the information you enter here runs only on your browser on your machine, no data is transmitted to a server unless you use bookmark URL button, then it submits to same page (nothing active on server side) and builds a URL. the equations for PF,W,VA are on rapidtables.com and are used by permission. I found out my equations for that were incorrect as of 2/2014.
Appliance Cost Calculator Application
Note: appliances with cooling or heating will only be on a percentage of the time, probably 20%-50%. so you can halve the cost or the time.
VA is not Watts(W).
Where PF is power factor. (rms is Root Mean Squared).
When measuring my computer, PF was 0.68. see article on VA vs. Watts.
Using the Kill-A-Watt EZ or PS 10 power WattMeter is a good way to get the real wattage used.
feed it into your calculator one of 2 ways:
See Clark PUD article on the equation. It's actually 120V not 115V, because I measured it. that was probably a typo or some accidental misinfo (or maybe it didn't get updated in years).
most plug-in appliances run on 120V (120VAC). clothes dryers & stoves: check your circuit breaker & multiply by 220V. your clothes washer 15A, dishwasher 20A, microwave 15A-20A, fridge probably run on 15A (check your breaker or back of fridge).
remember, this is worst-case cost.
found the equation on the PUD web site (cool!). hard to find.
There is also the P3 International Kill-A-Watt Power Usage Meter for $21-60. Also at Home Depot and Lowe's.
|device/appliance||power rating||power actually used||time on||$/mo||$/yr|
|An HP OfficeJet Pro 8500 Wireless a909g||120V@1800mA=1.8A=216W||120VAC@0.14A=16.8W:sleep 120V@0.58A=69.6W:print||23hrs55min7d/wk:sleep print:5min3d/wk||$0.73:sleep
|250W old 2004 xp desktop computer||250W||172W||12h7d/wk||$5.22||$62.65|
|160W old win98 computer||160W||47W||8h6d/wk||$0.82||$9.78|
|23" LED monitor||120VAC@2.1A=252W||50.4W||12h7d/wk||$2.04||$24.48|
|Logitech high-end speakers||200W||26W||24/7||$1.58||$18.94|
|top-end desktop PC with 3 video cards||960W||W||4h7d/wk||$||$|
|top-end desktop PC with 4 video cards||1200W||W||4h7d/wk||$||$|
|top-end desktop PC with 4 video cards||1500W||W||4h7d/wk||$||$|
|top-end desktop PC with 1 medium-high-end video card, multithreaded work||850W||135W||12h7d/wk||$4.10||$49.18|
|Cuisinart coffee pot||900W||120V@7A=840W||1-2h7d/wk||$4.25||$51/yr|
|1200W hair dryer||1200W||1200W:HI, 340W:LO, 62W:COOL||10min7d/wk||$0.51:HI, $0.14:LO, $0.03:COOL||$6.07/yr:HI, $1.72/yr:LO, $0.31/yr:COOL|
|1875W hair dryer||1875W||1405W:HI, 390W:LO||10min7d/wk||$0.59:HI, $0.16:LO||$7.11/yr:HI, $1.97/yr:LO|
|Mono Laser Workgroup Printer||800W||24W:standby, 600W:print, 300W:avg||8h5d/wk||$0.35:standby
|Color Laser Workgroup Printer||1200W||100W:standby, 600W:avg||8h5d/wk||$1.45:standby