National Grid said that the £2.4 million spent on balancing payments on the day in November when a  Notice of Inadequate System Margin (NISM) was issued was “not extraordinary”.

In a letter to House of Commons’ Energy & Climate Change Committee Chair Angus MacNeil, the grid operator said that it spent £1.05m on balancing actions during the NISM on 4 November and £1.35m on balancing actions outside the NISM on the same day.

Cordi O’Hara, Director, UK System Operator, at National Grid, wrote: “It is important to note that the costs of the balancing actions taken on the 4 November were not extraordinary, and for reference the average daily costs incurred for balancing the electricity transmission system throughout 2014-15 was £2.33m.”

MacNeil had written to National Grid requesting information on behalf of his committee.

43MW of demand-side response used

O’Hara said that all 43MW of the Demand-Side Balancing Reserve had been used for the first time during the NISM on 4 November.
About 400MW of Short Term Operating Reserve was used.

A further 200MW of trading also took place with Ireland.

> Read National Grid's letter