The National Grid has doubled the length of its annual emergency gas shortage drill from two to four days as the energy industry braces for supplies to potentially run out over the winter. Gas prices have rocketed in recent months amid the recovery from coronavirus lockdowns and as Russia has sought to use its control of gas supplies to Europe as leverage amid its economic and diplomatic isolation since its invasion of Ukraine. European benchmark natural gas prices ended Monday at a record high settlement price of €276.75 per MWh – 10 times the price a year ago. That has triggered a scramble by European governments to find alternative gas supplies and to try to fill up storage tanks. The UK’s business secretary, Kwasi Kwarteng, has not sought any advice from government officials on the possibility of rationing energy before the end of June, the BBC reported on Tuesday, citing data obtained under freedom of information laws. Kwarteng, who is likely to be the next chancellor if Liz Truss wins the Conservative leadership race, has also opposed the suggestion from civil servants that the public should be asked to cut their energy use, believing it is unnecessary for the UK and that energy use should be up to individuals. However, the gas supply industry is bound by law to run drills for gas shortages, including deciding which customers would have to cut their gas use. Under the UK’s practice exercise, the National Grid, a private company that looks after much of the UK’s energy supply system, will use mock demand data and simulate a series of supply losses. Industry will then receive notifications to test the communication systems, and National Grid will test gas distributors’ responses to a “gas supply shortage which has electricity system implications”, according to a briefing note from National Grid. “Exercise Degree” will take place on 13 and 14 September and 4 and 5 October 2022. Last year’s “Exercise Celsius” took place on 29 and 30 September 2021. Gas suppliers and National Grid are bound by law to prepare for a network gas supply emergency, when the gas pressure in the network falls to dangerously low levels. If an emergency is declared National Grid has the power to request additional gas supplies or to require consumers – starting with the largest industrial customers – to stop using gas. National Grid will try to maintain supplies “as long as possible” to households that rely on gas for cooking and heating. It also has “priority customers” whose supplies will be maintained until domestic gas supplies are threatened. These include hospitals and care homes, as well as lower-priority industry such as furnaces and glass works, who would sustain costly damage if gas supplies stopped. Concern about energy security has risen since a report was leaked to Bloomberg showing the government had prepared crisis plans modelling a situation where businesses and even consumers could face blackouts this winter. Under ministers’ latest “reasonable worst-case scenario”, officials believe the UK could experience blackouts for several days in January if cold weather combined with gas shortages to leave the country short of power. Instead of the suggestion of an information campaign encouraging the public to save energy, the government favours a plan put forward by National Grid to incentivise households with smart meters to save energy by paying them to use appliances at off-peak times. The Department for Business, Energy and Industrial Strategy was approached for comment.