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Method note · estimate

The midday ramp-down of dispatchable plants

What it measures

How far reactors, coal, gas and hydro plants ran below their daily peak at midday in spring, per zone and fuel, and the price in those hours.

Inputs

  • ENTSO-E actual generation per production type for each bidding zone on the canonical hourly grid, the dispatchable fuels and the wind and solar fuels, for the spring window stated on the view
  • Each zone's day-ahead price on the canonical hourly grid for the same hours
  • The pipeline's lifecycle emission factors per fuel, as on the Carbon Intensity view
  • A sourced full-cost figure per megawatt-hour for a fuel, where the pipeline's configuration holds one; the view offers no figure nobody sourced

Method and weighting

For each zone, each dispatchable fuel at or above the floor stated on the view, and each local day in the spring window, the day's highest hourly output stands in for the capacity available that day. The energy run below the peak is how far the midday hours fell short of it, summed; a ramp-down day is one whose midday low sits at least the stated share of the peak below it. Both are estimates. The midday price, the hours at or below the floor and the carbon intensity are measured from the same hours, as on the Carbon Intensity view. The fixed-cost illustration multiplies the energy run below the peak by a sourced full-cost figure and exists only where the pipeline holds one.

Window

The spring months stated on the view, in the latest year the generation record covers in full for the zone, refreshed on the 1st and 15th of each month; a zone short of complete days is reported as awaiting its source. The current window runs from to . Data last refreshed on .

Known limits

  • The day's peak stands in for available capacity, so maintenance step-downs and export limits read as a ramp-down; the figure is an upper estimate of what solar alone caused.
  • The hourly grid averages a quarter-hour market onto the hour, so a short, deep dip reads shallower than the market priced it.
  • A fuel below the floor stated on the view is left out for the zone; a day short of the minimum hours is a gap.

Used on

Sources: ENTSO-E. Each is described on the Data sources page.