Reactive energy (or reactive power) is crucial for maintaining the stability and efficiency of the power grid. Unlike active power, which does the actual work of running appliances and machinery, reactive power is used to manage voltage levels within the system. The National Grid ESO oversees reactive power services, instructing generators or other asset owners to either absorb or generate reactive power as needed.

For the purposes of the Code, subject to paragraph 1.1.3, the quantities of Active Energy and, where relevant, Reactive Energy Exported or Imported by any Party at a Boundary Point or flowing between Systems at a Systems Connection Point shall be measured and recorded through CVA Metering Equipment and/or SVA Metering Equipment installed, commissioned, operated and maintained and otherwise provided for as set out in this Section L.

BSC defined definition

Means the integral with respect to time of Reactive Power; and for the purposes of the Code, is comprised of Active Export Related Reactive Energy and Active Import Related Reactive Energy.

BSC documentation

• BSC Section L: Metering
• Code of Practice 1: The Metering of Circuits with a Rated Capacity Exceeding 100 MVA for Settlement Purposes

Further information

• National Grid website: About reactive power services