Europe's 15-minute power market has raised volatility and risk, six months on
A Montel EnAppSys analysis published Wednesday identifies five structural lessons from the settlement shift, with balance responsible parties bearing the widest new exposures.
Europe's shift to 15-minute day-ahead power trading has delivered higher volatility and increased risk, Montel EnAppSys Nordic market analyst Priyanka Shinde concluded in a review published Wednesday (2026-07-15), labelling the characteristic price pattern "the sawtooth effect" and drawing five lessons from six months of the new settlement regime.4
The analysis lands mid-season. Two months into what Montel EnAppSys described as a "season of sub-zero prices," European power markets have been running through more negative price intervals than earlier outlooks indicated. Andre Bosschaart, head of analytics at Montel EnAppSys, noted the market has diverged from his earlier assessment. Negative prices that would have averaged out over a full hourly settlement window now hit individual 15-minute intervals directly — the exposure is immediate and specific in a way it was not before.2
The original case for the transition was well-founded. Finer time resolution better reflects how quickly supply and demand conditions actually change — generation trips, wind ramps, cross-border capacity shifts — and improves intraday market coupling. Analysts speaking to Montel said participants broadly still support the move six months on. The downside has just taken time to measure.1
Volatility within hourly bands is higher than under the old framework. Risk exposure for balance responsible parties has widened. These are the central findings, and they describe what Shinde's sawtooth label captures: short-duration events that resolve before the hour ends but register their peak price in individual 15-minute intervals. Hourly averaging smoothed these signals into the background; 15-minute settlement renders them explicit.1,4
The hedging gap is the structural problem that follows. Instruments built around hourly products do not translate cleanly to 15-minute settlement. Day-ahead contracts in 15-minute format exist, but bid-ask spreads remain wider in the granular products than in their hourly equivalents. Some participants are carrying 15-minute settlement exposure without an efficient hedge in place, Montel reported.1
France is drawing regulatory conclusions. The country's energy regulator CRE launched a consultation in April (2026-04-14) on whether to strengthen financial incentives for balance responsible parties ahead of a 2029 EU rule change that tightens imbalance pricing. At 15-minute resolution, the frequency of imbalance events for any given portfolio rises. CRE's early consultation suggests the regulator has concluded the 2029 reform will carry greater consequences in a 15-minute world than it would have under hourly settlement.3
Shinde's framing as a Nordic market specialist shapes where the analysis finds its most direct application: a region that trades into Continental European hub prices through cross-border auctions that now clear at 15-minute intervals, and where the settlement change arrived as part of the broader European harmonisation. The Nordic market shares the 15-minute settlement risk through the same cross-border coupling that drove the harmonisation of the trading window.4
Six months of live data have not included a European winter. Spring and summer 2026 brought surplus renewable generation and persistent negative prices — not the most demanding conditions for testing how 15-minute risk management holds under load. The winter period, with sharper demand variation across the day and higher penalties for forecast error, is what lies ahead. France's 2029 balancing reform, and how quickly liquidity in 15-minute hedging products deepens, will together determine how much the framework's cost rises when the season demands more of it.4,1,3