Boiling kettles to make tea for two when there is only one of you could cost an extra €50 a year in wasted electricity.
hat’s just one of the startling calculations made by energy experts as fuel bills continue to rise and calls for energy conservation grow.
Much focus has been placed on so-called “vampire devices” that keep draining power even when they appear to be off or on standby.
But an energy advisor says while there are savings to be made by switching off completely, the bigger problem is not ghostly appliances, but our ghastly habits.
That includes making tea for phantom guests.
“It’s such an ingrained behaviour,” says Katie Harrington, energy and climate awareness officer at Codema energy agency for the four Dublin local authorities.
“We’re constantly boiling full kettles for one person as if someone else is going to appear out of nowhere and need a cup.
“I worked it out that it would add €50 to my electricity bill in the year if I kept up that behaviour.
“And because it takes longer to boil a full kettle, you head upstairs, you do another task and then you come back down and you have to reboil it. It’s ridiculous really.”
For other easy, if modest, wins, those vampire devices are worth attention.
Lights on in empty rooms, TVs and satellite boxes left on standby, phones, games consoles, Fitbits and electric toothbrushes permanently on charge and laptops, PCs, printers and monitors in sleep mode all drain power.
Anything with a digital display, such as ovens, microwaves, coffee machines and digital clocks and radios do the same.
How much is hard to quantify. An old rule of thumb was that an appliance used 20pc of its electricity needs if it was not disconnected from the power, but that varies depending on its age and complexity.
Scary figures have circulated about satellite boxes but that includes times when they are left to record programmes so they are working away behind the blank screen.
But annual savings from €50 do seem possible if householders could get into the routine of switching off, especially in a very gadget-heavy home.
“We do recommend unplugging everything from the walls and not leaving them on when you’re not using them but honestly it’s nominal, particularly with newer devices,” Ms Harrington said.
“Space heating accounts for 60pc of the total energy use in our home and things like electrical appliances, hot water, lighting and cooking make up the remaining 40pc.
“So we need to look first at space heating. Turning down your thermostat by just one degree can save you 10pc on your energy bills.
“Do simple things like closing doors. Don’t heat the street, is what we always say.
“Of the 40pc, that isn’t space heating, the big energy users are anything else that creates heat – the cooker, electric shower, tumble dryer, dishwasher and the kettle.”
If you are still not convinced of the energy demons in a kettle, a Codema advice guide shows it uses as much energy making just one cup of tea twice a day as an average TV does running for 80 minutes, so boiling it for phantom companions makes no sense.
For other appliances, Ms Harrington says: “If you have an eco setting, use that. If you can get a night tariff and use an appliance then, do.”
Allowing layers of burned food and grease to accumulate in the oven, or frost to build up inside the freezer compartment, also uses more energy as appliances must work harder to do their job.
“Making sure the appliances you have are clean and working as efficiently as possible makes a difference.”