Europe's Intraday Power Market Runs Into Grid Physics, Montel EnAppSys Analyst Warns
Vincent Thevenin of Montel EnAppSys argues transmission grid capacity now constrains Europe's intraday electricity market more than market design, as German price extremes multiply.
German power closed at €134.87/MWh on Saturday (2026-08-15), within a market whose intraday architecture has grown steadily more sophisticated over the past decade but which, a Montel EnAppSys analysis published Wednesday (2026-08-12) argues, is now being outpaced by the physical grid that underpins it.5
Vincent Thevenin, Montel EnAppSys's German short-term markets expert, argues that Europe's intraday electricity market's future development will be shaped more by transmission capacity than by any further refinement of market economics. The grid has become the harder limit.5
The price data from recent months reflects the stress on both ends of the curve. Germany's 15-minute spot power price surpassed EUR 500/MWh on 2026-06-29, Montel reported. Negative prices tell a different story: Germany recorded them 5% of the time in 2024, up from 3% in 2023, according to The Economist, and in the first eight months of the measured period that share had risen to 10%.3,2
Scarcity spikes and oversupply crashes may look like market signals doing their job. They also expose a grid that cannot always move power to where it is needed, or absorb surplus generation when output floods the system and demand has nowhere to go. Prices go negative. A cold spell cuts wind output and demand climbs, and the spot market swings violently in the opposite direction. Thevenin's reading is that refining intraday market rules, without expanding the wires connecting generation to demand, cannot solve this.5,2
"The market is screaming for capacity," Michael Waldner, CEO of Pexapark, a Zurich-based renewable energy consultancy, told The Economist.2
Battery storage has emerged as a partial response. European grids added a record 8.8 GWh of storage capacity in 2024, ten times the volume added in 2020, according to The Economist. The arbitrage logic is clear: charge when prices go negative, discharge when they spike. But 8.8 GWh is a modest buffer for a continental grid that can swing from surplus to scarcity within a single trading session.2
Grid investment has lagged for years. The European Union's next seven-year budget proposes spending over €30bn on transmission grids, compared with €5.8bn in the previous seven-year period, a shift that reflects the accumulated shortfall. The Economist also reported a parallel problem on the connection side: entrepreneurs filing speculative grid hookup applications and holding them, blocking queue slots without committed capital.2
During winter 2025-26, Germany illustrated what happens when margin erodes. Available power capacity fell to its lowest of the season during the week of 2026-05-18, Bloomberg models showed, as wind speeds dropped and demand climbed, according to OilPrice.com. Wind generation in October and November 2025 ran 25% below the same two months in 2024.1
Nord Pool offered a market-side response in July (2026-07-06), telling Montel it plans to expand financial power futures to continental European countries in 2027. Deeper hedging markets reduce basis risk for generators and retailers. They do not move electrons across a congested corridor.4
Thevenin's argument is that the intraday market has reached a point where price signals cannot substitute for infrastructure. The €134.87/MWh close as of Saturday (2026-08-15) sits within a volatility structure that oscillates between negative prints and triple-digit spikes, a pattern driven as much by grid bottlenecks as by supply-demand balance. The redispatch costs that transmission operators pay to reroute generation around physical congestion will be the clearest measure of whether Europe's grid expansion is keeping pace with its renewable buildout.5,2