Update: At around midday, National Grid ESO confirmed that it had now stood down the coal units, as it had adequate capacity for the coming evening.
National Grid ESO has called on its coal contingency units to warm, as prices surge to record highs.
In the early hours of this morning (12 December), the operator issued Balancing Mechanism Start-Up Instructions to two of Drax’s units, asking them to warm-up so that they can act as a backup during the tight margins expected this evening.
The move followed National Grid ESO issuing its fifth Demand Flexibility Service (DFS) test notification. This is set to run from 17:00-19:00 – the longest test so far – with 300MW per half an hour required – also the largest of the tests so far.
At the time of writing, the operator had secured between 149MW and 155.36MW for each of the half-hour periods.
Both the DFS and contingency coal contracts were set out in National Grid ESO’s Winter Outlook report, wherein the operator stated it was ”cautiously confident” despite the expected challenges of this winter that it could keep the lights on.
With the snow and cold weather across Britain, along with low wind generation, today marks the biggest challenge for the grid so far this season. Day Ahead prices surged to a record high of £2585.8/MWh for the evening peak as a result.
Calling on contingency coal
At the ESO’s Autumn Markets Forum in September, it set out that the contingency coal contracts will be the last ‘Enhanced Action’ – those it relies on when its everyday actions prove insufficient for balancing demand and generation – which it will call on.
Beyond these actions, which include emergency assistance from other system operators via interconnectors and the use of the DFS, the operator will have to turn to ‘Emergency Actions’ to protect the grid. This could include rolling blackouts.
It signed contracts with Drax, EDF and Uniper earlier in the year to give an additional 2.5GW of buffer capacity. The cost of these contracts set to be between £340 million and £395 million, subject to the procurement and use of the coal.
Name |
Volume |
Date |
West Burton A (EDF) |
2 x 400MW |
1 Oct 2022 – 31 Mar 2023 |
Drax |
2 x 570MW |
1 Oct 2022 – 31 Mar 2023 |
Ratcliffe (Uniper) |
1 x 480MW |
Nov 2022 – 31 Mar 2023 |
Dispatch of the assets is being managed via the BM, with a price of £0/MWh which is system flagged. Following on from the event in which the coal asset is used, the ESO will withdraw the Bid Offer Acceptance (BOA) and replace it with a price of £99,999/MWh.
Today’s call on T_DRAXX-5 and T_DRAXX-6 is the first time National Grid ESO has had to use these contracts this winter, with the warning made through SONAR as expected.
It takes between 12 and 48 hours to warm a coal unit, and Drax 5 is set to synchronise at 11:15, and Drax 6 at 12:25.
The assets warming does not mean that they will be used, just that they are on stand-by if the operator does require the additional capacity this evening.
DFS’s fifth use in a month
This is the fifth time since the beginning of November when DFS was officially introduced that National Grid ESO has called on the service to help balance the grid.
It ran the first four tests on 15 November, 22 November, 30 November and 1 December. At 300MW per half an hour – up from 200MW for the first two tests and 250MW for the second two tests – this represents the heaviest use of the service.
There are now more than 25 providers of DFS, including some of the biggest domestic energy suppliers, such as British Gas, OVO and E.ON Next.
Octopus Energy has stated that it moved almost 450MWh of energy consumption across the first four demand flexibility periods, helping to save over £1 million collectively.
rom (GMT) |
To (GMT) |
DFS Required (MW) |
DFS Procured (MW) |
DFS Provider Bids Accepted Total Cost (£) |
17:00 |
17:30 |
300 |
149 |
223497.15 |
17:30 |
18:00 |
300 |
155.36 |
233035.12 |
18:00 |
18:30 |
300 |
154.73 |
232100.08 |
18:30 |
19:00 |
300 |
150.69 |
226028.98 |