Data Quality: Where Grid Series Read Zero or Go Missing, 18 September 2026

• Data as of 18 September 2026: 50 ENTSO-E bidding zones and 14 EIA regions were checked.
• 31 of 50 ENTSO-E zones and 3 of 14 EIA regions have at least one listed issue.
• 30 generation sources read exactly zero or are missing for 14 or more days up to the end of their series.
• Demand is missing or zero for 14 or more days in a row in 3 listed runs, and was published as zero on single days in 1 listed zones.
• Generation is below 60 percent of demand in the hour of the latest mix in 9 listed zones; 8 listed zones have a capacity gap and 2 have stopped updating.
• Every figure on the site is shown as the platform published it; nothing is filled in or corrected.

Grid operators and transparency platforms publish what their members report. Reports can be late, incomplete, or a plain zero where a reading is missing. We show each figure as published and add a dated note on the zone page where a series looks wrong, rather than guess at the true value. A zero is therefore not proof that a plant stopped, and a gap is not proof that it was idle.

• Source reads zero. A generation source whose daily total was above zero earlier in the series and has read exactly zero, or nothing, for at least 14 days up to the end of the series. We cannot tell from the data whether the source stopped generating or stopped reporting.
• Demand missing. 14 or more days in a row with no demand total, or a total of zero.
• Zero demand days. Days on which the platform published a demand total of zero. A real grid does not use no electricity, so the site treats these as missing reports and leaves them out of charts, rankings and averages.
• Generation coverage low. In the hour of a zone's latest generation mix, the sources reported add up to less than 60% of demand, so the generation report looks incomplete.
• Capacity gap. The zone has hourly data but no installed capacity table, or the platform reported a capacity total of zero.
• Series stopped. The newest reported day is more than 14 days older than the export. The page is kept as a historical record.

Only ENTSO-E bidding zones and EIA regions are checked here. Ember statistics for countries are annual and monthly totals and are not part of this register. See the methodology for how each layer is built.