Use this basic calculator to calculate the cost of appliances

Kw/hr rate $ Size Appliance (w)    no. of hours 

     (1kw =1000w )     


Energy Cost Calculator  How to Save Energy  Appliance Running Costs

Appliance running costs                    



 Fan heater
 Two Bar Heater

Typical loading

2,400 watts
2,400 watts
2,500 watts

Approximate cost at 18 cents per kWh



Coffee Maker

      750 watts


Crock Pot

      230 watts



      2,000 watts


Food Processor

      375 watts



      200 watts



      1,240 watts



      2,400 watts

2c for one boiling

Microwave Oven

      750 watts

13c/roast dinner


      1,900 watts

35c/roast dinner

 Range Hood

     150 watts



      700 watts



     1,400 watts

1c/ slice






 Light Bulb

 - Single tube
 - Double tube


40 watts

40 watts
80 watts

3c for 4 hours
5c for 4 hours
7c for 4 hours

8c for 11 hours
16c for 11 hours

 Washing Machine

1,400 watts
1,400 watts
2,000 watts


17c/large load


Other Appliances



 Computer and    Monitor

200 watts


 Electric blanket

100 watts


 Extraction fan

40 watts

8c for 12 hours


1,600 watts


 Fax Machine




8 watts



15 watts


 Spa Pool

6,000 watts



85 watts

6c for 4 hours


81 watts

6c for 4 hours

 Vacuum Cleaner

1,100 watts


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Save Energy at Your Household!

There are many ways to save energy. As mentioned, much of the power we generate is wasted. A piece of coal may have 1000KJ of energy. This may be turned in 400KJ of electrical energy may be generated. 10-20% is lost getting to your house. The electrical is then turned into heating. So 1000KJ of original heat energy is turned into 340J of heat energy at the other end. So using energy wisely has a large impact on pollution associated with power generation.

Heat Loss
There are two primary ways that heat escapes buildings. Heat Transfer through building materials and the other is heat loss from air infiltration (gaps in doors etc). The typical New Zealand home looses half of its heat from cold air infiltration. Older houses are worse.

Many cities are particularly bad for Smog. The main cause is coal, but also damp fire wood which causes a lot of steam which mixes with the smoke causing a dense heavy smog- which does not rise into the atmosphere like smoke. People often shut their fires down (dampen) which means the wood does not burn properly, resulting in incomplete combustion. New fires do not have the same ability to shut the fire down for this reason.

Do not use coal, but dry wood. Wood burners will cause less CO to be released, resulting in complete combustion releasing CO2 –less harmful and more heat from your wood.

Inefficient combustion (incomplete) C6H12O6 (s) + 1/2 02 (g) -> C(s) + 5CO + 6 H2O  
6H12O6 is glucose, the primary fuel in wood.

What can you do to decrease your energy requirements?

Your power consumption can be broken down into to following table.   

Water Heating


Space Heating




Other Appliances









Leaks in doors and windows are the biggest heat waster. To reduce heat loss you can increase insulation by

1.       Sealing doors and windows – put rugs up against doors to stop draft

2.       Insulation (bats) in roof and under floor

3.       Closing doors and only heating rooms you use

4.       Shut the doors of rooms you do not use.

5.       Double Glaze windows

6.       Use/install curtains.

7.       If you have a fire, but aren’t using it to heat, make sure you have the damper completely closed. If it is an open fire, shut the chimney off, preferably at the bottom. A chimney is a direct opening to the outside and hot air rises.

Other minor often overlooked issues are;

8.     Ducts for cloths dryers are like leaving windows open.

9.     Power points can cause drafts


         Clothing is a renewable resource, use it!

         Heat pumps can reduce energy requirements - up to 4 times more heat output than standard filament heaters.

         A lot of heat is in the attic. Use fans and circulation systems to pump this air to where it is needed.


Other tips to reduce power;

         Install eco-bulbs if the light is suitable

         Turn appliances off at the wall, not the remote. Standby power is substantial.

         When you leave a room, turn the light off and shut the door if you don’t want it heated or the heat to get out.

         Buy energy efficient appliances. They may cost more, but this will be pay back quickly.

         Buy a cent-a-meter. This will give you the amount you are paying at that time.

         If you have an open fire, consider replacing it for a more efficient log burner.

         Make sure North Facing windows are clear from trees and obstructions. Let the suns free energy do the heating for you.

The above was all for keeping warm, what about in summer? Well similar responses are required.

         Insulation will keep the place cool

         Lighting will create heat.  Use eco-bulbs, or leave lights off.

         Use ceiling fans, but in the opposite direction as in winter.

         Shut curtains during day - especially north facing

Dry and warm homes have huge benefits for health.

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                      Please contact me for any suggestions or comments