In the popular press there have been a number of reports along the lines of “households wasting hundred of dollars on standby power”. Being an inquisitive sort of fellow, I bought a simple power measurement meter to see how much money was being wasted in our home.
After some time measuring all the electrical appliances in our home, I sent the following letter to the editor of “Silicon Chip” magazine and it was published in the November 2011 edition:
It has been an interesting exercise to tabulate the various consumption figures of all our devices when they are on and off. I then made up a quick spreadsheet so I could see the annual costs rise and fall as I changed the usage time.
The surprising discovery in all this has been how little power modern appliances seem to use on standby. The following costs are based on 24 hour connection and 24 cents/kWh.
| 32″ LCD TV | 0.4 watts | $0.84 per year |
| STB/PVR | 1.1 watts | $2.31 per year |
| DVD player | 0.5 watts | $1.05 per year |
| 22″ LCD Monitor | 0.7 watts | $1.47 per year |
These figures seem to line up with what I believe is the European standard which requires a standby power usage of less than 1 watt to be considered “green”.
Some of the older appliances used more power on standby:
| Masthead amp | 3.2 watts | $6.73 per year |
| CRT TV | 5 watts | $10.51 per year |
| VCR | 6 watts | $12.61 per year |
| modem/router | 5.5 watts | $11.56 per year |
| Mircowave | 3.1 watts | $6.52 per year |
Even at these figures, you would need several old TVs and VCRs to make up the hundreds of dollars the popular media tell us we are wasting with standby power each year. Certainly turning off computers, CRT monitors/TVs and VCRs when not in use can reduce the power bill a bit. Of course turning off 3 x 50 watt downlights for an hour, or a 2400 watt heater for 4 minutes, will save more than leaving the VCR in standby for 24 hours – and you wouldn’t need to reset the clock.
The other thing I observed is a useful rule of thumb formula. At 24cent/kWh (the cost according to the bill I got last week), it is simply a matter of doubling the standby watts, to give you the cost per year. For example, a TV with a standby power of 5 watts, will cost just over $10.
The point being, modern appliances do not draw much power when on “standby” (turned off but still connected to the power). Older appliances do use slightly more power on standby, but you would need a lot of them to make up the “hundreds of dollars” often mentioned.
Of course, even little amounts do add up, so if you are not using something every day, you will save power by turning it off at the power point on the wall (or the switch on a power board) .
However if your TV and DVD player are made in the last few years, it will only cost you a few dollars a year if you leave them in “standby” while not being used. For this price is it not worth the effort I’ve seen people go through to reach in behind their entertainment system and flick the power switch off each night.
I find it much easier to turn off lights and appliances (like heaters and air conditioners) when no one is the room, and this does save power. In the last quarter alone, our electricity bill dropped by $160 by using electrical things less – and my entertainment system is still turned on.
If interested, you can easily calculate your own power usage for each appliance with the Power Usage Calculator.
