Electronics Energy Guide

Managing Energy Usage

The single, biggest factor in every electric bill: the amount of electricity you use.

Common Electronics and Typical Wattages

Below is a table of common household electronics and typical wattages along with examples of estimated costs. This is just to give you an idea — your usage and costs will vary based on the actual wattages of your devices, their conditions and your family’s energy habits.

  Wattage Hours Used per Month Est. Cost per Month

Home Comfort

     
Air cleaner/filter 50 730  $ 7.67
Air Conditioner - Central (3-ton SEER 10)  
3500 158 $ 116.13
Air Conditioner - Room  1000 100  $ 21.00
Dehumidifier 500 135 $ 14.18
Electric blanket
300  240  $ 15.12
Fan - Ceiling
75 75 $ 1.18
Fan - Whole house
500 360 $ 37.80
Fan - Window 150 286 $ 9.01
Space heater 1320 49 $ 13.58
Water heater (40 gal) 4500 33 $ 31.19

Kitchen

     
Coffee maker 1000 10 $ 2.10
Range w/ oven 3000 $ 3.78 
Dishwasher 1400 18 $ 5.29
Microwave 1100 6 $ 1.39
Toaster oven 1051 3 $ 0.66
Refrigerator (frost-free, 16 cf.) 200 730 $ 30.66

Entertainment

     
TV (Digital, HD, >40") 200 149 $ 6.26
TV (Digital, HD, <40") 100 149 $ 3.13
Video game system 36 34 $ 0.26
Cable box 35 538  $ 3.95
DVR 17 60 $ 0.21

Home Office

     
Computer - desktop 100  152  $ 2.56 
Computer - laptop 60 122 $ 1.54
Mobile device charger 5 90 $ 0.09

Lighting

     
CFL bulb (60W equivalent) 13  90  $ 0.25
Incandescent bulb 60 90 $ 1.13
LED bulb (60W equivalent) 10 90 $ 0.19

Laundry/Cleaning

     
Clothes dryer 2790 24 $ 14.06
Clothes washer  255 18 $ 0.96
Hair dryer  710 $ 0.45 
Iron  1100 $ 0.69 
Vacuum cleaner 1400 3 $ 0.88

Outdoors

     
Pool pump 2500 132 $ 69.30

Your costs may vary based on factors including the number, wattage and age of your electronics, household size and your usage habits.


What goes into an electric bill? Watts. 

The typical home has dozens of electronics, each with their own power needs. The electric meter records all of the power they use over time, measured in kilowatt-hours (kWh), and that’s used to calculate your bill.

Ok, what’s a kilowatt-hour? It’s actually pretty simple: 1,000 (kilo) Watts used for one hour.

1 kWh =

  • One 1000W appliance used for one hour
  • Ten 100W bulbs used for one hour

Controlling Costs

Once you buy an electronic device, there’s another cost: the energy you buy every time you turn it on. These are the keys to buying less:

  • Conservation - turn off lights and electronics when not in use
  • Efficiency - choose lighting and electronics that require less energy to operate

 
Just like an old car uses more gasoline, an old appliance uses more electricity. But new appliances can vary a lot in their energy needs. An ENERGY STAR® clothes washer uses 25% less energy and about 33% less water than a standard model. Be sure to check the EnergyGuide labels found on most appliances to compare the estimated energy costs. When you choose an energy efficient appliance or device, you’ll benefit from savings for years to come.


Estimating Energy Use

Here’s a simple formula for determining the monthly energy use of an electronic device:

Wattage x Hours used per month = __ kWh
1000

Example:
The LED equivalent of a 100W incandescent bulb uses only 18 watts. If it’s on for three hours a day over a month, it will use 1.6 kWh. The 100W bulb would use 9 kWh. That’s over 80% more energy for the same amount of light!

18W x 90 = 1.6 kWh
1000


Estimating Energy Cost

To estimate the monthly cost of a device, simply add one more factor to the formula above:

Wattage x Hours used per month x Price per kWh = __ Approx. cost
1000

Below is the approximate monthly cost for that same 18W LED bulb mentioned above. This example uses 21 cents per kWh, but you can figure out your own price by simply dividing your last bill amount by the number of kWh you were billed for.

18W x 90 x $0.21 = 34 cents
1000

The 100W bulb would cost $1.89. That’s a savings of almost $19 a year simply by changing one light bulb. Imagine the savings from an energy efficient refrigerator