Electricity Consumption of Domestic Appliances

Will Smith - Climate Change - Electricity Consumption of Common Domestic Appliances.

I measure the electricity consumption of household devices in my home and other devices I come across from time to time. I hope this information is useful to others. The devices are grouped acccording to where in the house they normally live.

Computer Room
Lounge / Living Room
Kitchen / White Goods
Miscellaneous

In summary, the highest power usages over 24 hours are as follows (only including the items I still have, some have been disposed of or were not in my house in the first place):

Device	Power Usage per 24h (in kWh)	Comment
Electric shower	2 to 3 estimated	Yet to work out how to measure this, but I think it's a lot.
Large PC, always on, media and internet server	2.42	Expensive but inevitable. It cannot 'hibernate' or 'standby' since it's regularly accessed by other machines over the network. Downloads and backups are scheduled for overnight so 24 hour operation is essential. Possible solutions are to get a later processor that supports dynamic CPU scaling and voltages, so it runs slower when not in use.
Combined Fridge / Freezer	0.80
Kettle	0.75
TV (21", analogue)	0.42	This could be reduced slightly by turning off at the plug when not in use. Standby power is only 5% of full power.
PVR (personal video recorder, hard disk based, in lounge)	0.41	Surprisingly high usage. Another always-on device. Can be scheduled to standby when not recording, but then tends to miss some recordings.
Wireless ADSL Router (always on)	0.29	Providing wireless and internet capability to several PCs in the house. Slow to boot up. Easier to leave on. Does get hot - perhaps not a good model.
20" Computer Monitor	0.27	But I could reduce this to 0.19kWh if I always turned it off manually not in use rather than relying on standby.
Washing Machine (assume 1 load every 3 days)	0.26	Less greedy than most people might expect.

Changes
Version 1.0 - 27 February 2005.
Version 1.1 - 28 February 2005. Added typical kettle usage stats.
Version 1.2 - 1 March 2005. Tidied up some 24 hour averaged power consumption stats.
Version 1.3 - 2 March 2005. Italics where it clarifies what's changed. Clarify where 24h total power is estimated, and where it's measured.
Version 1.4 - 22 March 2005. Added long term TV usage, listed items using most power.
Version 1.5 - 15 July 2006. Added new monitor, printer, iron.
Version 1.6 - 3 Jan 2007. Added new fridge.

Computer Room
Device and Usage	Power	Usage	Comments / Conclusion
Laptop Computer
(Acer Travelmate 290E, Celeron M @ 1.3GHz, 14” screen)
on, not charging, no disk activity, no cpu activity, display on medium, blue background	15W		brightest screen uses 4w more than dimmest
on, not charging, no disk activity, no cpu activity, display on dimmest, blue background	13W
on, not charging, no disk activity, no cpu activity, display on brightest, blue background	17W
on, not charging, no disk activity, no cpu activity, display on medium, white background	15W
on, not charging, no disk activity, no cpu activity, display on medium, black background	15W		dark background colours gives no benefit
on, not charging, no disk activity, no cpu activity, display on medium, blue background, screen blanked	10W		screen on uses 3w, normal 5w, bright 7w
on, not charging, no disk activity, heavy cpu activity, display on medium, blue background	25W		full cpu uses 10w more than quiet cpu
on, not charging, no disk activity, no cpu activity, display on medium, blue background, disk spun down	14W		hard disk uses 1w when on but idle,
on, not charging, heavy hdd activity, no cpu activity, display on medium, blue background	20W		and 6w when heavily used
on, not charging, no disk activity, no cpu activity, display on medium, blue background,cdrom playing music	21W		cdrom uses 6w when playing music
on, not charging, no disk activity, no cpu activity, display on medium, blue background, standby mode	3W		standby is quite efficient, considering it returns to active almost instantly
on, not charging, no disk activity, no cpu activity, display on medium, blue background, hibernate mode	3W		Hibernate still uses some power
On, charging, no disk activity, no cpu activity, display on medium, blue background. Just plugged in (76% charged).	47W		3x idle power when charging.

