Office energy wastage calculator

Here is a quick way to estimate the power you will typically waste overnight and at the weekend in your offices when your devices are on standby...

Number you leave on standby overnight	Type of device	Approximate power wasted
	PCs (newish PCs with LCD monitors)	Watts
	PCs (newish PCs but with non LCD monitors)	Watts
	Very old PCs with manual, clunky power switches & old monitors	Watts
	Personal printers	Watts
	Network / workgroup printers	Watts
	Photocopiers	Watts
	Mobile phone chargers / other mains adapters	Watts
	Coffee machines (that have a built in tank of always-hot water)	Watts
	Non refrigerated / perishable vending machines	Watts
	Network routers etc that IT tell you you can switch off overnight	Watts
	Scanners	Watts
	Computer speakers	Watts
	Microwave ovens	Watts

Percentage of PCs left running overnight		%
Of those PCs not left running overnight, what percentage of PCs are shutdown, but not turned off at the plug overnight		%
How long is a typical working day		hours
Do these PCs etc get used "normally" at the weekend
BTW this means your computers are typically idle for this many hours per week
How much, on average, do you pay for your electricity		pence /kwh

Total power wasted when devices are idle		Watts
Total power wasted per year		kwh per year
Using Bye Bye Standby you could save up to		Kg of CO2 per year
... and up to £		per year

Assumptions

NB This model assumes the following:

Your office is pretty typical, with no strange power hungry devices except those listed
That you download and use the Bye Bye Standby PC Shutdown software (see download link)
There are roughly 4 million businesses in the UK (Federation of Small Business statistic) and each business has on average 1.5 PCS (a hopefully conservative estimate)
Devices such as telephones, burglar alarms, CCTV systems etc are left on all the time and Bye Bye Standby Energy Manager is not used to reduce their energy use