Household appliances use a varied amount of electricity, depending on their efficiency. Newer appliances are generally built to be more efficient, and the location at which the appliance is placed also affects how much power the appliance will use; most new appliances include information regarding their average usage rate. In most countries, the amount of electricity used is measured in kilowatt hours, with one kilowatt hour equaling about $0.06 US Dollars (USD). Large appliances, especially air conditioners, use the most power, with central air conditioning units averaging 2,000 kilowatts per year, while a newer, small refrigerator averages only 450 kilowatts each year.
Kilowatt Hours
In many countries, including the United States, China, the European countries, and Australia, electricity is measured in kilowatt hours; however, in India, a kilowatt hour is referred to as a "unit of energy." To figure how many kilowatts an appliance uses, take the wattage of the appliance, multiply it by the number of hours used, and divide by 1,000. For example, if a new refrigerator has a wattage of 300, multiplied by 730 hours, and divided by 1,000, it averages 219 kilowatt hours.
The price of a kilowatt hour varies in the US, depending on location and peak usage times, but on average, one kilowatt hour costs about $0.06 USD. Electric bills will usually state exactly how many cents are being charged per kilowatt hour, which can help determine the cost of running an appliance. Rates can be different depending upon location, and on the total energy usage per month.
Factors Affecting Power Consumption
The location of an appliance can affect how much electricity is used; for example, a clothes dryer in an open location like a garage, is likely to be somewhat less efficient than one located in a house because of the difference in temperature. Similarly, a water heater with improper insulation is likely to be less efficient and will use more electricity than a well-located and insulated water heater. Placing appliances in the correct locations can increase efficiency.
Another factor affecting electricity usage of an appliance is the age of the appliance. Refrigerators over forty years old, for example, typically produce higher power bills because they run less efficiently. If a refrigerator has been purchased within the last five years, it is more likely to be an energy efficient appliance, which usually represents significant savings.
Refrigerator and Freezers
The average freezer and refrigerator purchased before 1985 uses about 100 kilowatt hours per month; this means it costs approximately $6 USD a month to run an older refrigerator. A relatively small refrigerator purchased after the year 2000 only uses only about 37.5 kilowatt hours per month, representing a significant savings on power bills, while larger refrigerators will use more electricity.
Washing Machines and Dryers
Relatively new washing machines use about 360 kilowatt hours per year, and newer dryers use about 765 kilowatt hours per year. Top loading washing machines hold more water, which means the machine should require more power to run; however, because the machine is typically built to be more efficient than a front load washer, the power bill is about the same for either model.
Small Appliances
Small appliances or household electrics can often use a surprising number of kilowatt hours despite their size. A computer and monitor without sleep mode can use up over 400 kilowatt hours per year, and a standing fan may use twice that amount. Most televisions average 80 to 400 kilowatt hours per year, while a microwave oven uses 0.36 kilowatt hours every 15 minutes it is running.
Large Appliances
Large appliances, like air conditioners, are some of the worst consumers of electricity. Central air conditioning may use as much as 2,000 kilowatt hours per year, and sometimes more. Electric furnaces are the most expensive, however, using over 6,000 kilowatt hours per year. Tankless water heaters are known to be more efficient and less expensive than water heaters that use a storage tank.
How to Save Power
Most appliances today include a label stating the average efficiency rate, and of course, kilowatt usage can depend upon how much an appliance is used. With electricity supply sometimes being exceeded by demand in heavily populated areas, it makes sense to choose appliances that will use the least amount of electricity possible; when purchasing appliances, look for those with the highest efficiency rating. Keeping appliances clean, and turning off appliances when not in use, can result in less money paid to the electric company. Using batteries to run small appliances like alarm clocks can help reduce the amount of power used. Solar panels offer a natural alternative to man-made power, and may be less expensive over the long run.