GIE AGSI+, the Gas Infrastructure Europe platform that publishes daily European storage submissions, recorded German net injection of 246.5 GWh on Wednesday 22 July, one gas day after the 0.8 GWh reading of Tuesday 21 July1. Injection then climbed to a window peak of 540.9 GWh on Sunday 26 July and stood at 373.2 GWh on Wednesday 29 July. National fill moved up from 45.53% across those nine days.
German caverns hold the largest working gas volume in the European Union, and the rate at which they take gas in over summer is the single clearest read on how the bloc enters winter. That is why a one-day stall drew attention. This desk led update #29 with Germany's caverns stopping their bid for prompt gas and tied it to the clean spark spread turning negative on 20 July. The stall lasted one gas day. We hedged it at the time as too short to call a structural halt, and the hedge resolved against us.
The reason the two things were never joined is that cavern economics and turbine economics run on separate clocks. A negative spark spread takes a CCGT (combined-cycle gas turbine) off-merit today, because the plant cannot cover fuel and carbon out of the day-ahead power price. A storage operator sells nothing into the day-ahead market and never sees that signal. The operator buys at the prompt and sells against the winter strip, and through that week German gas-fired output kept falling on cheaper fuel while the operators below ground carried on buying at TTF (Title Transfer Facility) near €58 to €602.
The 22 July restart therefore resumed a purchase programme that a single missing day in the AGSI+ series had made look like a decision.
