Households could be told to cut electricity usage to avoid widespread blackouts after the coldest December night in a decade.
A freezing fog is blanketing the UK as Arctic conditions have seen temperatures plummeting, with six inches of snow forecast in the coming days.
The dropping sun and wind levels - on top of the rising energy costs - mean energy supplies are on a knife edge.
Wednesday night saw the mercury topple to -8.2C in Benson, Oxfordshire, to -9.3C at Aonach Mor mountain in the Scottish Highlands, and -5C at Gatwick.
While a number of schools were forced to shut yesterday with 5cm of snow falling in Aboyne, Aberdeenshire, and at Althnaharra in the Highlands.
The National Grid is on standby to take "enhanced actions" to shore up power supplies this weekend as wind levels drop, reports the Daily Telegraph.
These potentially include a new scheme which could see households sign up to be paid to use less electricity - for example, turning off the washing machine.
A spokesman for the company told the newspaper: "Margins are expected to be tighter this week, particularly for the next few days. This is based on our current assessment and is subject to change.
"Our control room has a range of operational tools available to manage this. These actions also include our enhanced actions."
The National Grid forecasts that wind generation in Britain is set to fall to 2.9 gigawatts today and 1.1 GW on Sunday - putting the "spare capacity" below adequate levels.
Morgan Vine, head of policy at Independent Age, told the Daily Mail : "The prospect of blackouts affecting older people’s heating and electricity supply this winter is incredibly worrying.
"Not being able to put the lights on or keep warm enough could put many older people’s health at risk, increasing the chance of falls and making health conditions worse.
"Many older people rely on equipment that needs continuous power, have telephones connected to their broadband routers or use their TV or radio to stay connected."
Power cuts already struck in the West Country yesterday.
The cold snap has come in from the Trondheim fjords below the Artic Circle in Norway - hence the name 'the Troll from Trondheim'.
The Met Office has issued a number of severe weather warnings, including for snow and ice in Scotland until midday on Sunday.
There is also an ice warning in the east and North East of England until midday today, and one in the west until midday tomorrow.
A National Grid spokesperson declined to comment when contacted by the Mirror.
But they said "we remain cautiously confident there will be adequate supplies this winter" as per the Winter Outlook report.
