National Grid procures a range of balancing services from large electricity consumers that are able to interrupt their load, or run backup generators, to help us balance the electricity system in Great Britain. These consumers are generally known as “Demand-side providers” and are typically industrial or commercial sites of a few megawatts or more. The information on this page is intended to give potential new providers a very broad overview of the opportunities available to provide commercial balancing services to National Grid. For further details please refer to the Services page.
Frequency Response
National Grid procures frequency response services, to keep the electricity system frequency close to 50Hz on a second by second basis, by automatically altering the production or consumption of electricity in real time. A typical demand side provider of frequency response services would have electricity load that could be shed instantaneously and automatically in the event of a significant variation in system frequency. Trigger levels are set to statistically manage how many times per year this is likely to happen.
Fast Reserve
National Grid procures fast reserve to meet large, rapid rates of change of demand for which conventional power stations are too slow to respond. A typical demand side provider of fast reserve would be very large (e.g. tens of megawatts) and, upon receipt of an electronic instruction from National Grid, would be able to start backup generation and/or reduce demand very quickly (e.g. within a couple of minutes) and run for a short period.
Short Term Operating Reserve (STOR)
National Grid procures STOR during defined times of the day, in order to have reserves available to cater for general variations in demand and generation failures. A typical demand side provider of STOR would, upon receipt of an electronic instruction from National Grid, be able to start back up generation and/or reduce electricity demand within timescales of up to four hours, and be able to run for a couple of hours.
Constraint Management
National Grid procures Constraint Management Services to alleviate localised power flow constraints on the high voltage transmission network, for example during a planned network maintenance activity. A typical demand side provider would be able to, on a pre-planned basis, shutdown its demand or run backup generation continuously for a sustained period, e.g. a number of days. Occasionally the need for the service would only be for defined periods during the daytime.