And one thing's for sure - at half-time, millions of people in the UK will heave themselves up from their sofas, amble into the kitchen and switch on the kettle for that great British pick-me-up - tea.

This mass synchronised tea-break has in the past caused huge power surges and problems for the National Grid, which operates the high-voltage transmission network in England and Wales.

A crack team of statisticians with their finger on the pulse of the TV sub-culture leaf through listings magazines in an attempt to predict peaks in electricity use.

They are trained to spot major crowd-pullers like Princess Diana's interview on Panorama or crucial episodes of soaps like Coronation Street or Eastenders. The Grid can then prepare for a surge - known in the trade as a "TV pick-up" - when the programme ends or during a commercial break.

The 1990 World Cup England v Germany semi-final sucked up a record-breaking 2,800 megawatts - a rise of 11% - after a penalty shoot-out. That amounts to around a million kettles switched on at once, as each appliance draws up to three kilowatts of electricity.

This year, the Grid predicts a 700-mw power surge at half-time during the first match of the most hyped World Cup ever - Brazil v Scotland - on June 10. But forecasts will be revised throughout the event.

Taking the tea strain

Being prepared is all very well, but how will the Grid cope with demand from this nation of tea-drinkers?

"Electricity can't be stored, it has to be made instantly," explained National Grid spokesperson, Diane Owen. "So the National Grid instructs power stations to lower generation prior to the surge. As the surge happens, they can raise their output."

The National Grid can also draw on the resources of fast-response pumped power stations like Dinorwig in North Wales. It can generate up to 1,200mw in 10 seconds.

The World Cup host country, France, is unlikely to suffer what seems to be a very English problem. "The French probably have a glass of wine instead," said Ms Owen.

Hi-tech solution on trial

In an effort to prevent black-outs during tea-induced power surges, some electricity companies are testing a new system which in theory could counteract the rise in demand by switching off other appliances in people's homes.

The PowerNet system from Remote Metering Systems (RMS) based in Hampshire can send on/off signals to domestic appliances via the mains electricity supply, according to the New Scientist magazine.

The signal rides on the back of the AC current, allowing the electricity company to turn an appliance fitted with a suitable modem on or off remotely.

Scottish Hydro-Electric has already installed 500 meters made by RMS as part of a trial which will eventually involve 2,000 customers, the magazine said.

The meters can switch off storage heating systems to control surges in demand and be read remotely, sending their data back along the power lines.

South Western Electricity was also said to be conducting trials of the RMS system.