How to read outage disclosures against the day-ahead gate

Each row is a unit: its name, fuel, installed capacity, the area it is published under and the publisher. Each column is a delivery hour of the zone's local day, 23, 24 or 25 of them across a clock change. A cell shows the megawatts published as unavailable in that hour and a shape that says when the hour was first disclosed. A dot means no notice covers the hour.

The megawatts come from the latest version of each message only. Within a message the largest figure among the periods touching the hour is used, and where one unit has several messages the largest of them is shown rather than their sum, because two messages for one unit usually restate or extend one outage. That understates the rare day on which a unit has two genuinely separate partial outages. A message whose newest returned version is marked outdated is left out, because the version that replaced it was not returned and what it says is not known to hold; the console page says how many were set aside.

German units are published under the grid operators' control areas rather than under the bidding zone itself, so for Germany-Luxembourg the view reads the zone and its control areas together. Consumption units are included alongside production and generation units. Great Britain is not served here, nor is Switzerland, which is not in the pan-European day-ahead auction, so the gate this view measures against is not its gate. Transmission notices are not read.

The day-ahead gate is the instant the auction closed to bids, noon Central European time on the day before delivery. The pan-European auction delivers on the Central European day, so for a zone on another clock (Finland, the Baltics, Romania, Bulgaria, Portugal) the first or last hour of its local day belongs to a neighbouring auction day with a different gate. The columns stay on the zone's own clock and each hour is measured against the gate of the auction day it falls in. First disclosure is judged on what was in force at each moment. At any moment a message counts at the megawatts of its latest version published by then, if that version is active; a cancelled message, a message moved off the hour and a message not yet published count for nothing. The unit counts at the largest of its messages. The first disclosure of the megawatts now shown is the earliest moment from which the unit was in force at no less than that, and stayed so at every later publication. A notice later raised is first disclosed at the raise and not at the smaller original; an end-time extension keeps the original date; a notice cancelled and reissued under a new identifier with no gap keeps the date of the original. A gap with nothing in force starts the count again, so an outage cancelled weeks ago does not make a fresh one disclosed after the gate look early, and a small outage disclosed weeks ago never makes a large one disclosed later look early. Whether a cell is before the gate is read from the moment just before the gate: if the unit was in force at the megawatts shown then, the cell is before the gate, even if the notice was cancelled and reissued a minute after it; the first-disclosure time shown is still the start of the last unbroken stretch, which in that case is the reissue. A notice whose newest version the feed marks as moved off the day, with the time of that move unknown, counts as not in force, so the page errs toward reading a disclosure as later and never earlier.

• Before the day-ahead auction gate (filled circle): first disclosed before the SDAC day-ahead auction closed (12:00 central European time the day before delivery). The page header prints the gate time.
• After the day-ahead gate (triangle): first disclosed at or after the day-ahead gate but before the hour began. The small number beside the triangle is the next intraday auction the disclosure was still in time for: 1 for IDA1 (gate 15:00 the day before), 2 for IDA2 (22:00 the day before), 3 for IDA3 (10:00 on the delivery day). IDA3 clears only the hours from 12:00 to midnight, so a morning hour disclosed after 22:00 the day before, or an afternoon hour disclosed after 10:00, has no auction left and no number: only continuous trading could still react to it. The cell's tooltip names the auction and its gate in full. The test at each intraday gate is the one used at the day-ahead gate: whether the unit was already in force at the megawatts shown just before it. Every zone this page covers clears all of these auctions; in Italy they are called MI-A1 to MI-A3.
• After the hour began (diamond): first disclosed once the hour was already under way.

A cross marks an hour whose covering message was cancelled by its latest version: it contributes no megawatts, and is shown so that an outage that was published and then withdrawn is not mistaken for one that never existed. A down arrow marks an hour that an earlier version covered and the latest version no longer does, including a message whose newer version was not returned: the cell shows when the last covering version was published, against that hour's gate, and is never drawn as an hour with no notice. The summary line counts the hours in which at least one cell falls in the second or third class.

The second section reads the regulatory transparency platform's unavailability documents. That platform returns only the latest revision of each outage, so the time its single revision was published is not the time the outage first became public. This view shows it as the latest revision's publication time, marks every cell with a tilde, and never assigns a timing class to it.

The two sections are not matched against each other. The same outage can appear in both, and reading them side by side is the way to see a revision that the second feed has already overwritten. The reader of the second feed was written to the documented schema and had not been checked against a live response when this view shipped; the sources panel on the console page says whether that is still so.

• A planned outage disclosed weeks ahead shows as before the gate for every hour it covers, which says nothing about a different outage on the same unit.
• A revision that only extends the end time keeps the original disclosure time for the hours it already covered, and gives the new hours the revision's own time. A day at the edge of a long outage can therefore read as late for reasons of bookkeeping.
• A forced outage that begins after the gate cannot have been disclosed before it. Late is the expected reading for an unplanned failure.
• A plant reported both as a production unit and as its generating units can appear in more than one row, and the peak figure sums across rows, so it can count that plant twice.
• Where the publisher merged several units into one message, the grid attributes the message to each unit it names.

Nothing here establishes that information was withheld, known earlier elsewhere or material to the auction. It points at hours worth reading alongside the incumbent platform's alert.

The main German transparency platform is not read, because its interface is licensed, so an empty or thin German grid is not evidence that nothing was disclosed. Great Britain's disclosures are published by its own operator and are out of scope. Transmission and other market information notices are excluded. Nothing is stored: the view is read live and cached for a few minutes, so a notice published since may not appear until the cache turns over.