Companies in busy urban areas are facing serious power supply problems that could restrict their IT expansion plans.

Experts say that rapid growth in computer use in cities is placing a strain on the UK’s ageing electrical infrastructure.

Adding significant server capacity can be delayed for several months by problems securing sufficient power supply, while obtaining electricity for a major new data centre can involve hold-ups of months or even years.

The problem is especially severe in congested areas, such as London’s Docklands. Mike Tobin, chief executive at data centre provider Redbus Interhouse, says that the majority of Canary Wharf’s power infrastructure, for example, was designed to supply technology that is no longer used.

‘There is a limit to what is available,’ he said. ‘Even five years ago, no one thought blade servers would be around.

‘You used to have four servers in a rack, now there’s 40, 50, 60, 70 servers in a rack, each taking the same amount of power. It’s a massive strain.’

Each blade server requires the same energy as larger, older servers, and the data centre needs similar levels of electricity to cope with the heat generated.

And the issue is not limited to London. ‘We have the same problems in Manchester,’ said Andy Harding, managing director at ISP Internet Connections.

‘It has caused us massive problems. We were told that the power supply could meet our growth for two years, but it has only lasted six months.’

Bob Fuller, IT director at investment bank Dresdner Kleinwort Wasserstein, warns that regulations such as the Markets in Financial Instruments Directive (MiFID) will add to the demands on IT departments.

‘You may need twice as many servers and PCs, but Canary Wharf doesn’t have enough power for that,’ he said.

EDF Energy, the utility supplying the City area, says companies should give early warning of upcoming increases in demand.

‘Timing is always a critical factor to ensure that we can meet future incre ases in demand for supplies, and we always advise businesses to liaise with us early on when they know their power needs are going to increase,’ said an EDF Energy spokesman.

The UK’s gas and electricity regulator Ofgem says £5bn worth of extra investment will be spent on the national grid over the next five years.