Following on from the more detailed measurements of input current to some computing equipment and low-energy lamps, I felt like having a better idea of how much is wasted by several always-on appliances, as well as some `which should I use' loads such as microwave and conventional ovens.
Measurement by an oscilloscope, with current and voltage probes, is time-consuming compared to a simple plug-in power meter, although the simple meter gives no detail of the harmonic spectrum. Such a meter was used for the following measurements: its details are `Everflourish EMT707CTL ref:36.2897', and it has been tested against an oscilloscope measurement, from which it was found to calculate P and Q correctly, which is not always so for such meters (see the meters test in the it_power page).
Much of the remainder is in plain text form, as I keep such notes in this way and don't see much advantage to spending time making an html table.
The fridge and freezer were not included, due to poor accessibility of
their plugs and sockets, and to their intermittent nature (long-term
energy measurements would be needed, to find the duty cycle, if wanting
the mean consumption).
Based on sust-it.net,
`larder fridges' are about 140 -- 170 kWh/year.
and `upright freezers' about 220 -- 380 kWh/year.
So, total for our separate, tall, fridge and freezer may be from
about 40 to 60 W, mean combined power.
The consumption of elements on an electric cooker is easily found from manuals. Ours (Electrolux CF 161 B) takes from 1.0kW to 1.9kW for the hotplates, and about 1.8kW for the basic oven (top and bottom heaters, not the extra grilling element) when on full. When the rings are turned below the full setting, it's not obvious how linearly the reduction in duty cycle (proportion of time for which the element is on) relates to the number shown on the switch -- I've never tried testing this.
To get a rough idea of the warm-up energy and the steady-state power consumption of the oven, I timed its warm-up and the duty-cycle when at 200 degC.
Warming up from room temperature, empty:
time(mins) temp(degC)
0 20
5 100
7½ 150
10 200
On reaching 200 degC, the cycle of the empty oven was about 180s on and 400s off, i.e. on for about 0.3 of the time: the mean power consumption (mean heat loss) is therefore about 600W (when empty).
The following are a few more kitchen things whose consumption I measured:
Kettle (rated 2.5--3.0kW [220--240V]) on 2500W Coffee-percolator (small) on 430W Food mixer (no mechanical load) lowest 60W 68VA highest 96W 96VA Kitchen extractor fan I 29W 31VA II 31W 32VA III 55W 64VA Microwave oven (Philips Whirlpool VIP27, fairly old) 1000W-setting 1750W 1890VA
Clavinova CLP-130 (electronic piano-substitute) off 0W 0VA on 16W 28VA Stereo system (Technics SAX800L, integrated amp, tuner, cassette) off 0W 0VA on, radio 20W 28VA Cordless phone base-unit phone in place, idle 2W 13VA phone out, in use 2W 13VA Mobile-phone charger (Nokia, c.2007) without phone 0W 0VA Uniross battery charger (model CXH3: 4x(AA|C|D)) empty 2W 10VA charging (4x AA) 5W 14VA
VOIP phone adaptor box (for a Tele2 `internet telephony' account) running 4W 18VA Ethernet switch (Netgear gigabit 8-port switch) running 7W 16VA Wireless router (D-link DI 524: wireless[b|g] plus 4way hub) running 6W 18VA Laptop computer (Dell Latitude X200, 800MHz, with CPU scaling) adaptor alone 1W 10VA sitting idle 17W 42VA playing video (~80%CPU) 24W 55VA Laptop computer (Dell Latitude C840, P4mobile 1.8GHz, scaling) adaptor alone 1W 10VA sitting idle 40W 42VA playing video 60W 61VA Laptop computer (Toshiba Portege, 7100 series, ~450MHz) adaptor alone 2W 11VA sitting idle 31W 62VA full cpu 37W 72VA Desktop computer (AMD Duron CPU, 800MHz, 1 disk) sitting idle 66W 130VA full cpu 80W 150VA Desktop computer (Dell, with PIII 500MHz, 1 disk) off 2W 11VA sitting idle 33W 67VA Desktop computer (IBM-6569-NAG, PIII 800MHz, 1 disk) off 2W 11VA sitting idle 30W 61VA full cpu 53W 102VA Desktop [`Workstation'] computer (Sun Ultra60, 2CPU 450MHz, 2 disk) off 2W 21VA sitting idle 168W 186VA Laser printer (HP1018, a small b&w one) idle 3W 11VA starting job 570W during first page 360W Scanner (Epson Perfection 1670) adaptor alone 0W idle 11W 25VA Monitor (CRT: Sun GDM-5410 [Sony] 21") plain VGA console 85W `normal' 112W 118VA very black window 102W very white window 136W Monitor (CRT: Compaq MV720) on, computer off 6W 16VA `normal' 58W 96VA Monitor (CRT: Samsung SyncMaster 15 GLI) standby 4W 12VA `normal' 67W 150VA Monitor (LCD: Samsung Samtron 51S, small) off 1W 10VA on, computer off 1W 10VA `normal' 24W 48VA Computer speakers (Small Dell ones) off 2W on, inactive 2W on, active 3W 14VA Computer speakers (small, cheapo) off 1W 12VA on, inactive 2W 12VA Computer speakers (Harman Kardon, c.2000) off 2W 15VA on, inactive 4W 15VA on, active 4W 15VA
Page started: 2009-02-13
Last change: 2009-03-11