The resilience of Britain’s technology infrastructure is under scrutiny because of fears of winter blackouts and the impact of the soaring cost of energy.

Data centre operators have asked for short-term priority for energy use should electricity be restricted, to ensure that critical services, from banking to public services, can keep running.

They will present their concerns to the Department for Culture Media & Sport at a meeting this month, to outline the potential risks.

Many data centre operators are already reporting energy use restrictions in Europe, where they are running services on an intermittent basis — eight hours on, four hours off — relying on back up power sources to stay online.

As the bedrock of the digital economy, organisations from hospitals to businesses rely on a continuous supply of energy to their data centres to keep their servers operational and cool around the clock.

According to the International Energy Agency, data centres around the world use about 200 to 250 terawatt-hours (TWh) of electricity a year — about 1 per cent of total demand.

Operators are increasingly stockpiling extra fuel in case they need to switch to back-up generators. At least one data centre company in London is making contingency plans to bring in diesel aboard barges up the Thames.

Critical central London facilities used by the City’s financial services are particularly vulnerable as they could require thousands of litres of diesel to keep them going, in the event they can no longer use the National Grid.

Tiny Haynes, data centre specialist at the research firm Gartner, said: “It’s going to be a quagmire when you want to be able to resupply areas around the Docklands with huge articulated lorries. It will snarl up the Blackwall Tunnel and data centres might go down, it’s a big issue.”

The Department for Digital, Culture, Media & Sport recently closed a consultation on UK data storage and infrastructure, which is due to report later this year.

It said that “the UK is now reliant on large-scale data storage and processing services for the delivery of our essential services and the functioning of our broader economy. This means that ensuring the continuity of service of data storage and processing infrastructure is of national interest.”

There is precedent for data centres dealing with emergency situations, such as the extreme weather seen in Texas last winter, but nothing on this scale. It is rare for data centres to run on their spare generators for extended periods.

Businesses will be trying to “get to the front of the queue” when it comes to receiving diesel supplies from the energy companies, according to Andy Lawrence, executive director of research at the Uptime Institute, which advises companies on their data infrastructure.

Even if they have access to fuel, the switch to generators increases the risk of technical problems. “There’s a lot of evidence that when you switch from grid to generator that issues are likely to occur. This could also wreak havoc with sustainability commitments,” he said.

The hot summer has been an added complication for data centres and some older facilities stopped working in high temperatures, including the largest NHS trust in London, Guy’s and St Thomas’, as well as an Oracle and a Google centre.

The capacity of the national grid is already under scrutiny in Ireland, where Amazon and Microsoft have scrapped plans to build new data centres because of the risk of overwhelming the country’s power supply.

Data infrastructure is not designated as “critical national infrastructure” (CNI), a recognition of the importance of a sector, its assets or its functions.

A government spokeswoman said that “prioritisation of support or guidance is not restricted to CNI sectors in the event of an emergency — requirements and practicalities also play a part in considerations. All factors are assessed based on the risk and potential implications for the event at hand.

“We aim to ensure data centres, government and other key stakeholders are appropriately prepared for a range of possible scenarios that might affect the sector in both the near and long-term.”

Nick Winser, the national infrastructure commissioner, who looks at the country’s major infrastructure requirements, said: “Where feasible we should be finding ways of accommodating data centres, given the cybersecurity and economic benefits of having them based on UK soil.

“This means that distribution network operators should be engaging in early conversations with local authorities, regulators and industry about likely future needs, to enable anticipatory investments to strengthen the local grid where necessary.

“It’s pretty clear that’s not yet happening consistently, and with sufficient foresight.”