Small PC
(Aopen XC Cube EZ18, Athlon XP2500+, 1 Hard Disk, onboard graphics, Windows 2000)
Off (from main front switch, PSU switch still left on)	6W
On, monitor on, no cpu activity, no hard disk activity, 1.83 GHz (default)	71W
On, monitor on, no cpu activity, no hard disk activity, 1.1 GHz	62W		slowing down cpu using 'speedfan' can save 9w
On, monitor on, heavy cpu activity, no hard disk activity, 1.83 GHz	97W		fully active cpu uses additional 26w
Peak (booting)	100W
standby mode, S1 type (power on standby)	42W		standby still uses lots of power
standby mode, S3 type (suspend to ram)	7W		Much better standby – important to choose correct type in BIOS
hibernated	6W

Large PC
(Tower Case, used as Server, always on, Athlon XP2000+, 4 hard disks, low end graphics card, Linux)
On, no disk activity, no cpu activity, 1.67GHz	99W
On, heavy disk activity on 3 drives, no cpu activity, 1.67GHz	116W		Each hard disk uses additional ~5w when heavily seeking
On, no disk activity, heavy cpu activity, 1.67GHz	142W		fully active cpu uses additional 42w
On, no disk activity, no cpu activity, 1.67GHz, 3 of 4 hard disks powered down.	81W		Each hard disk uses approx 6w when spinning.
On, no disk activity, no cpu activity, 1.67GHz, CPU underclocked to 750MHz	94W		On idle, slowing the processor further can only save around 5w.
On, no disk activity, no cpu activity, 1.67GHz, 1 of 2 memory modules removed (512mb total, was 1Gb)	97W		Each memory modules uses ~2W
On, no disk activity, no cpu activity, 1.67GHz, geforce 4mx replaced with ati 9600pro	102W		Several different graphics cards have similar idle power requirements.
On, no disk activity, no cpu activity, 1.67GHz, geforce 4mx replaced with voodoo banshee	105W		Several different graphics cards have similar idle power requirements.
On, no disk activity, no cpu activity, 1.67GHz, several motherboard options (sound, firewire etc) turned off	99W		Turning off unessential motherboard options makes no difference.
Total power (measured over 88.5 hours continuous on, mainly idle)		8.91kWh
Average power (averaged over 88.5 hours, mainly idle)	101W
Total power usage in 24h (always on, mainly idle)		2.42kWh


LCD Monitor
(17”, Acer AL1714)
on, typical computer display	28W
on, mainly white pixels	28W
on, mainly black pixels	28W		dark background colours gives no benefit
on, standby mode initiated by computer	2W		important to set computer to power off screen, not just 'blank'
on, standby mode initiated by 'on/off' switch	2W		no better than leaving computer to initiate standby

LCD Monitor
(20”, Dell 2001FP)
turned off using switch on bottom right	0W
on, standby	4W		Mediocre standby power, much better to turn off manually.
on, typical screen image	48W
Total power usage in 24h (estimated, assuming 4h on, 20h standby)		0.27kWh	Would be reduced to 0.19kWh if I always turned it off manually.

Computer Speakers
(Including subwoofer, Sony SRS-D300)
on, no music	3W
on, moderate volume music	5W
on, moderate-loud music volume	7W
Total power (measured over 11h40, music for ~1 hour)		0.03kWh
Total power usage in 24h (based on average over 11h40)		0.06kWh

Wireless ADSL Router
(Linksys WAG54G)
Off, but transformer (power brick) plugged in	2W		Still usage from power brick.
Wireless disabled, no activity	10W
Wireless enabled, no wireless or ADSL traffic	11W		Wireless on uses 2w
Wireless enabled, wireless activity, ADSL activity	12W		Minimal additional power used when data is flowing
Total power usage in 24h (estimated)		0.29kWh

Ethernet Switch
(D-Link DES-1005D, 4 port, 100mbit/sec)
Standby mode – no network activity	3W
Heavy network activity	3W
Total power usage in 24h (estimated)		0.07kWh

Bubblejet A4 Printer / Scanner
(Epson Stylus CX6600)
Turned off at printer	0W
Standby mode	4W
Printing or scanning	14W
Total power usage in 24h (estimated)		0.10kWh	Almost never used, much better to turn it on when I need to use it.


Lounge / Living Room
Device and Usage	Power	Usage	Comments / Conclusion
Digital Freeview PVR
(Humax, model 8000T)
standby mode	7W
on, in main menu	17W		when on (hard disk is spinning) uses
watching tv (and therefore recording)	17W		additional 10w regardless of the activity
timeshifting (both reading and writing to hard disk)	17W
Total power usage in 24h (estimated)		0.41kWh

TV
(Traditional, Analogue, 21 inch)
on, typical viewing	58W
on, most pixels bright	68W		varies depending on amount of bright pixels
on, most pixels dim	50W
standby mode	5W

TV
(Traditional, Analogue, 21 inch, different model)
on, typical viewing	50W
standby mode	3W
Total power (over 78 hours, used day and evening, typical family of 3)		1.38kWh
Total power usage in 24h		0.42kWh

