What does it cost to operate?

You want to determine the value of replacing an old appliance with a new one. For example, you have a refrigerator manufactured in 1984. Since you don't have a kWh meter, you look in the table below and get 1457 kWh/year for the average refrigerator sold that year in Canada. The new appliance has a label claiming it uses only 410kWh per year. The potential savings are 1457 - 410 = 1047 kWh per year.

The annual cost savings are 1047kWh * $0.10/kWh (your power rate) = $105

Assume the new refrigerator will last 15 years. Assume you can sell the new appliance 15 years from now for $100. Using a spreadsheet or financial calculator, you next determine the present value of saving $105 a year for 15 years and then selling it for $100. In Microsoft Excel, the formula would be =PV(0.07,15,105,100) and it will yield $993. The link below will also calculate this for you.

Appliance Savings Calculator with database lookup This means that spending $993 on this new refrigerator now will yield a return of 7%, which is the average growth of the stock market over the last 200 years. If you can get the refrigerator for $993 or less, then it is a good use of your investment dollars. If you pay more than this, then your money might have been better invested elsewhere.

The table below of actual values (as opposed to government averages) will grow as I have time to collect more data. The intent is to be able to make accurate economic decisions about appliance replacement.

Average appliance energy usage (from EnerGuide). These averages are good for general estimates of what an older appliance might use. See below for actual, real world measurements.

Annual kWh	1984	1990	1997	1999	2004	energy star
Fridge	1457	1044	664	664	465	411
Dishwasher	1213	1026	649	640	457	422
Clothes washer	1243	1218	930	860	573	267
Standard clothes dryer	1214	1103	887	908	912	413
Chest Freezers	813	658	342	337	344
Self cleaning Ranges	790	727	759	742	622

These are actual kWh readings from appliances. It is important to figure out what draws the power you pay for every month, so that you can make informed decisions about where to direct your efforts. Many devices are intermittent (like a refrigerator that cuts in and out) and seldom draw the "rated power" listed on the label, so determining usage requires electrical test equipment.

For simple devices like light bulbs, multiple the wattage times the hours of usage and divide by 1000 to get kWh. For example, a 60W bulb running for 10 hours burns (60W x 10hr)/1000 = 0.6kWh. For complicated things like dishwashers, computers or  refrigerators you need a kWh meter to monitor it over time. Since most people don't have a kWh meter, we started this reference list. Please feel free to contribute to it -- you can send us your measurements via the "contact us" form.

Name Model kWh Measurement Period Comments Picture Toaster Grocery store brand (President's choice) 0.03 Single use, white toast came out medium brown. 2 slice toaster Toaster Krupps 0.07 Single use, white toast came out medium brown Quartz element,  2 wide slots, capacity 4 slices Kettle Philips 0.09 Single use, boil 1 liter water until auto-shutoff   Deep Fat Fryer Grocery store brand (President's Choice) 0.30 Preheat then cook chicken strips for 8 minutes at 180°C / 350°F.   Clothing washer LG TROMM model WM1814CW circa 2005 0.08 Single wash Front loader, warm wash, cold rinse, high speed spin. Settings as pictured. Clothing washer Whirlpool model LXR7244JQ3 circa 2004 0.22 Single wash Top loading, regular cycle. Dish washer Kitchenaid Superba model KUDS01FLSS2 0.74 0.49 Single wash Smaller figure is for energy saver dry. Fridge Kitchenaid Superba model KSRA25ILSS0 3 mfg date 08/03 45 per month (based on 3 days of measurement) Room temp was 22C, no children!. Energuide 616kWh/year or 51kWh per month. Fridge Whirlpool model ET8WTMXKQ0 mfg date 02/04   Room temp 21C. EnergyGuide and EnerGuide labels estimates 482kWh per year or 40kWh per month. Fridge Danby mini-fridge model DAR452BL  circa 2002 17 per month (2 day measurement, door never opened) Room temp 21C. 343 kWh/year or 29 kWh/month. Fridge Danby wine cooler circa 2002 23 per month (1 day measurement) Room temp 21C, inside light off. Water cooler Oasis hot and cold, circa 2001 95 per month -- regular use with 3 people, cold water and tea - measured for 24 hours Room temp approx 20C. Boiler and chilling chamber are very close together. Heat exchaner Venmar Constructo heat exchanger 89 per month Draws 124W at 110 volts on high with an airflow of 150m3/hr. Internet Dlink ADSL modem, Dlink wireless N router, no-name 8 port switch (2008 vintage) 7.0 per month On 24*7. Older equipment probably draws twice this, especially if the transformers are bulky and run warm to the touch Security system DSC 1832 with zone expander, RS-232 interface, escort module. 7.6 per month Includes transformer losses. Security System DSC Power Serices, RS-232 interface 7.2 per month Includes transformer losses Generic tower PC Pentium 4, 2.6GHz, two 3.5 drives, all slots full. 84 per month. Observation period 8 hours with about 1 hour of active use. Does not include monitor power. On 24*7. No special power saving features. Circa 2005. PicoITX 1GHz CPU. Pico ITX form factor, 250G serial ATA. 12 per month On 24*7. Circa 2008. Runs Debian. Deep Freeze Deep Freeze Frigidaire model FF014F3AW0 manufactured May 2001 63 per month (based on 1 day of measurement) Door seldom opened. Room temperature 22C.