Vampire devices are common electronics that drain power even while on standby – costing households a total of about £3.16bn every year.
This figure, according to research by British Gas, equates to £147 a year for the average household, the equivalent of roughly two months of electricity charges.
Examples of vampire devices included laptops, internet routers and smart speakers that are plugged in and switched on around the clock.
With a 54% rise in the energy price cap introduced in April – and another rise expected later in the year – households have been advised to switch off their vampire devices to limit the rise in bills.
According to the research, it costs £24.61 to keep a television on standby, while computers could cost around £11.22 a year.
Set-top boxes for televisions also cost £23.10 a year, while games consoles cost over £12 keeping on standby.
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Other prices include:
Washing machine: £4.73
Phone charger: £1.26
British Gas energy expert Marc Robson recommends plugging these devices into an extension lead that can easily switched off at night.
He said: "At night, or when not in use, try switching off devices at the mains rather than switching to standby, as even the standby light on a television uses energy.
"Try not to overcharge your mobile phone and laptop unnecessarily.
"As soon as your device is charged, try and get into the habit of unplugging it.
"Not only will this save energy but it also prolongs battery life.”
Robson also recommended using smart plugs, which can be used to check everything is off via smart phones.