UK Sees Wider Power Buffer This Winter Despite Tighter Gas Flow

(Bloomberg) -- The UK is expected to have a bigger buffer of power generation to guard against shortages this winter, but the availability of natural gas is due to tighten. 

The National Energy System Operator expects margins of spare electricity capacity to be 10%, supported by an increase in batteries connected to the grid, higher availability of gas-fired generation and the addition of a power link to Ireland, according to a report published Thursday. Still, it comes as gas supply margins — the nation’s ability to cover peak demand for the fuel — will be tighter than in the last four years, network operator National Gas Transmission said in a separate document.

Fuel flows are being impacted by a continuing decline in UK North Sea output, which is only being partially compensated by strong imports of liquefied natural gas. Storage levels could also be lower given that the biggest facility, Rough, hasn’t had injections this summer. National Gas Transmission said the UK should have enough gas to meet peak demand this winter despite the lower supply levels.

Gas plants are often an important part of the UK’s power mix, especially on cold days where wind and solar levels drop off. If gas demand surges, the extra cost of running the plants could cause prices to spike on the wholesale power market. This eventually feeds through to consumer energy bills.

For electricity supplies, the margins are 900 megawatts higher than last year. NESO said there “may still be tight days that require us to use our standard operating tools, including system notices.”

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