Jesus 'n Jim

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appliance electricity cost

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

Enter either Volts and Amps, VA, or Watts.

, used with PF.

(can be in 00:00:00 or any combination of 0 hours/hrs/hr 0 min/mins/minutes/mn 0 sec/secs 0 ms/milliseconds)

Result: 0.00 cost per month

Result: 0.00 cost per year

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).

$W=\mathrm{Volts\left(V\right)}×\mathrm{Amps\left(A\right)}$
$\mathrm{VA}=\mathrm{rmsVolts}×\frac{\mathrm{rmsAmps}}{\mathrm{PF}}=\frac{W}{\mathrm{PF}}$
$\mathrm{PF}=\frac{\mathrm{VA}}{W}$

Where PF is power factor. (rms is Root Mean Squared).

When measuring my computer, PF was 0.68. see article on VA vs. Watts.

$\mathrm{V\left(olts\right)}×\mathrm{A\left(amps\right)}=\mathrm{W\left(atts\right)}$

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:

$\frac{}{\mathrm{month}}=\frac{W×\mathrm{HoursOn}×31days×0.0816perkWH}{1000}$

or

$\frac{}{\mathrm{month}}=\frac{V×A×\mathrm{HoursOn}×31days×0.0816perkWH}{1000}$

or

$\frac{}{\mathrm{month}}=\frac{\frac{\mathrm{VA}}{\mathrm{PF}}×\mathrm{HoursOn}×31days×0.0816perkWH}{1000}=\frac{\frac{\mathrm{VA}}{0.68}×\mathrm{HoursOn}×31days×0.0816perkWH}{1000}$

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.

Appliances/Devices, their cost, and usage
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
\$0.44:print
\$8.71:sleep
\$5.23:print
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
regular desktop 430W 185W 12h7d/wk \$5.62 \$67.39
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
toaster 1600W 1600W 10min7d/wk \$0.67 \$8.09/yr
Toaster 900W (120VAC@7.5A) 900W 10min7d/wk \$0.38 \$4.55/yr
Mono Laser Workgroup Printer 800W 24W:standby, 600W:print, 300W:avg 8h5d/wk \$0.35:standby
\$8.67:print
\$4.34:avg
\$4.16/yr:standby
\$104.07/yr:print
\$52.04:avg
Color Laser Workgroup Printer 1200W 100W:standby, 600W:avg 8h5d/wk \$1.45:standby
\$8.67:avg
\$17.35/yr:standby
\$104.07/yr:avg