Real Power Usage of Appliances (Wattage)

Do not estimate when you can measure.

Guessing can cost you money.

The Kill-A-Watt meter recorded the following results:

• The “1875W” hairdryer used only 1360W on high and 390W on low.
• The toaster-oven and coffee-maker were the next biggest loads, in the neighborhood of a kilowatt (kW), but, like the hairdryer's load, these are short duration uses. Brewing 4 cups (1/3 pot) took 5 minutes and the hot plate measured "zero" watts, so a 2-hour total recorded 0.16kWh.
• The “dorm” mini-cube refrigerator totaled about half a KWh in a day, similar to a constant 22W load but you need 10 times that power capacity because refrigerators are start-stop with a kick-start surge.
• I did not “benchmark” the computers to record their maximum loads. “Normal” was the spike of opening a program or application (browser, word processor) although other active use was sometimes 10-20W less. The desktop does not include the monitor.
• The "40W" fan used only 15W, close to only a third of its rating.
• The radio at maximum volume did not draw enough to register above zero on the meter (using an AC adapter to power the radio).
• The "Actual" numbers in the table are watts (W) observed on the meter, sometimes rounded up a few watts. The meter is less accurate near zero. Anything with an electronic remote control or a non-battery clock is using some power even when "off" (phantom load)--unless you use a "hard off" (for lack of a better term) such as a power-strip switch.

From IHB		Kill	-A-	Watt	Data
(c) 2007
Appliance	Rating (W)	Actual Peak High	Actual Start Boot	Actual Normal	Actual Idle Low	Actual Sleep ”Off”
Coffeemaker drip	1000	820	740	800	0	0
Laptop 150MHz	45	?	31	31	21	1
Laptop 2400MHz	90	?	85	60	25	3
Desktop 900MHz	?	?	60	55	35	2
Fan 4in 1-setting	40	15	NA	15	NA	0
Fan 20in 3-sett	?	170	NA	120	85	0
Hairdryer 2-sett	1875	1360	NA	NA	390	0
Monitor CRT 17in Energy Star	75	75	75	60	NA	0
Radio 2AA cell	?	0	0	0	0	0
Refrigerator 1.7cuft 1/25hp	?	215	215	80	?	0
Toasteroven	?	1150	1150	1100	?	0