Electric Effect Fire
fire effect only	80W		Surprisingly high 'quiescent' power usage. Investigation leads to 2x40w non-energy-saving light bulbs.
fire effect + 1 heating element	1000W
fire effect + 2 heating elements	1880W		each heating element is ~900w


Kitchen / White Goods
Device and Usage	Power	Usage	Comments / Conclusion
Fridge Freezer
(typical, made around 1990)
everything off	0W
fridge light on	13W
one or both(?) coolers on	110W
Total power usage (measured over 92 hours)		3.40kWh
Average power consumption (averaged 3.40kWh in 92h)	37W
Total power usage in 24h		0.88kWh

Fridge Freezer
(Bexo, manufactured 2006)
Total power usage (over 67.75 hours)		2.27kWh
Average power consumption	33W
Total power usage in 24h		0.80kWh

Deep Chest Freezer
(Small, made around 1970)
standby mode	1W
Cooling mode, beginning	155W
Cooling mode, later	128W
Total power (measured over 21h30)		2.31kWh
Averaged power consumption (averaged over 21h30)	107W
Total power usage in 24h		2.58kWh

Tall Freezer
(made in 1980's, but leaking door seal)
Cooling power, typical	170W
Total power (19 hours 45)		1.54kWh
Averaged power consumption (averaged over 19h45)	78W
Total power usage in 24h		1.87kWh

Kettle
(typical domestic)
Off	0W
Peak	1900W
Sufficient water for 2 large mugs of tea.		0.09kWh
Total usage (typical domestic use, 3 people, over 57 hours)		1.78kWh
Averaged power consumption (averaged over 57 hours)	31W
Total power usage in 24h		0.75kWh

Sandwich Toaster
(2 toasties at same time)
Cooking	950W
Total usage (two toasties, 10 minutes)		0.09kWh
Averaged power consumption over 24h (assume used once every 2 days)	2W
Total power usage in 24h (assume used once every 2 days)		0.05kWh

Rice Cooker
(typical)
Cooking	495W
Total usage (1 cycle, 30 minutes)		0.43kWh

Washing Machine
(built ~1995)
Off	0W
Water pump only	15W
Heat water	2300W		Despite being connected to hot and cold water. Why?
Rotate drum	250W		But much of time is spent pausing, just brief bursts of this.
Heat water and rotate drum	2550W
Spin (low speed), initial peak	1100W
Spin (low speed), sustained	300W
Total power (1 cycle, 40°C, nonfast coloureds, no economy mode, full load, 1 hr 30)		1.06kWh
Averaged power over cycle	707W
Total power usage in 24h (assume 1 load every 3 days)		0.35kWh

Washing Machine
( built ~2001, Hoover Performa 1200)
Off	0W
Water pump only	5W
Heat water	1700W		Again, even if connected to hot water supply (gas, in my house), it does it's own heating (electricity, more expensive). Crazy.
Rotate drum	150W
Heat water and rotate drum	1850W
Spin (low speed), initial peak	600W
Spin (low speed), sustained	200W
Total power (1 cycle, 40°C, nonfast coloureds, no economy mode, full load, 1 hr 30)		0.78kWh
Averaged power over cycle	520W
Total power (1 cycle, 40°C, woolens, economy mode (cold wash), 0h50)		0.01kWh	Alternative cycle. Too cold - soap tablet did not dissolve.
Total power (1 cycle, 40°C, woolens, not economy mode, 0h50)		0.39kWh	Alternative cycle.
Total power usage in 24h (assume 1 'nonfast coloureds' load every 3 days, no economy setting,)		0.26kWh

Microwave
(700w stated output)
standby mode	0W
Full power (9/9)	1150W
Half power, emitter on times	1150W
Half power, emitter off times	40W

Iron
(deLonghi 1600W steam iron)
On, not heating	0W
On, heating	1584W
Total power (35 minutes ironing)		0.13kWh	Although irons are high powered, they aren't on much of the time, even when in use.
Total power usage in 24h (assume used 1 hour, once per week)		0.03kWh


Miscellaneous Items
Device and Usage	Power	Usage	Comments / Conclusion
Battery Charger
4xAA, 5 hour charge
No batteries inserted	0W
Charging	5W
Fully charged, trickle	3W

Mobile Phone Charger
(Nokia 3310)
Charged	1W
Charging	5W
Total usage (1 charge cycle, 3 hours, then unplugged)		0.01kWh
Total usage (1 charge cycle, 3 hours, then idle for 45 hours)		0.05kWh

This work is licensed under a Creative Commons License.

Will Smith - Climate Change - Electricity Consumption of Common Domestic Appliances.

Computer Room

Lounge / Living Room

Kitchen / White Goods

Miscellaneous Items