Can you really save £86/year by switching off the vampires?

DECC tells us we can save £86/year by switching off TVs, laptops and chargers when not in use.(See 5 energy myths that will shock your socks off #VampireEnergy.) That figure of £86 comes from a report called Powering the Nation based on data collected from 250 households in 2010/2011 - the Household Electricity Survey. Total household standby power was estimated in two ways, giving 47 W and 81 W. The higher figure - giving the £86 - was calculated by looking at how much households used overnight, then subtracting power for things like fridges and freezers that are active at that time. It includes not just chargers and TVs but also things like set top boxes, DVRs and computer network routers that you normally leave on all the time so they are always ready. Set top boxes can use up to 24W and routers often use 10W or more.

Laptop and phone chargers are rarely major standby hogs these days. Older chargers can be a problem - just feel the power supply and see if it is warm. If it is then it is taking power. In an earlier post (see Never mind your computer, watch your router (or your set top box)) I describe an experiment measuring standby for a variety of tablets, laptops and phone chargers - 11 in all. The total standby for all 11 appliances (fully charged) was 8W. Most households don't have even that many devices to charge.

Most people leave the DVR and set top boxes on all the time, partly to record things at odd times and partly so that the device can download updates overnight. I do know people who run theirs on a time switch that turns it off overnight. If they want to record something they have to remember to adjust the timer. Obviously, if you only turn things off overnight then you will only make a fraction of the savings. If you turn them off for 8 hours you would make about 1/3 the savings.

Sky boxes are notorious for high power consumption but they now have an eco mode which automatically sends the device to sleep overnight if it isn't needed. The only thing is, this feature is not enabled by default. You have to change the settings to enable it. I don't know about other types of satellite decoders - you could check your manual.

As for routers, well if you are insomniac like me and you have a wifi network then you can catch up on twitter in the small hours. Or you could turn the network off and read a book instead.