Learning how much our energy use costs is key to understanding how to use less and to saving money. To illustrate this, the table below shows how much it would cost to run a number of different appliances for set amounts of time.  You can, however, make these calculations yourself if you know how much a unit (kilo Watt hour- kWh) of electricity costs you. This information is displayed on your bill. You will also need to know what the power rating of your appliance is - usually displayed on a label on the appliance itself (on the back or underside), as well as a calculator.

 

 

Electric oil radiator  

2000 Watts (2kW)                      

 

 

 

 

 

            

Electric Sandwich Toaster

700-760 W (0.7-0.76kW)

 

 

 

 

 

 

If the label on your appliance says 2kW then it would use 2kWh’s if it was left on for an hour.  If the appliance is displayed in watts it is easy to convert to kW’s as there are 1000 watts in a kW – the formula is below.

 

Watts ÷ 1000 (to get kW) x minutes ÷ 60 = consumption.  Then multiply this by unit cost (eg.14p)

 

Using the radiator above as an example, running for 1.5 hours, the calculation would be:

 

2000 ÷ 1000 x 90 ÷ 60 = 3 x 14 = 42p.

 

So to run this radiator for 1.5 hours will cost 42p!  Over a week this would cost £2.94 and £11.76 over a month.

 

 

Examples of household appliances and how much it costs to run them...

 

Appliance

Duration

Units (kWh)

Approximate cost *

Dishwasher 1.05kW (new A rated appliance

1 full load (30
min quick
wash)

0.525

7.35p

Iron (1.3kW)

1 hour

1

18.2p

Kettle (3kW)

1.75 litres
boiled water

0.15

2.1p

Microwave oven (0.75kW)

0.5 hrs

0.375

5.25p

Electric grill (3.4kW)

Medium heat
for 0.5 hrs

1.7

23.8p

Radiant electric cooker ring (2kW)

1 hour

2

28p

Fridge

24 hours

1-2

14p-28p

Freezer

24 hours

2-3

28p-42p

Vacuum cleaner

1 hour

1-2

14p-28p

Games console (380w)

2 hours

0.380

5.3p

Heated under blanket (single)

1.5 hrs/night
for 7 days

1

14p

Wide screen TV

5.5 hours

1

14p

Tumble dryer

1 hour

3

42p

Washing machine 40°

1 hour

1

14p

Energy saving light bulb

50 hours

1

14p

Conventional light bulb (60w)

16 hours

1

14p

 

* 14p per kWh – not including standing charge