FAQs
Below is a list of our most frequently asked questions. If you have a question that isn't listed below, please contact us.
What is a Capacity Market Notice and how is it triggered?
A Capacity Market Notice is a signal four hours in advance that, when taking into account additional operational reserve requirements, there may be less generation available than National Grid Electricity System Operator (ESO) expects to need to meet national electricity demand on the transmission system. The notices are intended to be a signal that the risk of a System Stress Event in the GB electricity network is higher than under normal circumstances.
Capacity Market Notices are communicated automatically by National Grid ESO systems to this website and will be issued at least four hours ahead of the stated commencement time. The primary trigger set by the UK Government for a Capacity Market Notice to be issued to the industry is where the level of available generation is within a 500MW threshold of National Grid ESO's requirement.
However, in certain situations, Capacity Market Notices can also be triggered in response to a Demand Control event. Where such events take place and a Capacity Market Notice is not already active, a discrete Capacity Market Notice shall be issued. The exception to this is when the event has been determined as occurring for system management reasons, in such circumstances a Capacity Market Notice will not be issued.
Related FAQs
- What is a Capacity Market Notice not?
- What is included within a Capacity Market Notice when it becomes active on the website?
- What is included within the Demand figure?
- What is included within the Aggregate BM figure?
- How should I respond to a Capacity Market Notice?
- What other information is available to the industry?
- How do Capacity Market Notices differ to System Warnings messages that appear on the Balancing Mechanism Reporting Service (BMRS)?
- Will a Capacity Market Notice always be followed up by an operational System Warnings message?
- Is the Capacity Market Notice actively updated following its initial communication?
- Can a Capacity Market Notice be cancelled?
- Can a Capacity Market Notice be issued for any period less than four hours away?
- If a Capacity Market Notice is cancelled can one be reinstated as active at a later time from the same time?
- How many Capacity Market Notices will be published each year?