Licence changes are now being sought by Ofgem, aimed at raising standards for grid restoration services to the level of norms which already govern generators’ commitments for grid balancing.
Beis’s mandarins signalled in April their desire to strengthen rules affecting licenced generators, specifically in relation to sparking up supplies when one or more big plants falls offline.
Legally binding targets are now needed, Whitehall argues, for delivery and response to a major trip out on the National Electricity Transmission System.
The most serious recent national outage occurred in August 2019. Following in swift succession after a lightning strike, Ørsted’s Hornsea One wind farm and RWE’s Little Barford gas turbines jagged off the system.
Black Start recovery – the national system’s partial or complete restoration after an unplanned or catastrophic blackout – is receiving Whitehall’s renewed consideration. In May National Grid-ESO awarded eight new contracts for ESRS, or Electricity System Restoration Services.
As renewables disperse generation sources exponentially across the network, the ESO sees a possible second solution in securing advance pledges from smaller power makers, including those close to likely choke points. Such is the focus of the Grid’s world-leading Distributed ReStart project, running for three years until March 2022, and backed with £10.3 million from licensees.
Initially in April and then formally in July, Ofgem consulted on tighter clauses for restoration. Its modifications to supply licences now include:
- The energy secretary setting parameters against a background of the newly publicised ESRS
- Scrapping any Black Start strategy, replacing it with a duty on licensed suppliers to produce their own ESR assurance framework
- National Grid ESO required to submit an independent auditor’s report to Ofgem, outlining the Restoration Model’s input data, technical calculations and assumptions
- Expanding chapter 16 of the Electricity Transmission Licence, and consolidating within a single yearly renewal requirements to report on procurement of both balancing and restoration services and costs.