Monday, March 26, 2012

How much electricity does a computer use and thus its cost to run?

When I reviewed the electricity usage of appliances around the house, one device which stood out in terms of electricity usage I must say I’d never really thought about.

I’d turn the computer on in the morning and leave it on all day. I work from home so for me having the computer on made sense. Often I’d even have a couple of computers on. The children even had their computers on as well. But the real surprise wasn’t when the computers we on, it was when they were off.

An off computer isn’t off. It is in standby and it keeps consuming power. The LCD screen looks off, but again it is in standby consuming more power than you’d think. Those additional devices such as the printer, the scanner, the external drive, all sitting there sipping away at the power and ready to immediately jump into action at your beck and call, even when you are asleep.

All those devices even when not used are in standby up to 24 hours a day in some cases (such as when you go away for the weekend) and all consuming power which is costing you real money.

Yet amazingly the answer is simple. When you power down your computer turn it off also at the switch on the wall. When you power off the devices at the wall you save power, you also prevent the situation of a brown out where the power drops and your computer ends up in an unknown state and doesn’t want to work and you also reduce the chance of a power spike taking out your computer during a storm.

Determining how much your computer is costing you when it is running and how much it is costing you when it is in standby is very easy. You can purchase a cheap power meter for under $30 and measure the power usage in watts. Then use the Electricity Cost Calculator I provide,  enter the power usage, the time the device is on, or the time it is in standby and the calculator will let you know the daily cost and the yearly cost. If you use your electricity retailers tariff you’ll get an even better idea.

I’d highly recommend that everyone should measure how much the devices in their home are using. We’ve reduced our daily electricity usage to around 6.5kWh down from around 12-14kWh per day. From what I’ve read the average power usage for a home is around 18kWh. We now save around $400 to $600 a year off our electricity bill and it all started with the purchase of a low cost power meter. We’ve added a couple of convenient foot switches and one remote control power switch (all quite low cost), some simple changes to how we turn devices off and the impact on our power bill has been significant. I know I prefer the $400-$600 in my pocket than the power company’s.

I wrote the Electricity Cost Calculator to help me when selecting high cost energy efficient lights compared to the lower cost normal lights. The calculator helped me make better purchasing decisions. I found the Electricity Cost Calculator was also very handy for working out the cost of appliances we had running in the home which helped me make informed cost saving decisions. I’d found the government and media would focus my attention on what they wanted (such as installing solar panels for their carbon certificate scheme) where I could achieve the same or better result with almost no cost.

Kelvin Eldridge

Call 0415 910 703 if your require computer assistance.
Covering Doncaster, Templestowe, Eltham and the surrounding area.

No comments: