Homeowners could significantly slash their bills with a device that displays up-to-the-minute energy consumption, a new study suggests.

A team from Edinburgh Napier University tracked the amount of power used in 65 housing association homes that had been fitted with an Ewgeco real-time energy monitor.

The results of the six-month trial showed homes fitted with the Scottish firm’s device used up to 20% less gas than other households in the study.

This news comes as official figures published yesterday showed that skyrocketing bills forced 1m more UK households into fuel poverty in the space of a year.

"Our findings demonstrate that in-house utility displays can offer a tangible means of energy reduction by enabling behavioural change,” said study author John Currie, Director of the Scottish Energy Centre at Edinburgh Napier University.

The monitor’s simple traffic light display uses green, amber and red colours to highlight low, medium or high energy usage.

It works with ordinary utility meters to give instantaneous information on their gas, energy and water consumption.

43 homes in the trial, funded by the UK’s Technology Strategy Board, had the Ewgeco monitor clearly on display, while it was hidden in the other homes.

Researchers found that households that could see and use the energy-saving device consumed up to 20% less gas and 7% less electricity compared to those with a hidden monitor.

In interviews, around 94% of tenants said the device made them more aware of the energy they were using, while 73% felt it made them use less energy.

One study participant, a single mum with two children of primary school age, found it difficult to understand her bills and keep track of her spending until she discovered the Ewgeco’s daily target alarm app.

“When I get back from work and the kids arrive back from school everything gets turned on and sometimes left on unattended for hours,” she said. “The alarm means we can now budget our energy use to how much I can actually afford every day.”

The study was the first of its kind in the UK.

Mr Currie said: “With the introduction of smart metering technologies in all homes in the UK by 2020, it is imperative that such devices be linked with easy-to-understand interactive user-displays if national energy reduction targets are to be realised and not just seen as a means of providing utility suppliers with demand information."

The real-time energy monitor was devised by Perth entrepreneur Tanya Ewing, who was named British Female Inventor of the Year in 2008.

The former housewife, who was inspired to come up with the invention after receiving a particularly high gas bill, said: “Having won multiple awards for what originally was a good idea, it is very rewarding to read this report and see the proof that Ewgeco does what it’s meant to do – save money and energy in an intuitive way without changing your lifestyle.”

Dunedin Canmore Housing Association, Perthshire Housing Association and Glen Housing participated in the trial.

“This study indicates that the Ewgeco monitors have been helping our tenants to become more aware of their energy usage which has helped them to save energy and reduce their utility bills: this is great news, especially in the current climate where utility costs are set to increase significantly next month,” said Susan Napier, Dunedin Canmore Housing Association’s Business Development Director.