Cross border electricity trade generates about 32 billion euros in economic surplus each year in the European Union’s day ahead market alone, the EU energy regulator ACER said in its 2026 Monitoring Report published on November 4. Further integration across all market timeframes could deliver at least another 4 billion euros a year.
Integration is operationally deepening. Day ahead trading has largely moved to 15 minute products, introduced on October 1, 2025, which now account for almost 90 percent of electricity traded day ahead, and power purchase agreements increasingly pair renewable generation with storage. Price differences between bidding zones are widening at the same time, which raises the value of the transmission capacity that lets cheaper power reach higher priced zones.
That capacity is the shortfall. The requirement to make at least 70 percent of capacity available for cross border trading is not yet fully implemented across the EU, and markets operating closer to real time, intraday and balancing, are particularly affected by limited access. Forward market liquidity remains concentrated in a few bidding zones and falls rapidly for contracts beyond one year ahead.
The cost of the bottleneck is measurable. Managing grid congestion cost 5.4 billion euros in 2025, up from 4.3 billion euros in 2024, with a growing share linked to voltage control following the Iberian blackout. ACER said delayed integration projects alone would have delivered about 700 million euros of surplus in 2025 had they been implemented on time. The report lands the same week Eurostat showed EU industrial gas and electricity prices falling; ACER’s point is that market design, not just fuel costs, now decides how much of that relief reaches consumers.