profile and we will model the stack.

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Regulatory and market watch

• The Energy Storage Summit Central and Eastern Europe runs in Warsaw on 6-7 October, the clearest read this week on where CEE and Baltic capital and policy are heading.
• Wärtsilä closed its Valo storage joint venture with RCT Solutions on 1 October (more than 20GWh across 130-plus projects), expecting an operating loss in 2026 and a return to the black toward the end of 2027, a sign of consolidation among integrators.
• Germany's first StromVKG capacity market auction announces winners on 3 November; batteries are excluded from the first tranches under the 10-hour rule, with the first battery-open generation auction set for 18 May 2027.
• Spain's capacity market auctions are still to be scheduled, following the ministerial order that took effect on 17 September.
• Across the EU, national flexibility needs assessments feed into indicative member-state non-fossil flexibility targets due by January 2027.
• The Baltic TSOs (Elering, Litgrid and AST) are due to report their Q3 2026 balancing review and the phase-out of demand-reduction reserves, which will reshape where Baltic batteries earn.