Grid issues power supply alert in Britain

LONDON: The UK’S electricity network operator has issued a warning that its buffer of spare capacity will narrow, flagging that the grid is struggling to match demand with enough supply.

While National Grid Plc said it was confident that power margins would be sufficient, the measure was narrow enough to trigger the automatic alert to the market.

The warning was later cancelled but it showed the impact a decline in wind generation would have as temperatures plunge this winter.

The grid had already planned to pay some homes to reduce consumption as demand rises, in a trial run of its new demand flexibility service.

The nation is going into the coldest months of the year with its tightest supply buffer for seven years, and National Grid has modelled the risk of power cuts in the event of a gas shortage that would restrict supplies to power stations.

That’s prompted it to pay to utilities hundreds of millions of pounds to extend operations at highly polluting coal plants that were due to shut permanently this year.

“This is the first tight day of the winter but it is not super tight,” said Phil Hewitt, director at consultant Enappsys Ltd.

“It is a small appetiser of tightness, there will be much tighter days ahead.”

A cold spell has hit the UK this week with colder-than-normal temperatures, forecaster Maxar Technologies LLC said in a report.

Minimum temperatures will be as low as three degrees celsius in London on Tuesday, which will drive up gas and power demand before temperatures rise again next week.

Thousands of households with smart meters have been signed up to participate in the demand reduction programme.

As much as about 140 megawatts of demand will be cut by people lowering their consumption in the early evening, according to a system notice. Wind power output was as low as 3,958 megawatts around noon on Tuesday, compared with more than 10,000 megawatts a day earlier.

While French nuclear availability held steady at 54% on Tuesday, utility Electricite de France SA extended four outages, further squeezing power supply in the region.