National Grid Electricity System Operator (ESO) is considering introducing a new demand flexibility service as part of contingency measures to ensure the security of power supplies over the coming winter.
The body has also set out conditions for the use of the coal plants that were previously scheduled to close by this autumn but have been contracted by the ESO to remain available over the winter to guard against electricity shortfalls.
The possibility of creating a new flexibility service was raised in a consultation on proposed changes to the annual statements the ESO is required to issue under condition C16 of its transmission licence.
Although it has already updated its licence statements for 2021/22, the ESO is conducting a further review in response to the war in Ukraine and the resulting risks to energy security in Europe due to the continent’s reliance on gas imports from Russia.
The consultation said the service would enable the ESO to utilise demand-side flexibility that is not currently available in real-time and enhance its ability to control output from providers that are not currently accessible through the Balancing Mechanism and its platform for ancillary services. The service would be procured through a pay-as-clear day-ahead tender process.
The document also reiterated that the ESO has concluded agreements with several coal power stations, which would have otherwise exited the market by September, to remain available over the winter.
The agreements had already been announced for two 660MW units at Drax’s power station in North Yorkshire and two 500MW units at EDF’s West Burton A plant in Nottinghamshire.
The ESO said these units will only be available for dispatch by itself and will not be able on the open market.
One of the proposed licence statements accompanying the consultation elaborated that these units will normally be dispatched once “all valid and feasible bids and offers have been accepted in the Balancing Mechanism”. It said, where possible, this will happen prior the triggering of the emergency demand control measures set out in the Grid Code.
The statement said in “certain exceptional circumstances”, these units may need to be dispatched before all valid and feasible offers have been accepted. It said these circumstances could include instances where system reserves and reactive reserves may otherwise be reduced below required levels or where no other plant with suitable dynamics is available.
It further clarified that the price of alternative actions available through the Balancing Mechanism will have “no bearing” on the ESO’s decision whether or not to dispatch the contracted coal units, which will instead be determined by prevailing conditions on the transmission system.
The deadline for responses to the consultation is 5 September.
According to reporting by Bloomberg on Tuesday (9 August), the government’s latest analysis of the energy situation over the coming winter found in a “reasonable worst-case scenario” Britain could face an electricity shortfall equating to around a sixth of total demand, even after the reserve coal units have been dispatched.
Quoting unnamed sources familiar with the government’s planning, the news outlet said this scenario, which could emerge in January if below-average temperatures coincide with reduced electricity imports from Norway and France, may require the UK to trigger emergency measures to conserve gas over a period of four days.