They have designed prototypes that will undergo a comprehensive test regime in the university's iS-pace department before mass production. Each of the plugs will be fitted with a transmitter that sends signals to a central receiver where the householder can monitor use and waste from every appliance. The monitor can detect when appliances are left on unnecessarily and beam instructions to switch them off.

Homeowners will be able to override decisions by the monitor to switch off equipment. Researchers are confident in the gadget's potential -- they believe it should be fitted as standard to all domestic appliances within a few years.

"Homeowners will be able to see how much power every single device uses," said John Woods, a researcher. "You will be able to see if a fridge has failed, or if something has been left on that should not have been. It empowers people to make a real difference."

The plug is being developed with a $178,217 award from the Carbon Connections Development Fund to reduce domestic energy consumption, which is responsible for a third of all the electricity used in Britain.