This article is part of the Yahoo series ‘Simple Ways To Save The Planet’
Even after you’ve switched off the telly, turned off the lights, and your washing machine has had its last cycle, your home is still burning what’s known as "phantom power".
Also known as "vampire energy", it’s mostly down to hi-tech appliances like laptops, games consoles and phones that are never fully turned off.
Making more of an effort to decease the amount of electricity we consume reduces our energy consumption and saves money. For example, if people worldwide switched to energy-efficient light bulbs, the world would save £88bn ($120bn) annually.
Watch: How to save money on a low income
According to environmentalist and sustainability expert Claire Bradbury, appliances that are left on standby – or even those that are switched off but remain plugged in – have residual energy demand and "quietly" drive our home carbon dioxide emissions up.
'Myth to be dispelled'
The key is to switch them off properly at the wall when they aren't being used.
Bradbury says: "Switching off at the wall doesn’t damage our appliances and is a myth that should be dispelled.
"We are used to keeping devices in standby or sleep mode so that they can leap back into action in seconds. During the working day, a laptop that can quickly restore our session obviously makes a lot of sense but we don’t necessarily need this functionality once we’ve clocked off for the day."
Bradbury recommends switching off the wi-fi at night, and using "power strips", with several appliances plugged in, to ensure everything goes off.
She says: "The best way to switch off appliances is to turn them off at the source (the wall socket). Using a power strip or board can help rewire our home habits – by using them, we only need to remember to turn one switch off rather than several.
"There are some home appliances like fridges and freezers which need a constant power source, but as part of our night time routine, we should be switching off the devices and appliances that aren’t necessary while we sleep."
The problem is partly down to the fact that while large appliances like washing machines are subject to strict rules, smaller appliances are not standardised.
The energy supply sector is the largest contributor to global greenhouse gas emissions, according to the UN, and powers about 35% of total emissions.
Households consume 29% of global energy and contribute to 21% of resultant CO2 emissions. The most energy in households is used for heating and cooling.
And the problem of failing to "switch off" properly is only set to get worse, with the number of internet- enabled devices increasing rapidly.
For example, according to Cisco internet report, there will be 5.3 billion total internet users (66% of global population) by 2023, up from 3.9 billion (51% of global population) in 2018.
Households need to learn to deal with such gadgets, says Bradbury. "Household electricity consumption is still on the incline; the number of gadgets – especially smart devices – available to us is increasing, driving the energy load upwards."
Using smart meters is a good way to monitor the impact of "phantom power", she argues.
"Smart meters give access to real-time electricity usage, so if these are available from your energy provider, take them up on it. Being able to see the [pounds and pennies] on a real time basis gives us a very tangible way to keep track.
"Plug-in energy usage meters can also help us track the electricity usage of particular appliances, while water meters and room thermostats can assist with usage/temperature control around the home."
But remembering to switch off properly is easy.
Bradbury says: ‘The type of behaviour change that we need in the home isn’t as scary as we might think; we’re really talking about subtle adaptations to our habits rather than any seismic lifestyle shift.’
Claire Bradbury has worked with some of the world’s leading thinkers on sustainability challenges, including the Household of His Royal Highness the Prince of Wales. Dwellbeing: Finding Home In The City is published by Flint Books (The History Press), £20
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