National Grid forecasts 5.5pc UK winter supply margin

OREANDA-NEWS. July 11, 2016. UK transmission system operator National Grid is forecasting a 5.5pc supply margin this winter, similar to its forecast for the previous winter.

National Grid procured 3.5GW of supplementary balancing reserve (SBR) for winter 2016-17 earlier this year and said that without this SBR capacity, the de-rated supply margin would have been 0.1pc.

Peak demand is expected to be 53.6GW this winter. SBR capacity is not available in the wholesale market but remains ready to run in case National Grid calls on it.

National Grid's weekly 52-week ahead surplus forecast sees margins tightest in the week starting 12 December at 1.76GW and the week starting 16 January at 1.78GW in the forecast, released yesterday. In early February, before SBR capacities were procured, National Grid was forecasting negative supply margins on 5-19 December and 9-16 January.

Higher levels of demand side management from customers at peak consumption periods and an increase in the output of generation connected to the distribution network meant peak demand did not reach forecast levels last year, National Grid said, leading it to revise its demand forecast for this winter. This does not include potential demand for exports from interconnectors to France, the Netherlands and Ireland.

Total maximum generation capacity, including volumes procured under SBR, will be 72.3GW. This does not include possible imports from interconnectors. De-rated capacity is 54.7GW.

Available coal generation capacity will be 4.7GW lower than last winter but this has been offset by higher gas and wind generation capacity, National Grid said.

National Grid expects average winter net imports of around 1.8GW, made up of 2.5GW of imports from France and the Netherlands and 0.75GW of exports to Ireland.

National Grid 52-week margin forecast 7 July MW